Lunarpedia - User contributions [en]

Lunar Carbon Production

2011-10-04T23:18:02Z

205.208.203.59: /* Carbon Monoxide Reduction */

== Introduction ==
Lunar [[carbon]] is found in trace amounts in the lunar regolith, where it can be extracted by heating (see [[Volatiles]]). This process results in a number of carbon compounds, chiefly carbon monoxide ([[Carbon|C]][[Oxygen|O]]), carbon dioxide ([[Carbon|C]][[Oxygen|O]]2), and methane ([[Carbon|C]][[Hydrogen|H]]4). It is desirable to produce elemental carbon from these feedstocks for production of lunar steel, as well as various other uses. In addition, processes to reduce these substances would be necessary in order to recycle carbon consumed in various industrial processes. A number of methods have been proposed for this.

== Carbon Monoxide Reduction ==
Carbon monoxide can be subjected to temperatures of around 700°C and then quickly cooled to produce carbon and carbon dioxide, also known as the Boudouard Reaction.<ref>[http://www.moonminer.com/Basic-Chemistry-for-Moon-Miners.html Dietzler,Dave. "Basic Chemistry for Moon Miners" www.moonminer.com]</ref><ref>[http://en.wikipedia.org/wiki/Boudouard_reaction Boudouard Reaction on Wikipedia]</ref>:

2 [[Carbon Monoxide|CO]] ==> [[Carbon|C]] + [[Carbon Dioxide|CO2]]

This would recover half the carbon present in the gas. Further reduction of the carbon dioxide would be required to obtain the rest.

== Methane Reduction ==
Methane may be useful on its own as a feedstock for producing various hydrocarbons. If elemental carbon is desired, it can be subjected to thermal decomposition at high temperatures, producing [[hydrogen]] as a byproduct:
 [[Methane|CH4]] ==> [[Carbon|C]] + 2 [[Hydrogen|H]]2

Production of carbon and hydrogen in this manner has been tested with various catalysts. All had issues with carbon deposition fouling the catalyst surface. Uncatalyzed production seems to require temperatures significantly greater than 900°C <ref>Zabidi, N.A.M. and Zein, S.H.S. and Mohamed, A.R. [http://www.utp.edu.my/publications/platform/Platform%20v3n2.pdf#page=4 "Hydrogen production by catalytic decomposition of methane"] Technology Platform: Oilfield Gas Treatment and Utilization</ref>.

Uncatalyzed production has the advantage that any vessel capable of holding and heating the methane could be used as a reactor, even a simple pipe<ref>http://en.wikipedia.org/wiki/Sabatier_reaction#International_Space_Station_life_support</ref>, which could be periodically subjected to an auger to remove deposited carbon.

== Carbon Dioxide Reduction ==

=== Bosch Reaction ===

In the Bosch Reaction, carbon dioxide is reacted with hydrogen in the presence of an iron catalyst at temperatures between 530 and 730 ºC, producing carbon and water in a slightly exothermic process. The water is [[Water Splitting|split]], recovering the hydrogen and producing oxygen.

 [[Carbon Dioxide|CO2]] + 2 [[Hydrogen|H]]2 ==> [[Carbon|C]] + 2 [[Water|H2O]] (Bosch Reaction)
 2 [[Water|H2O]] ==> [[Oxygen|O]]2 + 2 [[Hydrogen|H]]2 ([[Water Splitting]])
 Net Reaction: [[Carbon Dioxide|CO2]] ==> [[Carbon|C]] + [[Oxygen|O]]2

This possesses the same disadvantage as low temperature methane decomposition, namely that the produced carbon builds up on the catalyst surface, reducing the efficiency. A combination of continuous mechanical scraping and large catalyst surfaces could make the reaction useable.

The bosch reaction is a subject of current research for space based carbon dioxide reduction<ref>http://people.oregonstate.edu/~atwaterj/h2o_gen.htm</ref>.

=== Sabatier Reaction ===
Another way to produce carbon from carbon dioxide is by use of the Sabatier reaction, which again involves reacting carbon dioxide with hydrogen, this time in the presence of a nickel catalyst. This process produces water and methane as reaction products:

 [[Carbon Dioxide|CO2]] + 4 [[Hydrogen|H]]2 ==> [[Methane|CH4]] + 2 [[Water|H2O]]

The water is split to recover hydrogen and oxygen, as in application of the Bosch reaction. The methane could be decomposed to carbon and hydrogen (see [[Lunar_Carbon_Production#Methane_Reduction|previous section]]), or used for the production of other hydrocarbons.

The Sabatier Reaction is currently utilized on board the International Space Station, except that the methane produced is dumped overboard.

=== Direct CO2 Electrolysis ===
Another option is to directly electrolyze carbon dioxide<ref>[http://rtreport.ksc.nasa.gov/techreports/2002report/600%20Fluid%20Systems/609.html "Space Habitat Carbon Dioxide Electrolysis to Oxygen". Fluid System Technologies, 2002]</ref>, resulting in oxygen and carbon monoxide.
 
2 [[Carbon Dioxide|CO2]] ==> 2 [[Carbon Monoxide|CO]] + [[Oxygen|O]]2

An appropriate membrane could be utilized to separate the oxygen. The carbon monoxide could be reduced to carbon and carbon dioxide (see [[Lunar Carbon Production#Carbon Monoxide Reduction|previous section]]), returning the carbon dioxide to the cell for further reduction.

A number of processes utilizing carbon monoxide as a reducing agent have been proposed for lunar use. These processes would consume carbon monoxide and produce carbon dioxide. A direct electrolysis system could be used in this case on the produced carbon dioxide, with the carbon monoxide recirculated back into the system rather than reduced further.

=== Biological Reduction ===
Carbon could be produced by heating organic material in the absence of oxygen to produce charcoal. This would require some method of removing the ash which would inevitably be present.

Growing plants specifically to produce carbon in this fashion would probably be more energy intensive than other methods. However, processing of organic waste products into carbon presents an attractive recycling mechanism, as it can be utilized on the non-edible parts of food plants and even human feces. This process would most likely be carried out in conjunction with other carbon production methods, as the human population would need to be quite high for it to supply all the carbon.

== References ==

<references/>

Lunar Carbon Production

2011-10-04T23:17:34Z

205.208.203.59: /* Carbon Monoxide Reduction */ added link to Boudouard Reaction on wikipedia

== Introduction ==
Lunar [[carbon]] is found in trace amounts in the lunar regolith, where it can be extracted by heating (see [[Volatiles]]). This process results in a number of carbon compounds, chiefly carbon monoxide ([[Carbon|C]][[Oxygen|O]]), carbon dioxide ([[Carbon|C]][[Oxygen|O]]2), and methane ([[Carbon|C]][[Hydrogen|H]]4). It is desirable to produce elemental carbon from these feedstocks for production of lunar steel, as well as various other uses. In addition, processes to reduce these substances would be necessary in order to recycle carbon consumed in various industrial processes. A number of methods have been proposed for this.

== Carbon Monoxide Reduction ==
Carbon monoxide can be subjected to temperatures of around 700°C and then quickly cooled to produce carbon and carbon dioxide, also known as the Boudouard Reaction.<ref>[http://www.moonminer.com/Basic-Chemistry-for-Moon-Miners.html Dietzler,Dave. "Basic Chemistry for Moon Miners" www.moonminer.com]</ref><ref>[http://en.wikipedia.org/wiki/Boudouard_reaction] Boudouard Reaction on Wikipedia</ref>:

2 [[Carbon Monoxide|CO]] ==> [[Carbon|C]] + [[Carbon Dioxide|CO2]]

This would recover half the carbon present in the gas. Further reduction of the carbon dioxide would be required to obtain the rest.

== Methane Reduction ==
Methane may be useful on its own as a feedstock for producing various hydrocarbons. If elemental carbon is desired, it can be subjected to thermal decomposition at high temperatures, producing [[hydrogen]] as a byproduct:
 [[Methane|CH4]] ==> [[Carbon|C]] + 2 [[Hydrogen|H]]2

Production of carbon and hydrogen in this manner has been tested with various catalysts. All had issues with carbon deposition fouling the catalyst surface. Uncatalyzed production seems to require temperatures significantly greater than 900°C <ref>Zabidi, N.A.M. and Zein, S.H.S. and Mohamed, A.R. [http://www.utp.edu.my/publications/platform/Platform%20v3n2.pdf#page=4 "Hydrogen production by catalytic decomposition of methane"] Technology Platform: Oilfield Gas Treatment and Utilization</ref>.

Uncatalyzed production has the advantage that any vessel capable of holding and heating the methane could be used as a reactor, even a simple pipe<ref>http://en.wikipedia.org/wiki/Sabatier_reaction#International_Space_Station_life_support</ref>, which could be periodically subjected to an auger to remove deposited carbon.

== Carbon Dioxide Reduction ==

=== Bosch Reaction ===

In the Bosch Reaction, carbon dioxide is reacted with hydrogen in the presence of an iron catalyst at temperatures between 530 and 730 ºC, producing carbon and water in a slightly exothermic process. The water is [[Water Splitting|split]], recovering the hydrogen and producing oxygen.

 [[Carbon Dioxide|CO2]] + 2 [[Hydrogen|H]]2 ==> [[Carbon|C]] + 2 [[Water|H2O]] (Bosch Reaction)
 2 [[Water|H2O]] ==> [[Oxygen|O]]2 + 2 [[Hydrogen|H]]2 ([[Water Splitting]])
 Net Reaction: [[Carbon Dioxide|CO2]] ==> [[Carbon|C]] + [[Oxygen|O]]2

This possesses the same disadvantage as low temperature methane decomposition, namely that the produced carbon builds up on the catalyst surface, reducing the efficiency. A combination of continuous mechanical scraping and large catalyst surfaces could make the reaction useable.

The bosch reaction is a subject of current research for space based carbon dioxide reduction<ref>http://people.oregonstate.edu/~atwaterj/h2o_gen.htm</ref>.

=== Sabatier Reaction ===
Another way to produce carbon from carbon dioxide is by use of the Sabatier reaction, which again involves reacting carbon dioxide with hydrogen, this time in the presence of a nickel catalyst. This process produces water and methane as reaction products:

 [[Carbon Dioxide|CO2]] + 4 [[Hydrogen|H]]2 ==> [[Methane|CH4]] + 2 [[Water|H2O]]

The water is split to recover hydrogen and oxygen, as in application of the Bosch reaction. The methane could be decomposed to carbon and hydrogen (see [[Lunar_Carbon_Production#Methane_Reduction|previous section]]), or used for the production of other hydrocarbons.

The Sabatier Reaction is currently utilized on board the International Space Station, except that the methane produced is dumped overboard.

=== Direct CO2 Electrolysis ===
Another option is to directly electrolyze carbon dioxide<ref>[http://rtreport.ksc.nasa.gov/techreports/2002report/600%20Fluid%20Systems/609.html "Space Habitat Carbon Dioxide Electrolysis to Oxygen". Fluid System Technologies, 2002]</ref>, resulting in oxygen and carbon monoxide.
 
2 [[Carbon Dioxide|CO2]] ==> 2 [[Carbon Monoxide|CO]] + [[Oxygen|O]]2

An appropriate membrane could be utilized to separate the oxygen. The carbon monoxide could be reduced to carbon and carbon dioxide (see [[Lunar Carbon Production#Carbon Monoxide Reduction|previous section]]), returning the carbon dioxide to the cell for further reduction.

A number of processes utilizing carbon monoxide as a reducing agent have been proposed for lunar use. These processes would consume carbon monoxide and produce carbon dioxide. A direct electrolysis system could be used in this case on the produced carbon dioxide, with the carbon monoxide recirculated back into the system rather than reduced further.

=== Biological Reduction ===
Carbon could be produced by heating organic material in the absence of oxygen to produce charcoal. This would require some method of removing the ash which would inevitably be present.

Growing plants specifically to produce carbon in this fashion would probably be more energy intensive than other methods. However, processing of organic waste products into carbon presents an attractive recycling mechanism, as it can be utilized on the non-edible parts of food plants and even human feces. This process would most likely be carried out in conjunction with other carbon production methods, as the human population would need to be quite high for it to supply all the carbon.

== References ==

<references/>

Sulfur

2011-09-22T19:07:17Z

205.208.203.59: Trolite is not magnetic, added changes to reflect methods of gathering

{{Element |
name=Sulfur |
symbol=S |
available=good |
need= |
number=16 |
mass=32.066 |
group=16 |
period=3 |
phase=Solid |
series=Non-metals |
density=(alpha) 2.07 g/cm3 
(beta) 1.96 g/cm3 
(gamma) 1.92 g/cm3 |
melts=388.36K, 115.21°C, 239.38°F |
boils=717.8K, 444.6°C, 832.3°F |
isotopes=32 33 34 36 |
prior=[[Phosphorus|P]] |
next=[[Chlorine|Cl]] |
above=[[Oxygen|O]] |
aprior=[[Nitrogen|N]] |
anext=[[Fluorine|F]] |
below=[[Selenium|Se]] |
bprior=[[Arsenic|As]] |
bnext=[[Bromine|Br]] |
radius=100 |
bohr=88 |
covalent=102 |
vdwr=180 |
irad=(-2) 184 |
ipot=10.36 |
econfig=1s2 2s2 2p6 3s2 3p4 |
eshell=2, 8, 6 |
enega=2.58 |
eaffin=2.08 |
oxstat=+/-2, 4, '''6''' |
magn=? |
cryst=Orthorhombic |
}}
'''Sulfur''' is a Non-metal in group 16.
It has a Orthorhombic crystalline structure.
This element has 4 stable isotopes: 32, 33, 34, and 36.
 

Sulfur is availible in lunar soil in significant quantities, principally in the form of troilite ([[Iron|Fe]]S), comprising around 1% of the lunar crust<ref name="wikisulfur">[http://en.wikipedia.org/wiki/Troilite Troilite on Wikipedia]</ref>. In addition, concentrated veins of troilite have been found in some lunar rocks, and it has been suggested that larger deposits of the mineral may exist<ref>I. Casanova. [http://www.lpi.usra.edu/meetings/lpsc97/pdf/1483.PDF Feasibility and Applications of Sulfur Concrete for Lunar Base Development: A Preliminary Study.] Lunar and Planetary Science XXVIII</ref>.

Troilite is non-magnetic when its crystal structure is complete. However, it is commonly associated with native iron in the lunar regolith. As such, [[Iron Beneficiation|magnetic gathering of iron fines]] could produce a significant amount of troilite as a byproduct. Troilite may also be separable from the lunar regolith by a combination of mechanical sifting and electrostatic beneficiation.

Several uses have been proposed for lunar sulfur, including [[In-Situ Propellant Production|rocket propellant]], production of sulfuric acid for industrial processes, lunar concrete, and sealants<ref>[http://www.nss.org/settlement/moon/library/LB2-509-UsesOfLunarSulfur.pdf V. T. Vaniman, D. R. Pettit, G. Heiken. "Uses of Lunar Sulfur" Los Alamos National Laboratory, 1988]</ref>.

== References ==
<references/>

[[Category:Solids]]
[[Category:Non-metals ]]

Sulfur

2011-09-22T18:52:06Z

205.208.203.59:

{{Element |
name=Sulfur |
symbol=S |
available=good |
need= |
number=16 |
mass=32.066 |
group=16 |
period=3 |
phase=Solid |
series=Non-metals |
density=(alpha) 2.07 g/cm3 
(beta) 1.96 g/cm3 
(gamma) 1.92 g/cm3 |
melts=388.36K, 115.21°C, 239.38°F |
boils=717.8K, 444.6°C, 832.3°F |
isotopes=32 33 34 36 |
prior=[[Phosphorus|P]] |
next=[[Chlorine|Cl]] |
above=[[Oxygen|O]] |
aprior=[[Nitrogen|N]] |
anext=[[Fluorine|F]] |
below=[[Selenium|Se]] |
bprior=[[Arsenic|As]] |
bnext=[[Bromine|Br]] |
radius=100 |
bohr=88 |
covalent=102 |
vdwr=180 |
irad=(-2) 184 |
ipot=10.36 |
econfig=1s2 2s2 2p6 3s2 3p4 |
eshell=2, 8, 6 |
enega=2.58 |
eaffin=2.08 |
oxstat=+/-2, 4, '''6''' |
magn=? |
cryst=Orthorhombic |
}}
'''Sulfur''' is a Non-metal in group 16.
It has a Orthorhombic crystalline structure.
This element has 4 stable isotopes: 32, 33, 34, and 36.
 

Sulfur is availible in lunar soil in significant quantities, principally in the form of troilite ([[Iron|Fe]]S), comprising around 1% of the lunar crust<ref name="wikisulfur">[http://en.wikipedia.org/wiki/Troilite Troilite on Wikipedia]</ref>. Magnetic benefication may be able to concentrate troilite out of the lunar regolith, as it is weakly magnetic when the crystal structure is incomplete, as well as being commonly associated with native iron<ref name="wikisulfur"> </ref>. In addition, concentrated veins of troilite have been found in some lunar rocks, and it has been suggested that larger deposits of the mineral may exist<ref>I. Casanova. [http://www.lpi.usra.edu/meetings/lpsc97/pdf/1483.PDF Feasibility and Applications of Sulfur Concrete for Lunar Base Development: A Preliminary Study.] Lunar and Planetary Science XXVIII</ref>.

Several uses have been proposed for lunar sulfur, including [[In-Situ Propellant Production|rocket propellant]], production of sulfuric acid for industrial processes, lunar concrete, and sealants<ref>[http://www.nss.org/settlement/moon/library/LB2-509-UsesOfLunarSulfur.pdf V. T. Vaniman, D. R. Pettit, G. Heiken. "Uses of Lunar Sulfur" Los Alamos National Laboratory, 1988]</ref>.

== References ==
<references/>

[[Category:Solids]]
[[Category:Non-metals ]]

Lunar Aluminum Production

2011-09-09T18:12:09Z

205.208.203.59: /* Subchloride Process */

Since Luna lacks any known deposits of bauxite, the ore most commonly used on earth for aluminum production, [[anorthite]] (CaAl2Si2O8) is most commonly proposed as a lunar substitute.<ref>http://www.permanent.com/l-minera.htm#aluminum</ref> [[Anorthite]] could be separated from the lunar highland material [[Anorthosite]] with mechanical methods. It could then be reduced through various chemical and electrochemical methods to produce [[aluminum]].

== Anorthite Production ==

The [[Anorthosite]] which makes up the Lunar highlands is a mix of [[Plagioclase]]s, [[Olivine]]s, and [[Pyroxene]]s. To separate the [[anorthite]], [[anorthosite]] must be ground. Then, magnetic separation could leave the non-magnetic anorthite.

The magnetic materials ([[Ilmenite]] and iron oxide) could be stored for production of [[titanium]], [[iron]], and [[oxygen]].

== Anorthite Refinement ==

===Direct Reduction===
Main Article: [[FFC Cambridge Process#Aluminum/Silicon/Calcium Production from Anorthite|FFC Cambridge Process]]

[[Anorthite]] could be directly reduced to its component metals using the [[FFC Cambridge Process]]. The [[Anorthite]] is pressed/sintered into a cathode, which is placed in a bath of molten calcium chloride and electrolyzed. The oxygen is stripped out, leaving behind [[Aluminum]], [[Calcium]], and [[Silicon]].

This process has the advantage of inherent simplicity, as well as having only one component to recycle, the calcium chloride, which does not react chemically with the inputs, making recovery much simpler. In addition, this process runs at lower temperatures (900º-1100º C) than many other electrolysis procedures, and inert(non-consumable) anodes have been successfully demonstrated with it<ref>http://www.lpi.usra.edu/meetings/roundtable2006/pdf/tripuraneni.pdf</ref>. On the downside, energy must be expended to split all the components of the [[Anorthite]], not just the [[aluminum]]. Splitting the silicon and calcium adds a significant amount of extra energy to the process, as both of them are strong reducers. However, if the silicon and calcium byproducts were needed for other purposes (calcium is a good [[Electrical Conductors|electrical conductor]], and silicon could be used for solar panels or [[In-Situ Propellant Production|rocket fuel]]), this extra energy cost may not be an issue.

=== Alumina Production ===

Many processes used on earth or proposed for Lunar use require [[Alumina]] ([[Aluminum|Al]]2[[Oxygen|O]]3) as an input. On Earth, alumina is produced from bauxite through the Bayer process. As this process is not feasible using Anorthite, another method must be utilized.

====Vacuum Distillation====

[[Alumina]] could be produced from Anorthite by boiling out the impurities between 1500 ºC - 2000 ºC under vacuum conditions. The resulting material would be calcium aluminate ([[Ca]][[Al]][[O]]4). Raising the temperature further could cause [[alumina]] to volatilize as well. <ref>http://www.moonminer.com/Lunar_Aluminum.html</ref>

====Sulfuric Acid Leaching====

Another method is to produce calcium aluminate as outlined previously, which is then leached in sulfuric acid, resulting in the following reaction:

[[Ca]][[Al]]2[[O]]4 + [[Sulfuric Acid |4H2SO4]] ==> [[Ca]][[S]][[O]]4 + [[Al]]2([[S]][[O]]4)3 + 4[[water |H2O]]

Aluminium sulfate in hexadecahydrate form ([[Al]]2([[S]][[O]]4)3) is then separated from calcium sulphate ([[Ca]][[S]][[O]]4 + [[Al]]2([[S]][[O]]4)3) by filtering and from water by evaporation (and then recovered).

Finally Alumina is obtained by roasting the aluminum sulfate releasing [[S]]2.<ref>http://www.moonminer.com/Lunar_Aluminum.html</ref>

====Hydrochloric Acid Leaching====
Another option is to react [[Anorthite]] with hydrochloric acid, which results in following reaction:

: [[Ca]][[Al]]2[[Si]]2[[O]]8 + 8 [[H]][[Cl]] + 2 [[H]]2[[O]]==> [[Ca]][[Cl]]2 + 2 [[Al]][[Cl]]3.6 [[H]]2[[O]] + 2 [[Si]][[O]]2

The calcium chloride and hydrated aluminum chloride dissolve in the solution and are removed. They are then precipitated out of solution, dried, and heated under partial vacuum until the calcium chloride evaporates out of the mix. Temperatures of this range will cause the hydrated aluminum chloride to become [[alumina]], releasing water and hydrogen chloride in the process:

: 2 AlCl3.6 H2O ==> Al2O3 + 6 HCl + 3 H2O

The water and hydrogen chloride are separated from the calcium chloride and fed back into the system. The calcium chloride is then electrolyzed into metallic calcium and chlorine. A portion of the recovered water is then [[Water Splitting|split]] into hydrogen and oxygen. The hydrogen component is reacted with the evolved chlorine to produce hydrogen chloride, which is then fed back into the main system.

=== Direct Calcium Aluminate / Alumina Reduction ===

Calcium Aluminate (see above for production) could be simply melted and electrolyzed directly, producing aluminum and calcium oxide.<ref>http://www.moonminer.com/Lunar_Aluminum.html</ref> This has two advantages. First, it requires no imported reagents, and second, only the aluminum is split, reducing the amount of energy needed. The disadvantage is that temperatures of approximately 1600 ºC are required, making electrode material of prime concern. Carbon electrodes could be utilized at those temperatures, but the anode would continually wear away as oxygen was produced around it, creating carbon monoxide. The carbon would need to be [[Lunar Carbon Production|recovered]] and new anodes made from it. This effectively means that a rare reagent is needed, negating the process's first stated advantage. Finding an anode material that would produce oxygen without wearing away at those temperatures could be quite difficult.

Alumina could also be directly melted and electrolyzed in the same fashion. However, this would require temperatures of approximately 2000 ºC, bringing with it again the issue of electrode material.

=== Hall-Heroult Process ===

In the Hall-Heroult process, alumina is dissolved in molten cryolite ([[Sodium]] hexafluoroaluminate, Na3 AlF6 ) around 1400 ºC. This mix is electrolyzed to separate two byproducts: aluminium and CO2. The carbon comes from the consumption of the carbon anode.

This procedure is used extensively on earth for aluminum production, and as such has the advantage of being a very mature technology. The biggest issue is the consumption of the anode, which would require the produced carbon monoxide to be captured, [[Lunar Carbon Production|converted back into carbon]], and recast into new anodes; an energy intensive process. It is not known if an inert(non-consumable) anode material can be found that would work under these conditions.<ref>http://en.wikipedia.org/wiki/Hall-H%C3%A9roult_process</ref>

=== Subchloride Process ===

In the subchloride process [[alumina]] is reacted with [[carbon]] and [[chlorine]] to yield [[Al]][[Cl]]3 and [[Carbon dioxide |CO2]]. The [[Al]][[Cl]]3 is electrolyzed to produce [[aluminum]] while recovering the [[chlorine]]. This has the advantage that conventional [[carbon]] electrodes can be used continuously, as the produced [[chlorine]] does not react with them. However, the [[Carbon dioxide |CO2]] byproduct must be [[Lunar Carbon Production|recycled]], adding extra complexity and energy requirements to the system. This makes it similar to the Hall-Heroult process in difficulty, except for two advantages. First, the recycled carbon can be directly used in powdered form, it does not need to be recast into electrodes. Second, due to the low melting point of [[Al]][[Cl]]3 (120 ºC), the process does not require significant energy to melt, and is more easily handled. <ref>http://www.moonminer.com/Lunar_Aluminum.html </ref>

=== Carbothermal Reduction ===

Carbon reduction of Alumina is impossible under normal smelting conditions, due to [[aluminum]]s high reduction potential. However, Alumina could be mixed with silica and carbon and melted near 2000 C, which would form an aluminium-silicon alloy, as well as CO2. This could be separated by cooling the Al-Si mixture to 700 - 1000 ºC and allowing the silicon to solidify and settle out of the melt.<ref>http://www.moonminer.com/Lunar_Aluminum.html </ref>

An alternate process involves alumina and carbon processed at high temperatures and low pressure into Al4C3 and carbon monoxide.<ref> [http://en.wikipedia.org/wiki/Aluminium ''Aluminum'' section ''Production and refinement''] </ref>
<ref> [http://www.moonminer.com/Lunar_Aluminum.html ''Lunar Aluminum'' at ''Moondust index''] </ref> This breaks down into Aluminum and Carbon between 1900 and 2000 ºC.<ref> [http://en.wikipedia.org/wiki/Aluminum_carbide ''Aluminium carbide'' at ''Wikipedia''] </ref>.

In either case, CO2/CO would have to be recovered and and the [[Lunar Carbon Production|carbon recycled]].

== See Also ==

*[[Aluminium]]
*[[Magma Electrolysis]]
*[[ISRU]]
*[[List of Proposed Metal Production Methods]]

== References ==
<references/>

[[Category:Industrial Production]]

Lunar Carbon Production

2011-09-08T21:12:44Z

205.208.203.59: /* Bosch Reaction */

== Introduction ==
Lunar [[carbon]] is found in trace amounts in the lunar regolith, where it can be extracted by heating (see [[Volatiles]]). This process results in a number of carbon compounds, chiefly carbon monoxide ([[Carbon|C]][[Oxygen|O]]), carbon dioxide ([[Carbon|C]][[Oxygen|O]]2), and methane ([[Carbon|C]][[Hydrogen|H]]4). It is desirable to produce elemental carbon from these feedstocks for production of lunar steel, as well as various other uses. In addition, processes to reduce these substances would be necessary in order to recycle carbon consumed in various industrial processes. A number of methods have been proposed for this.

== Carbon Monoxide Reduction ==
Carbon monoxide can be subjected to temperatures of around 700°C to produce carbon and carbon dioxide, a reaction that occurs in sooty chimneys.<ref>[http://www.moonminer.com/Basic-Chemistry-for-Moon-Miners.html Dietzler,Dave. "Basic Chemistry for Moon Miners" www.moonminer.com]</ref>:

2 [[Carbon Monoxide|CO]] ==> [[Carbon|C]] + [[Carbon Dioxide|CO2]]

This would recover half the carbon present in the gas. Further reduction of the carbon dioxide would be required to obtain the rest.

== Methane Reduction ==
Methane may be useful on its own as a feedstock for producing various hydrocarbons. If elemental carbon is desired, it can be subjected to thermal decomposition at high temperatures, producing [[hydrogen]] as a byproduct:
 [[Methane|CH4]] ==> [[Carbon|C]] + 2 [[Hydrogen|H]]2

Production of carbon and hydrogen in this manner has been tested with various catalysts. All had issues with carbon deposition fouling the catalyst surface. Uncatalyzed production seems to require temperatures significantly greater than 900°C <ref>Zabidi, N.A.M. and Zein, S.H.S. and Mohamed, A.R. [http://www.utp.edu.my/publications/platform/Platform%20v3n2.pdf#page=4 "Hydrogen production by catalytic decomposition of methane"] Technology Platform: Oilfield Gas Treatment and Utilization</ref>.

Uncatalyzed production has the advantage that any vessel capable of holding and heating the methane could be used as a reactor, even a simple pipe<ref>http://en.wikipedia.org/wiki/Sabatier_reaction#International_Space_Station_life_support</ref>, which could be periodically subjected to an auger to remove deposited carbon.

== Carbon Dioxide Reduction ==

=== Bosch Reaction ===

In the Bosch Reaction, carbon dioxide is reacted with hydrogen in the presence of an iron catalyst at temperatures between 530 and 730 ºC, producing carbon and water in a slightly exothermic process. The water is [[Water Splitting|split]], recovering the hydrogen and producing oxygen.

 [[Carbon Dioxide|CO2]] + 2 [[Hydrogen|H]]2 ==> [[Carbon|C]] + 2 [[Water|H2O]] (Bosch Reaction)
 2 [[Water|H2O]] ==> [[Oxygen|O]]2 + 2 [[Hydrogen|H]]2 ([[Water Splitting]])
 Net Reaction: [[Carbon Dioxide|CO2]] ==> [[Carbon|C]] + [[Oxygen|O]]2

This possesses the same disadvantage as low temperature methane decomposition, namely that the produced carbon builds up on the catalyst surface, reducing the efficiency. A combination of continuous mechanical scraping and large catalyst surfaces could make the reaction useable.

The bosch reaction is a subject of current research for space based carbon dioxide reduction<ref>http://people.oregonstate.edu/~atwaterj/h2o_gen.htm</ref>.

=== Sabatier Reaction ===
Another way to produce carbon from carbon dioxide is by use of the Sabatier reaction, which again involves reacting carbon dioxide with hydrogen, this time in the presence of a nickel catalyst. This process produces water and methane as reaction products:

 [[Carbon Dioxide|CO2]] + 4 [[Hydrogen|H]]2 ==> [[Methane|CH4]] + 2 [[Water|H2O]]

The water is split to recover hydrogen and oxygen, as in application of the Bosch reaction. The methane could be decomposed to carbon and hydrogen (see [[Lunar_Carbon_Production#Methane_Reduction|previous section]]), or used for the production of other hydrocarbons.

The Sabatier Reaction is currently utilized on board the International Space Station, except that the methane produced is dumped overboard.

=== Direct CO2 Electrolysis ===
Another option is to directly electrolyze carbon dioxide<ref>[http://rtreport.ksc.nasa.gov/techreports/2002report/600%20Fluid%20Systems/609.html "Space Habitat Carbon Dioxide Electrolysis to Oxygen". Fluid System Technologies, 2002]</ref>, resulting in oxygen and carbon monoxide.
 
2 [[Carbon Dioxide|CO2]] ==> 2 [[Carbon Monoxide|CO]] + [[Oxygen|O]]2

An appropriate membrane could be utilized to separate the oxygen. The carbon monoxide could be reduced to carbon and carbon dioxide (see [[Lunar Carbon Production#Carbon Monoxide Reduction|previous section]]), returning the carbon dioxide to the cell for further reduction.

A number of processes utilizing carbon monoxide as a reducing agent have been proposed for lunar use. These processes would consume carbon monoxide and produce carbon dioxide. A direct electrolysis system could be used in this case on the produced carbon dioxide, with the carbon monoxide recirculated back into the system rather than reduced further.

=== Biological Reduction ===
Carbon could be produced by heating organic material in the absence of oxygen to produce charcoal. This would require some method of removing the ash which would inevitably be present.

Growing plants specifically to produce carbon in this fashion would probably be more energy intensive than other methods. However, processing of organic waste products into carbon presents an attractive recycling mechanism, as it can be utilized on the non-edible parts of food plants and even human feces. This process would most likely be carried out in conjunction with other carbon production methods, as the human population would need to be quite high for it to supply all the carbon.

== References ==

<references/>

Lunar Aluminum Production

2011-09-08T21:10:16Z

205.208.203.59: /* Carbothermal Reduction */

Since Luna lacks any known deposits of bauxite, the ore most commonly used on earth for aluminum production, [[anorthite]] (CaAl2Si2O8) is most commonly proposed as a lunar substitute.<ref>http://www.permanent.com/l-minera.htm#aluminum</ref> [[Anorthite]] could be separated from the lunar highland material [[Anorthosite]] with mechanical methods. It could then be reduced through various chemical and electrochemical methods to produce [[aluminum]].

== Anorthite Production ==

The [[Anorthosite]] which makes up the Lunar highlands is a mix of [[Plagioclase]]s, [[Olivine]]s, and [[Pyroxene]]s. To separate the [[anorthite]], [[anorthosite]] must be ground. Then, magnetic separation could leave the non-magnetic anorthite.

The magnetic materials ([[Ilmenite]] and iron oxide) could be stored for production of [[titanium]], [[iron]], and [[oxygen]].

== Anorthite Refinement ==

===Direct Reduction===
Main Article: [[FFC Cambridge Process#Aluminum/Silicon/Calcium Production from Anorthite|FFC Cambridge Process]]

[[Anorthite]] could be directly reduced to its component metals using the [[FFC Cambridge Process]]. The [[Anorthite]] is pressed/sintered into a cathode, which is placed in a bath of molten calcium chloride and electrolyzed. The oxygen is stripped out, leaving behind [[Aluminum]], [[Calcium]], and [[Silicon]].

This process has the advantage of inherent simplicity, as well as having only one component to recycle, the calcium chloride, which does not react chemically with the inputs, making recovery much simpler. In addition, this process runs at lower temperatures (900º-1100º C) than many other electrolysis procedures, and inert(non-consumable) anodes have been successfully demonstrated with it<ref>http://www.lpi.usra.edu/meetings/roundtable2006/pdf/tripuraneni.pdf</ref>. On the downside, energy must be expended to split all the components of the [[Anorthite]], not just the [[aluminum]]. Splitting the silicon and calcium adds a significant amount of extra energy to the process, as both of them are strong reducers. However, if the silicon and calcium byproducts were needed for other purposes (calcium is a good [[Electrical Conductors|electrical conductor]], and silicon could be used for solar panels or [[In-Situ Propellant Production|rocket fuel]]), this extra energy cost may not be an issue.

=== Alumina Production ===

Many processes used on earth or proposed for Lunar use require [[Alumina]] ([[Aluminum|Al]]2[[Oxygen|O]]3) as an input. On Earth, alumina is produced from bauxite through the Bayer process. As this process is not feasible using Anorthite, another method must be utilized.

====Vacuum Distillation====

[[Alumina]] could be produced from Anorthite by boiling out the impurities between 1500 ºC - 2000 ºC under vacuum conditions. The resulting material would be calcium aluminate ([[Ca]][[Al]][[O]]4). Raising the temperature further could cause [[alumina]] to volatilize as well. <ref>http://www.moonminer.com/Lunar_Aluminum.html</ref>

====Sulfuric Acid Leaching====

Another method is to produce calcium aluminate as outlined previously, which is then leached in sulfuric acid, resulting in the following reaction:

[[Ca]][[Al]]2[[O]]4 + [[Sulfuric Acid |4H2SO4]] ==> [[Ca]][[S]][[O]]4 + [[Al]]2([[S]][[O]]4)3 + 4[[water |H2O]]

Aluminium sulfate in hexadecahydrate form ([[Al]]2([[S]][[O]]4)3) is then separated from calcium sulphate ([[Ca]][[S]][[O]]4 + [[Al]]2([[S]][[O]]4)3) by filtering and from water by evaporation (and then recovered).

Finally Alumina is obtained by roasting the aluminum sulfate releasing [[S]]2.<ref>http://www.moonminer.com/Lunar_Aluminum.html</ref>

====Hydrochloric Acid Leaching====
Another option is to react [[Anorthite]] with hydrochloric acid, which results in following reaction:

: [[Ca]][[Al]]2[[Si]]2[[O]]8 + 8 [[H]][[Cl]] + 2 [[H]]2[[O]]==> [[Ca]][[Cl]]2 + 2 [[Al]][[Cl]]3.6 [[H]]2[[O]] + 2 [[Si]][[O]]2

The calcium chloride and hydrated aluminum chloride dissolve in the solution and are removed. They are then precipitated out of solution, dried, and heated under partial vacuum until the calcium chloride evaporates out of the mix. Temperatures of this range will cause the hydrated aluminum chloride to become [[alumina]], releasing water and hydrogen chloride in the process:

: 2 AlCl3.6 H2O ==> Al2O3 + 6 HCl + 3 H2O

The water and hydrogen chloride are separated from the calcium chloride and fed back into the system. The calcium chloride is then electrolyzed into metallic calcium and chlorine. A portion of the recovered water is then [[Water Splitting|split]] into hydrogen and oxygen. The hydrogen component is reacted with the evolved chlorine to produce hydrogen chloride, which is then fed back into the main system.

=== Direct Calcium Aluminate / Alumina Reduction ===

Calcium Aluminate (see above for production) could be simply melted and electrolyzed directly, producing aluminum and calcium oxide.<ref>http://www.moonminer.com/Lunar_Aluminum.html</ref> This has two advantages. First, it requires no imported reagents, and second, only the aluminum is split, reducing the amount of energy needed. The disadvantage is that temperatures of approximately 1600 ºC are required, making electrode material of prime concern. Carbon electrodes could be utilized at those temperatures, but the anode would continually wear away as oxygen was produced around it, creating carbon monoxide. The carbon would need to be [[Lunar Carbon Production|recovered]] and new anodes made from it. This effectively means that a rare reagent is needed, negating the process's first stated advantage. Finding an anode material that would produce oxygen without wearing away at those temperatures could be quite difficult.

Alumina could also be directly melted and electrolyzed in the same fashion. However, this would require temperatures of approximately 2000 ºC, bringing with it again the issue of electrode material.

=== Hall-Heroult Process ===

In the Hall-Heroult process, alumina is dissolved in molten cryolite ([[Sodium]] hexafluoroaluminate, Na3 AlF6 ) around 1400 ºC. This mix is electrolyzed to separate two byproducts: aluminium and CO2. The carbon comes from the consumption of the carbon anode.

This procedure is used extensively on earth for aluminum production, and as such has the advantage of being a very mature technology. The biggest issue is the consumption of the anode, which would require the produced carbon monoxide to be captured, [[Lunar Carbon Production|converted back into carbon]], and recast into new anodes; an energy intensive process. It is not known if an inert(non-consumable) anode material can be found that would work under these conditions.<ref>http://en.wikipedia.org/wiki/Hall-H%C3%A9roult_process</ref>

=== Subchloride Process ===

In the subchloride process [[alumina]] is reacted with [[carbon]] and [[chlorine]] to yield [[Al]][[Cl]]3 and [[Carbon dioxide |CO2]]. The [[Al]][[Cl]]3 is electrolyzed to produce [[Aluminum]] while recovering the [[chlorine]]. This has the advantage that conventional [[carbon]] electrodes can be used continuously, as the produced [[chlorine]] does not react with them. However, the [[Carbon dioxide |CO2]] byproduct must be [[Lunar Carbon Production|recycled]], adding extra complexity and energy requirements to the system. This makes it similar to the Hall-Heroult process in difficulty, except for two advantages. First, the recycled carbon can be directly used in powdered form, it does not need to be recast into electrodes. Second, due to the low melting point of [[Al]][[Cl]]3 (120 ºC), the process does not require significant energy to melt, and is more easily handled. <ref>http://www.moonminer.com/Lunar_Aluminum.html </ref>

=== Carbothermal Reduction ===

Carbon reduction of Alumina is impossible under normal smelting conditions, due to [[aluminum]]s high reduction potential. However, Alumina could be mixed with silica and carbon and melted near 2000 C, which would form an aluminium-silicon alloy, as well as CO2. This could be separated by cooling the Al-Si mixture to 700 - 1000 ºC and allowing the silicon to solidify and settle out of the melt.<ref>http://www.moonminer.com/Lunar_Aluminum.html </ref>

An alternate process involves alumina and carbon processed at high temperatures and low pressure into Al4C3 and carbon monoxide.<ref> [http://en.wikipedia.org/wiki/Aluminium ''Aluminum'' section ''Production and refinement''] </ref>
<ref> [http://www.moonminer.com/Lunar_Aluminum.html ''Lunar Aluminum'' at ''Moondust index''] </ref> This breaks down into Aluminum and Carbon between 1900 and 2000 ºC.<ref> [http://en.wikipedia.org/wiki/Aluminum_carbide ''Aluminium carbide'' at ''Wikipedia''] </ref>.

In either case, CO2/CO would have to be recovered and and the [[Lunar Carbon Production|carbon recycled]].

== See Also ==

*[[Aluminium]]
*[[Magma Electrolysis]]
*[[ISRU]]
*[[List of Proposed Metal Production Methods]]

== References ==
<references/>

[[Category:Industrial Production]]

Lunar Aluminum Production

2011-09-08T21:08:40Z

205.208.203.59: /* Subchloride Process */

Since Luna lacks any known deposits of bauxite, the ore most commonly used on earth for aluminum production, [[anorthite]] (CaAl2Si2O8) is most commonly proposed as a lunar substitute.<ref>http://www.permanent.com/l-minera.htm#aluminum</ref> [[Anorthite]] could be separated from the lunar highland material [[Anorthosite]] with mechanical methods. It could then be reduced through various chemical and electrochemical methods to produce [[aluminum]].

== Anorthite Production ==

The [[Anorthosite]] which makes up the Lunar highlands is a mix of [[Plagioclase]]s, [[Olivine]]s, and [[Pyroxene]]s. To separate the [[anorthite]], [[anorthosite]] must be ground. Then, magnetic separation could leave the non-magnetic anorthite.

The magnetic materials ([[Ilmenite]] and iron oxide) could be stored for production of [[titanium]], [[iron]], and [[oxygen]].

== Anorthite Refinement ==

===Direct Reduction===
Main Article: [[FFC Cambridge Process#Aluminum/Silicon/Calcium Production from Anorthite|FFC Cambridge Process]]

[[Anorthite]] could be directly reduced to its component metals using the [[FFC Cambridge Process]]. The [[Anorthite]] is pressed/sintered into a cathode, which is placed in a bath of molten calcium chloride and electrolyzed. The oxygen is stripped out, leaving behind [[Aluminum]], [[Calcium]], and [[Silicon]].

This process has the advantage of inherent simplicity, as well as having only one component to recycle, the calcium chloride, which does not react chemically with the inputs, making recovery much simpler. In addition, this process runs at lower temperatures (900º-1100º C) than many other electrolysis procedures, and inert(non-consumable) anodes have been successfully demonstrated with it<ref>http://www.lpi.usra.edu/meetings/roundtable2006/pdf/tripuraneni.pdf</ref>. On the downside, energy must be expended to split all the components of the [[Anorthite]], not just the [[aluminum]]. Splitting the silicon and calcium adds a significant amount of extra energy to the process, as both of them are strong reducers. However, if the silicon and calcium byproducts were needed for other purposes (calcium is a good [[Electrical Conductors|electrical conductor]], and silicon could be used for solar panels or [[In-Situ Propellant Production|rocket fuel]]), this extra energy cost may not be an issue.

=== Alumina Production ===

Many processes used on earth or proposed for Lunar use require [[Alumina]] ([[Aluminum|Al]]2[[Oxygen|O]]3) as an input. On Earth, alumina is produced from bauxite through the Bayer process. As this process is not feasible using Anorthite, another method must be utilized.

====Vacuum Distillation====

[[Alumina]] could be produced from Anorthite by boiling out the impurities between 1500 ºC - 2000 ºC under vacuum conditions. The resulting material would be calcium aluminate ([[Ca]][[Al]][[O]]4). Raising the temperature further could cause [[alumina]] to volatilize as well. <ref>http://www.moonminer.com/Lunar_Aluminum.html</ref>

====Sulfuric Acid Leaching====

Another method is to produce calcium aluminate as outlined previously, which is then leached in sulfuric acid, resulting in the following reaction:

[[Ca]][[Al]]2[[O]]4 + [[Sulfuric Acid |4H2SO4]] ==> [[Ca]][[S]][[O]]4 + [[Al]]2([[S]][[O]]4)3 + 4[[water |H2O]]

Aluminium sulfate in hexadecahydrate form ([[Al]]2([[S]][[O]]4)3) is then separated from calcium sulphate ([[Ca]][[S]][[O]]4 + [[Al]]2([[S]][[O]]4)3) by filtering and from water by evaporation (and then recovered).

Finally Alumina is obtained by roasting the aluminum sulfate releasing [[S]]2.<ref>http://www.moonminer.com/Lunar_Aluminum.html</ref>

====Hydrochloric Acid Leaching====
Another option is to react [[Anorthite]] with hydrochloric acid, which results in following reaction:

: [[Ca]][[Al]]2[[Si]]2[[O]]8 + 8 [[H]][[Cl]] + 2 [[H]]2[[O]]==> [[Ca]][[Cl]]2 + 2 [[Al]][[Cl]]3.6 [[H]]2[[O]] + 2 [[Si]][[O]]2

The calcium chloride and hydrated aluminum chloride dissolve in the solution and are removed. They are then precipitated out of solution, dried, and heated under partial vacuum until the calcium chloride evaporates out of the mix. Temperatures of this range will cause the hydrated aluminum chloride to become [[alumina]], releasing water and hydrogen chloride in the process:

: 2 AlCl3.6 H2O ==> Al2O3 + 6 HCl + 3 H2O

The water and hydrogen chloride are separated from the calcium chloride and fed back into the system. The calcium chloride is then electrolyzed into metallic calcium and chlorine. A portion of the recovered water is then [[Water Splitting|split]] into hydrogen and oxygen. The hydrogen component is reacted with the evolved chlorine to produce hydrogen chloride, which is then fed back into the main system.

=== Direct Calcium Aluminate / Alumina Reduction ===

Calcium Aluminate (see above for production) could be simply melted and electrolyzed directly, producing aluminum and calcium oxide.<ref>http://www.moonminer.com/Lunar_Aluminum.html</ref> This has two advantages. First, it requires no imported reagents, and second, only the aluminum is split, reducing the amount of energy needed. The disadvantage is that temperatures of approximately 1600 ºC are required, making electrode material of prime concern. Carbon electrodes could be utilized at those temperatures, but the anode would continually wear away as oxygen was produced around it, creating carbon monoxide. The carbon would need to be [[Lunar Carbon Production|recovered]] and new anodes made from it. This effectively means that a rare reagent is needed, negating the process's first stated advantage. Finding an anode material that would produce oxygen without wearing away at those temperatures could be quite difficult.

Alumina could also be directly melted and electrolyzed in the same fashion. However, this would require temperatures of approximately 2000 ºC, bringing with it again the issue of electrode material.

=== Hall-Heroult Process ===

In the Hall-Heroult process, alumina is dissolved in molten cryolite ([[Sodium]] hexafluoroaluminate, Na3 AlF6 ) around 1400 ºC. This mix is electrolyzed to separate two byproducts: aluminium and CO2. The carbon comes from the consumption of the carbon anode.

This procedure is used extensively on earth for aluminum production, and as such has the advantage of being a very mature technology. The biggest issue is the consumption of the anode, which would require the produced carbon monoxide to be captured, [[Lunar Carbon Production|converted back into carbon]], and recast into new anodes; an energy intensive process. It is not known if an inert(non-consumable) anode material can be found that would work under these conditions.<ref>http://en.wikipedia.org/wiki/Hall-H%C3%A9roult_process</ref>

=== Subchloride Process ===

In the subchloride process [[alumina]] is reacted with [[carbon]] and [[chlorine]] to yield [[Al]][[Cl]]3 and [[Carbon dioxide |CO2]]. The [[Al]][[Cl]]3 is electrolyzed to produce [[Aluminum]] while recovering the [[chlorine]]. This has the advantage that conventional [[carbon]] electrodes can be used continuously, as the produced [[chlorine]] does not react with them. However, the [[Carbon dioxide |CO2]] byproduct must be [[Lunar Carbon Production|recycled]], adding extra complexity and energy requirements to the system. This makes it similar to the Hall-Heroult process in difficulty, except for two advantages. First, the recycled carbon can be directly used in powdered form, it does not need to be recast into electrodes. Second, due to the low melting point of [[Al]][[Cl]]3 (120 ºC), the process does not require significant energy to melt, and is more easily handled. <ref>http://www.moonminer.com/Lunar_Aluminum.html </ref>

=== Carbothermal Reduction ===

Carbon reduction of Alumina is impossible under normal smelting conditions, due to [[aluminum]]s high reduction potential. However, Alumina could be mixed with silica and carbon and melted near 2000 C, which would form an aluminium-silicon alloy, as well as CO2. This could be separated by cooling the Al-Si mixture to 700 -1000 C and allowing the silicon to solidify and settle out of the melt.<ref>http://www.moonminer.com/Lunar_Aluminum.html </ref>

An alternate process involves alumina and carbon processed at high temperatures and low pressure into Al4C3 and carbon monoxide.<ref> [http://en.wikipedia.org/wiki/Aluminium ''Aluminum'' section ''Production and refinement''] </ref>
<ref> [http://www.moonminer.com/Lunar_Aluminum.html ''Lunar Aluminum'' at ''Moondust index''] </ref> This breaks down into Aluminum and Carbon between 1900 and 2000 C.<ref> [http://en.wikipedia.org/wiki/Aluminum_carbide ''Aluminium carbide'' at ''Wikipedia''] </ref>.

In either case, CO2/CO would have to be recovered and and the [[Lunar Carbon Production|carbon recycled]].

== See Also ==

*[[Aluminium]]
*[[Magma Electrolysis]]
*[[ISRU]]
*[[List of Proposed Metal Production Methods]]

== References ==
<references/>

[[Category:Industrial Production]]

Lunar Aluminum Production

2011-09-08T21:08:16Z

205.208.203.59: /* Direct Calcium Aluminate / Alumina Reduction */

Since Luna lacks any known deposits of bauxite, the ore most commonly used on earth for aluminum production, [[anorthite]] (CaAl2Si2O8) is most commonly proposed as a lunar substitute.<ref>http://www.permanent.com/l-minera.htm#aluminum</ref> [[Anorthite]] could be separated from the lunar highland material [[Anorthosite]] with mechanical methods. It could then be reduced through various chemical and electrochemical methods to produce [[aluminum]].

== Anorthite Production ==

The [[Anorthosite]] which makes up the Lunar highlands is a mix of [[Plagioclase]]s, [[Olivine]]s, and [[Pyroxene]]s. To separate the [[anorthite]], [[anorthosite]] must be ground. Then, magnetic separation could leave the non-magnetic anorthite.

The magnetic materials ([[Ilmenite]] and iron oxide) could be stored for production of [[titanium]], [[iron]], and [[oxygen]].

== Anorthite Refinement ==

===Direct Reduction===
Main Article: [[FFC Cambridge Process#Aluminum/Silicon/Calcium Production from Anorthite|FFC Cambridge Process]]

[[Anorthite]] could be directly reduced to its component metals using the [[FFC Cambridge Process]]. The [[Anorthite]] is pressed/sintered into a cathode, which is placed in a bath of molten calcium chloride and electrolyzed. The oxygen is stripped out, leaving behind [[Aluminum]], [[Calcium]], and [[Silicon]].

This process has the advantage of inherent simplicity, as well as having only one component to recycle, the calcium chloride, which does not react chemically with the inputs, making recovery much simpler. In addition, this process runs at lower temperatures (900º-1100º C) than many other electrolysis procedures, and inert(non-consumable) anodes have been successfully demonstrated with it<ref>http://www.lpi.usra.edu/meetings/roundtable2006/pdf/tripuraneni.pdf</ref>. On the downside, energy must be expended to split all the components of the [[Anorthite]], not just the [[aluminum]]. Splitting the silicon and calcium adds a significant amount of extra energy to the process, as both of them are strong reducers. However, if the silicon and calcium byproducts were needed for other purposes (calcium is a good [[Electrical Conductors|electrical conductor]], and silicon could be used for solar panels or [[In-Situ Propellant Production|rocket fuel]]), this extra energy cost may not be an issue.

=== Alumina Production ===

Many processes used on earth or proposed for Lunar use require [[Alumina]] ([[Aluminum|Al]]2[[Oxygen|O]]3) as an input. On Earth, alumina is produced from bauxite through the Bayer process. As this process is not feasible using Anorthite, another method must be utilized.

====Vacuum Distillation====

[[Alumina]] could be produced from Anorthite by boiling out the impurities between 1500 ºC - 2000 ºC under vacuum conditions. The resulting material would be calcium aluminate ([[Ca]][[Al]][[O]]4). Raising the temperature further could cause [[alumina]] to volatilize as well. <ref>http://www.moonminer.com/Lunar_Aluminum.html</ref>

====Sulfuric Acid Leaching====

Another method is to produce calcium aluminate as outlined previously, which is then leached in sulfuric acid, resulting in the following reaction:

[[Ca]][[Al]]2[[O]]4 + [[Sulfuric Acid |4H2SO4]] ==> [[Ca]][[S]][[O]]4 + [[Al]]2([[S]][[O]]4)3 + 4[[water |H2O]]

Aluminium sulfate in hexadecahydrate form ([[Al]]2([[S]][[O]]4)3) is then separated from calcium sulphate ([[Ca]][[S]][[O]]4 + [[Al]]2([[S]][[O]]4)3) by filtering and from water by evaporation (and then recovered).

Finally Alumina is obtained by roasting the aluminum sulfate releasing [[S]]2.<ref>http://www.moonminer.com/Lunar_Aluminum.html</ref>

====Hydrochloric Acid Leaching====
Another option is to react [[Anorthite]] with hydrochloric acid, which results in following reaction:

: [[Ca]][[Al]]2[[Si]]2[[O]]8 + 8 [[H]][[Cl]] + 2 [[H]]2[[O]]==> [[Ca]][[Cl]]2 + 2 [[Al]][[Cl]]3.6 [[H]]2[[O]] + 2 [[Si]][[O]]2

The calcium chloride and hydrated aluminum chloride dissolve in the solution and are removed. They are then precipitated out of solution, dried, and heated under partial vacuum until the calcium chloride evaporates out of the mix. Temperatures of this range will cause the hydrated aluminum chloride to become [[alumina]], releasing water and hydrogen chloride in the process:

: 2 AlCl3.6 H2O ==> Al2O3 + 6 HCl + 3 H2O

The water and hydrogen chloride are separated from the calcium chloride and fed back into the system. The calcium chloride is then electrolyzed into metallic calcium and chlorine. A portion of the recovered water is then [[Water Splitting|split]] into hydrogen and oxygen. The hydrogen component is reacted with the evolved chlorine to produce hydrogen chloride, which is then fed back into the main system.

=== Direct Calcium Aluminate / Alumina Reduction ===

Calcium Aluminate (see above for production) could be simply melted and electrolyzed directly, producing aluminum and calcium oxide.<ref>http://www.moonminer.com/Lunar_Aluminum.html</ref> This has two advantages. First, it requires no imported reagents, and second, only the aluminum is split, reducing the amount of energy needed. The disadvantage is that temperatures of approximately 1600 ºC are required, making electrode material of prime concern. Carbon electrodes could be utilized at those temperatures, but the anode would continually wear away as oxygen was produced around it, creating carbon monoxide. The carbon would need to be [[Lunar Carbon Production|recovered]] and new anodes made from it. This effectively means that a rare reagent is needed, negating the process's first stated advantage. Finding an anode material that would produce oxygen without wearing away at those temperatures could be quite difficult.

Alumina could also be directly melted and electrolyzed in the same fashion. However, this would require temperatures of approximately 2000 ºC, bringing with it again the issue of electrode material.

=== Hall-Heroult Process ===

In the Hall-Heroult process, alumina is dissolved in molten cryolite ([[Sodium]] hexafluoroaluminate, Na3 AlF6 ) around 1400 ºC. This mix is electrolyzed to separate two byproducts: aluminium and CO2. The carbon comes from the consumption of the carbon anode.

This procedure is used extensively on earth for aluminum production, and as such has the advantage of being a very mature technology. The biggest issue is the consumption of the anode, which would require the produced carbon monoxide to be captured, [[Lunar Carbon Production|converted back into carbon]], and recast into new anodes; an energy intensive process. It is not known if an inert(non-consumable) anode material can be found that would work under these conditions.<ref>http://en.wikipedia.org/wiki/Hall-H%C3%A9roult_process</ref>

=== Subchloride Process ===

In the subchloride process [[alumina]] is reacted with [[carbon]] and [[chlorine]] to yield [[Al]][[Cl]]3 and [[Carbon dioxide |CO2]]. The [[Al]][[Cl]]3 is electrolyzed to produce [[Aluminum]] while recovering the [[chlorine]]. This has the advantage that conventional [[carbon]] electrodes can be used continuously, as the produced [[chlorine]] does not react with them. However, the [[Carbon dioxide |CO2]] byproduct must be [[Lunar Carbon Production|recycled]], adding extra complexity and energy requirements to the system. This makes it similar to the Hall-Heroult process in difficulty, except for two advantages. First, the recycled carbon can be directly used in powdered form, it does not need to be recast into electrodes. Second, due to the low melting point of [[Al]][[Cl]]3 (120 C), the process does not require significant energy to melt, and is more easily handled. <ref>http://www.moonminer.com/Lunar_Aluminum.html </ref>

=== Carbothermal Reduction ===

Carbon reduction of Alumina is impossible under normal smelting conditions, due to [[aluminum]]s high reduction potential. However, Alumina could be mixed with silica and carbon and melted near 2000 C, which would form an aluminium-silicon alloy, as well as CO2. This could be separated by cooling the Al-Si mixture to 700 -1000 C and allowing the silicon to solidify and settle out of the melt.<ref>http://www.moonminer.com/Lunar_Aluminum.html </ref>

An alternate process involves alumina and carbon processed at high temperatures and low pressure into Al4C3 and carbon monoxide.<ref> [http://en.wikipedia.org/wiki/Aluminium ''Aluminum'' section ''Production and refinement''] </ref>
<ref> [http://www.moonminer.com/Lunar_Aluminum.html ''Lunar Aluminum'' at ''Moondust index''] </ref> This breaks down into Aluminum and Carbon between 1900 and 2000 C.<ref> [http://en.wikipedia.org/wiki/Aluminum_carbide ''Aluminium carbide'' at ''Wikipedia''] </ref>.

In either case, CO2/CO would have to be recovered and and the [[Lunar Carbon Production|carbon recycled]].

== See Also ==

*[[Aluminium]]
*[[Magma Electrolysis]]
*[[ISRU]]
*[[List of Proposed Metal Production Methods]]

== References ==
<references/>

[[Category:Industrial Production]]

Lunar Aluminum Production

2011-09-08T21:05:07Z

205.208.203.59: /* Direct Reduction */

Since Luna lacks any known deposits of bauxite, the ore most commonly used on earth for aluminum production, [[anorthite]] (CaAl2Si2O8) is most commonly proposed as a lunar substitute.<ref>http://www.permanent.com/l-minera.htm#aluminum</ref> [[Anorthite]] could be separated from the lunar highland material [[Anorthosite]] with mechanical methods. It could then be reduced through various chemical and electrochemical methods to produce [[aluminum]].

== Anorthite Production ==

The [[Anorthosite]] which makes up the Lunar highlands is a mix of [[Plagioclase]]s, [[Olivine]]s, and [[Pyroxene]]s. To separate the [[anorthite]], [[anorthosite]] must be ground. Then, magnetic separation could leave the non-magnetic anorthite.

The magnetic materials ([[Ilmenite]] and iron oxide) could be stored for production of [[titanium]], [[iron]], and [[oxygen]].

== Anorthite Refinement ==

===Direct Reduction===
Main Article: [[FFC Cambridge Process#Aluminum/Silicon/Calcium Production from Anorthite|FFC Cambridge Process]]

[[Anorthite]] could be directly reduced to its component metals using the [[FFC Cambridge Process]]. The [[Anorthite]] is pressed/sintered into a cathode, which is placed in a bath of molten calcium chloride and electrolyzed. The oxygen is stripped out, leaving behind [[Aluminum]], [[Calcium]], and [[Silicon]].

This process has the advantage of inherent simplicity, as well as having only one component to recycle, the calcium chloride, which does not react chemically with the inputs, making recovery much simpler. In addition, this process runs at lower temperatures (900º-1100º C) than many other electrolysis procedures, and inert(non-consumable) anodes have been successfully demonstrated with it<ref>http://www.lpi.usra.edu/meetings/roundtable2006/pdf/tripuraneni.pdf</ref>. On the downside, energy must be expended to split all the components of the [[Anorthite]], not just the [[aluminum]]. Splitting the silicon and calcium adds a significant amount of extra energy to the process, as both of them are strong reducers. However, if the silicon and calcium byproducts were needed for other purposes (calcium is a good [[Electrical Conductors|electrical conductor]], and silicon could be used for solar panels or [[In-Situ Propellant Production|rocket fuel]]), this extra energy cost may not be an issue.

=== Alumina Production ===

Many processes used on earth or proposed for Lunar use require [[Alumina]] ([[Aluminum|Al]]2[[Oxygen|O]]3) as an input. On Earth, alumina is produced from bauxite through the Bayer process. As this process is not feasible using Anorthite, another method must be utilized.

====Vacuum Distillation====

[[Alumina]] could be produced from Anorthite by boiling out the impurities between 1500 ºC - 2000 ºC under vacuum conditions. The resulting material would be calcium aluminate ([[Ca]][[Al]][[O]]4). Raising the temperature further could cause [[alumina]] to volatilize as well. <ref>http://www.moonminer.com/Lunar_Aluminum.html</ref>

====Sulfuric Acid Leaching====

Another method is to produce calcium aluminate as outlined previously, which is then leached in sulfuric acid, resulting in the following reaction:

[[Ca]][[Al]]2[[O]]4 + [[Sulfuric Acid |4H2SO4]] ==> [[Ca]][[S]][[O]]4 + [[Al]]2([[S]][[O]]4)3 + 4[[water |H2O]]

Aluminium sulfate in hexadecahydrate form ([[Al]]2([[S]][[O]]4)3) is then separated from calcium sulphate ([[Ca]][[S]][[O]]4 + [[Al]]2([[S]][[O]]4)3) by filtering and from water by evaporation (and then recovered).

Finally Alumina is obtained by roasting the aluminum sulfate releasing [[S]]2.<ref>http://www.moonminer.com/Lunar_Aluminum.html</ref>

====Hydrochloric Acid Leaching====
Another option is to react [[Anorthite]] with hydrochloric acid, which results in following reaction:

: [[Ca]][[Al]]2[[Si]]2[[O]]8 + 8 [[H]][[Cl]] + 2 [[H]]2[[O]]==> [[Ca]][[Cl]]2 + 2 [[Al]][[Cl]]3.6 [[H]]2[[O]] + 2 [[Si]][[O]]2

The calcium chloride and hydrated aluminum chloride dissolve in the solution and are removed. They are then precipitated out of solution, dried, and heated under partial vacuum until the calcium chloride evaporates out of the mix. Temperatures of this range will cause the hydrated aluminum chloride to become [[alumina]], releasing water and hydrogen chloride in the process:

: 2 AlCl3.6 H2O ==> Al2O3 + 6 HCl + 3 H2O

The water and hydrogen chloride are separated from the calcium chloride and fed back into the system. The calcium chloride is then electrolyzed into metallic calcium and chlorine. A portion of the recovered water is then [[Water Splitting|split]] into hydrogen and oxygen. The hydrogen component is reacted with the evolved chlorine to produce hydrogen chloride, which is then fed back into the main system.

=== Direct Calcium Aluminate / Alumina Reduction ===

Calcium Aluminate (see above for production) could be simply melted and electrolyzed directly, producing aluminum and calcium oxide.<ref>http://www.moonminer.com/Lunar_Aluminum.html</ref> This has two advantages. First, it requires no imported reagents, and second, only the aluminum is split, reducing the amount of energy needed. The disadvantage is that temperatures of approximately 1600 C are required, making electrode material of prime concern. Carbon electrodes could be utilized at those temperatures, but the anode would continually wear away as oxygen was produced around it, creating carbon monoxide. The carbon would need to be [[Lunar Carbon Production|recovered]] and new anodes made from it. This effectively means that a rare reagent is needed, negating the process's first stated advantage. Finding an anode material that would produce oxygen without wearing away at those temperatures could be quite difficult.

Alumina could also be directly melted and electrolyzed in the same fashion. However, this would require temperatures of approximately 2000 C, bringing with it again the issue of electrode material.

=== Hall-Heroult Process ===

In the Hall-Heroult process, alumina is dissolved in molten cryolite ([[Sodium]] hexafluoroaluminate, Na3 AlF6 ) around 1400 ºC. This mix is electrolyzed to separate two byproducts: aluminium and CO2. The carbon comes from the consumption of the carbon anode.

This procedure is used extensively on earth for aluminum production, and as such has the advantage of being a very mature technology. The biggest issue is the consumption of the anode, which would require the produced carbon monoxide to be captured, [[Lunar Carbon Production|converted back into carbon]], and recast into new anodes; an energy intensive process. It is not known if an inert(non-consumable) anode material can be found that would work under these conditions.<ref>http://en.wikipedia.org/wiki/Hall-H%C3%A9roult_process</ref>

=== Subchloride Process ===

In the subchloride process [[alumina]] is reacted with [[carbon]] and [[chlorine]] to yield [[Al]][[Cl]]3 and [[Carbon dioxide |CO2]]. The [[Al]][[Cl]]3 is electrolyzed to produce [[Aluminum]] while recovering the [[chlorine]]. This has the advantage that conventional [[carbon]] electrodes can be used continuously, as the produced [[chlorine]] does not react with them. However, the [[Carbon dioxide |CO2]] byproduct must be [[Lunar Carbon Production|recycled]], adding extra complexity and energy requirements to the system. This makes it similar to the Hall-Heroult process in difficulty, except for two advantages. First, the recycled carbon can be directly used in powdered form, it does not need to be recast into electrodes. Second, due to the low melting point of [[Al]][[Cl]]3 (120 C), the process does not require significant energy to melt, and is more easily handled. <ref>http://www.moonminer.com/Lunar_Aluminum.html </ref>

=== Carbothermal Reduction ===

Carbon reduction of Alumina is impossible under normal smelting conditions, due to [[aluminum]]s high reduction potential. However, Alumina could be mixed with silica and carbon and melted near 2000 C, which would form an aluminium-silicon alloy, as well as CO2. This could be separated by cooling the Al-Si mixture to 700 -1000 C and allowing the silicon to solidify and settle out of the melt.<ref>http://www.moonminer.com/Lunar_Aluminum.html </ref>

An alternate process involves alumina and carbon processed at high temperatures and low pressure into Al4C3 and carbon monoxide.<ref> [http://en.wikipedia.org/wiki/Aluminium ''Aluminum'' section ''Production and refinement''] </ref>
<ref> [http://www.moonminer.com/Lunar_Aluminum.html ''Lunar Aluminum'' at ''Moondust index''] </ref> This breaks down into Aluminum and Carbon between 1900 and 2000 C.<ref> [http://en.wikipedia.org/wiki/Aluminum_carbide ''Aluminium carbide'' at ''Wikipedia''] </ref>.

In either case, CO2/CO would have to be recovered and and the [[Lunar Carbon Production|carbon recycled]].

== See Also ==

*[[Aluminium]]
*[[Magma Electrolysis]]
*[[ISRU]]
*[[List of Proposed Metal Production Methods]]

== References ==
<references/>

[[Category:Industrial Production]]

Lunar Aluminum Production

2011-09-08T21:01:38Z

205.208.203.59: /* Anorthite Production */

Since Luna lacks any known deposits of bauxite, the ore most commonly used on earth for aluminum production, [[anorthite]] (CaAl2Si2O8) is most commonly proposed as a lunar substitute.<ref>http://www.permanent.com/l-minera.htm#aluminum</ref> [[Anorthite]] could be separated from the lunar highland material [[Anorthosite]] with mechanical methods. It could then be reduced through various chemical and electrochemical methods to produce [[aluminum]].

== Anorthite Production ==

The [[Anorthosite]] which makes up the Lunar highlands is a mix of [[Plagioclase]]s, [[Olivine]]s, and [[Pyroxene]]s. To separate the [[anorthite]], [[anorthosite]] must be ground. Then, magnetic separation could leave the non-magnetic anorthite.

The magnetic materials ([[Ilmenite]] and iron oxide) could be stored for production of [[titanium]], [[iron]], and [[oxygen]].

== Anorthite Refinement ==

===Direct Reduction===
Main Article: [[FFC Cambridge Process#Aluminum/Silicon/Calcium Production from Anorthite|FFC Cambridge Process]]

[[Anorthite]] could be directly reduced to its component metals using the [[FFC Cambridge Process]]. The [[Anorthite]] is pressed/sintered into a cathode, which is placed in a bath of molten calcium chloride and electrolyzed. The oxygen is stripped out, leaving behind [[Aluminum]], [[Calcium]], and [[Silicon]].

This process has the advantage of inherent simplicity, as well as having only one component to recycle, the calcium chloride, which does not react chemically with the inputs, making recovery much simpler. In addition, this process runs at lower temperatures (900º-1100º C) than many other electrolysis procedures, and inert(non-consumable) anodes have been successfully demonstrated with it<ref>http://www.lpi.usra.edu/meetings/roundtable2006/pdf/tripuraneni.pdf</ref>. On the downside, energy must be expended to split all the components of the [[Anorthite]], not just the [[aluminum]]. Splitting the silicon and calcium adds a significant amount of extra energy to the process, as both of them are strong reducers. However, if the silicon and calcium byproducts were needed for other purposes (calcium is a good [[Electrical Conductors|electrical conductor]], and silicon could be used for solar panels or [[In-Situ Propellant Production#Silicon|rocket fuel]]), this extra energy cost may not be an issue.

=== Alumina Production ===

Many processes used on earth or proposed for Lunar use require [[Alumina]] ([[Aluminum|Al]]2[[Oxygen|O]]3) as an input. On Earth, alumina is produced from bauxite through the Bayer process. As this process is not feasible using Anorthite, another method must be utilized.

====Vacuum Distillation====

[[Alumina]] could be produced from Anorthite by boiling out the impurities between 1500 ºC - 2000 ºC under vacuum conditions. The resulting material would be calcium aluminate ([[Ca]][[Al]][[O]]4). Raising the temperature further could cause [[alumina]] to volatilize as well. <ref>http://www.moonminer.com/Lunar_Aluminum.html</ref>

====Sulfuric Acid Leaching====

Another method is to produce calcium aluminate as outlined previously, which is then leached in sulfuric acid, resulting in the following reaction:

[[Ca]][[Al]]2[[O]]4 + [[Sulfuric Acid |4H2SO4]] ==> [[Ca]][[S]][[O]]4 + [[Al]]2([[S]][[O]]4)3 + 4[[water |H2O]]

Aluminium sulfate in hexadecahydrate form ([[Al]]2([[S]][[O]]4)3) is then separated from calcium sulphate ([[Ca]][[S]][[O]]4 + [[Al]]2([[S]][[O]]4)3) by filtering and from water by evaporation (and then recovered).

Finally Alumina is obtained by roasting the aluminum sulfate releasing [[S]]2.<ref>http://www.moonminer.com/Lunar_Aluminum.html</ref>

====Hydrochloric Acid Leaching====
Another option is to react [[Anorthite]] with hydrochloric acid, which results in following reaction:

: [[Ca]][[Al]]2[[Si]]2[[O]]8 + 8 [[H]][[Cl]] + 2 [[H]]2[[O]]==> [[Ca]][[Cl]]2 + 2 [[Al]][[Cl]]3.6 [[H]]2[[O]] + 2 [[Si]][[O]]2

The calcium chloride and hydrated aluminum chloride dissolve in the solution and are removed. They are then precipitated out of solution, dried, and heated under partial vacuum until the calcium chloride evaporates out of the mix. Temperatures of this range will cause the hydrated aluminum chloride to become [[alumina]], releasing water and hydrogen chloride in the process:

: 2 AlCl3.6 H2O ==> Al2O3 + 6 HCl + 3 H2O

The water and hydrogen chloride are separated from the calcium chloride and fed back into the system. The calcium chloride is then electrolyzed into metallic calcium and chlorine. A portion of the recovered water is then [[Water Splitting|split]] into hydrogen and oxygen. The hydrogen component is reacted with the evolved chlorine to produce hydrogen chloride, which is then fed back into the main system.

=== Direct Calcium Aluminate / Alumina Reduction ===

Calcium Aluminate (see above for production) could be simply melted and electrolyzed directly, producing aluminum and calcium oxide.<ref>http://www.moonminer.com/Lunar_Aluminum.html</ref> This has two advantages. First, it requires no imported reagents, and second, only the aluminum is split, reducing the amount of energy needed. The disadvantage is that temperatures of approximately 1600 C are required, making electrode material of prime concern. Carbon electrodes could be utilized at those temperatures, but the anode would continually wear away as oxygen was produced around it, creating carbon monoxide. The carbon would need to be [[Lunar Carbon Production|recovered]] and new anodes made from it. This effectively means that a rare reagent is needed, negating the process's first stated advantage. Finding an anode material that would produce oxygen without wearing away at those temperatures could be quite difficult.

Alumina could also be directly melted and electrolyzed in the same fashion. However, this would require temperatures of approximately 2000 C, bringing with it again the issue of electrode material.

=== Hall-Heroult Process ===

In the Hall-Heroult process, alumina is dissolved in molten cryolite ([[Sodium]] hexafluoroaluminate, Na3 AlF6 ) around 1400 ºC. This mix is electrolyzed to separate two byproducts: aluminium and CO2. The carbon comes from the consumption of the carbon anode.

This procedure is used extensively on earth for aluminum production, and as such has the advantage of being a very mature technology. The biggest issue is the consumption of the anode, which would require the produced carbon monoxide to be captured, [[Lunar Carbon Production|converted back into carbon]], and recast into new anodes; an energy intensive process. It is not known if an inert(non-consumable) anode material can be found that would work under these conditions.<ref>http://en.wikipedia.org/wiki/Hall-H%C3%A9roult_process</ref>

=== Subchloride Process ===

In the subchloride process [[alumina]] is reacted with [[carbon]] and [[chlorine]] to yield [[Al]][[Cl]]3 and [[Carbon dioxide |CO2]]. The [[Al]][[Cl]]3 is electrolyzed to produce [[Aluminum]] while recovering the [[chlorine]]. This has the advantage that conventional [[carbon]] electrodes can be used continuously, as the produced [[chlorine]] does not react with them. However, the [[Carbon dioxide |CO2]] byproduct must be [[Lunar Carbon Production|recycled]], adding extra complexity and energy requirements to the system. This makes it similar to the Hall-Heroult process in difficulty, except for two advantages. First, the recycled carbon can be directly used in powdered form, it does not need to be recast into electrodes. Second, due to the low melting point of [[Al]][[Cl]]3 (120 C), the process does not require significant energy to melt, and is more easily handled. <ref>http://www.moonminer.com/Lunar_Aluminum.html </ref>

=== Carbothermal Reduction ===

Carbon reduction of Alumina is impossible under normal smelting conditions, due to [[aluminum]]s high reduction potential. However, Alumina could be mixed with silica and carbon and melted near 2000 C, which would form an aluminium-silicon alloy, as well as CO2. This could be separated by cooling the Al-Si mixture to 700 -1000 C and allowing the silicon to solidify and settle out of the melt.<ref>http://www.moonminer.com/Lunar_Aluminum.html </ref>

An alternate process involves alumina and carbon processed at high temperatures and low pressure into Al4C3 and carbon monoxide.<ref> [http://en.wikipedia.org/wiki/Aluminium ''Aluminum'' section ''Production and refinement''] </ref>
<ref> [http://www.moonminer.com/Lunar_Aluminum.html ''Lunar Aluminum'' at ''Moondust index''] </ref> This breaks down into Aluminum and Carbon between 1900 and 2000 C.<ref> [http://en.wikipedia.org/wiki/Aluminum_carbide ''Aluminium carbide'' at ''Wikipedia''] </ref>.

In either case, CO2/CO would have to be recovered and and the [[Lunar Carbon Production|carbon recycled]].

== See Also ==

*[[Aluminium]]
*[[Magma Electrolysis]]
*[[ISRU]]
*[[List of Proposed Metal Production Methods]]

== References ==
<references/>

[[Category:Industrial Production]]

Lunar Aluminum Production

2011-09-08T21:01:03Z

205.208.203.59: /* Anorthite Production */

Since Luna lacks any known deposits of bauxite, the ore most commonly used on earth for aluminum production, [[anorthite]] (CaAl2Si2O8) is most commonly proposed as a lunar substitute.<ref>http://www.permanent.com/l-minera.htm#aluminum</ref> [[Anorthite]] could be separated from the lunar highland material [[Anorthosite]] with mechanical methods. It could then be reduced through various chemical and electrochemical methods to produce [[aluminum]].

== Anorthite Production ==

The [[Anorthosite]] which makes up the Lunar highlands is a mix of [[Plagioclase]]s, [[Olivine]]s, and [[Pyroxene]]s. To separate the [[anorthite]], [[anorthosite]] must be ground. Then, magnetic separation could leave the non-magnetic anorthite.

The magnetic materials ([[Ilmenite]] and iron oxide) could be stored for production of [[titanium]], [[iron]] and [[oxygen]].

== Anorthite Refinement ==

===Direct Reduction===
Main Article: [[FFC Cambridge Process#Aluminum/Silicon/Calcium Production from Anorthite|FFC Cambridge Process]]

[[Anorthite]] could be directly reduced to its component metals using the [[FFC Cambridge Process]]. The [[Anorthite]] is pressed/sintered into a cathode, which is placed in a bath of molten calcium chloride and electrolyzed. The oxygen is stripped out, leaving behind [[Aluminum]], [[Calcium]], and [[Silicon]].

This process has the advantage of inherent simplicity, as well as having only one component to recycle, the calcium chloride, which does not react chemically with the inputs, making recovery much simpler. In addition, this process runs at lower temperatures (900º-1100º C) than many other electrolysis procedures, and inert(non-consumable) anodes have been successfully demonstrated with it<ref>http://www.lpi.usra.edu/meetings/roundtable2006/pdf/tripuraneni.pdf</ref>. On the downside, energy must be expended to split all the components of the [[Anorthite]], not just the [[aluminum]]. Splitting the silicon and calcium adds a significant amount of extra energy to the process, as both of them are strong reducers. However, if the silicon and calcium byproducts were needed for other purposes (calcium is a good [[Electrical Conductors|electrical conductor]], and silicon could be used for solar panels or [[In-Situ Propellant Production#Silicon|rocket fuel]]), this extra energy cost may not be an issue.

=== Alumina Production ===

Many processes used on earth or proposed for Lunar use require [[Alumina]] ([[Aluminum|Al]]2[[Oxygen|O]]3) as an input. On Earth, alumina is produced from bauxite through the Bayer process. As this process is not feasible using Anorthite, another method must be utilized.

====Vacuum Distillation====

[[Alumina]] could be produced from Anorthite by boiling out the impurities between 1500 ºC - 2000 ºC under vacuum conditions. The resulting material would be calcium aluminate ([[Ca]][[Al]][[O]]4). Raising the temperature further could cause [[alumina]] to volatilize as well. <ref>http://www.moonminer.com/Lunar_Aluminum.html</ref>

====Sulfuric Acid Leaching====

Another method is to produce calcium aluminate as outlined previously, which is then leached in sulfuric acid, resulting in the following reaction:

[[Ca]][[Al]]2[[O]]4 + [[Sulfuric Acid |4H2SO4]] ==> [[Ca]][[S]][[O]]4 + [[Al]]2([[S]][[O]]4)3 + 4[[water |H2O]]

Aluminium sulfate in hexadecahydrate form ([[Al]]2([[S]][[O]]4)3) is then separated from calcium sulphate ([[Ca]][[S]][[O]]4 + [[Al]]2([[S]][[O]]4)3) by filtering and from water by evaporation (and then recovered).

Finally Alumina is obtained by roasting the aluminum sulfate releasing [[S]]2.<ref>http://www.moonminer.com/Lunar_Aluminum.html</ref>

====Hydrochloric Acid Leaching====
Another option is to react [[Anorthite]] with hydrochloric acid, which results in following reaction:

: [[Ca]][[Al]]2[[Si]]2[[O]]8 + 8 [[H]][[Cl]] + 2 [[H]]2[[O]]==> [[Ca]][[Cl]]2 + 2 [[Al]][[Cl]]3.6 [[H]]2[[O]] + 2 [[Si]][[O]]2

The calcium chloride and hydrated aluminum chloride dissolve in the solution and are removed. They are then precipitated out of solution, dried, and heated under partial vacuum until the calcium chloride evaporates out of the mix. Temperatures of this range will cause the hydrated aluminum chloride to become [[alumina]], releasing water and hydrogen chloride in the process:

: 2 AlCl3.6 H2O ==> Al2O3 + 6 HCl + 3 H2O

The water and hydrogen chloride are separated from the calcium chloride and fed back into the system. The calcium chloride is then electrolyzed into metallic calcium and chlorine. A portion of the recovered water is then [[Water Splitting|split]] into hydrogen and oxygen. The hydrogen component is reacted with the evolved chlorine to produce hydrogen chloride, which is then fed back into the main system.

=== Direct Calcium Aluminate / Alumina Reduction ===

Calcium Aluminate (see above for production) could be simply melted and electrolyzed directly, producing aluminum and calcium oxide.<ref>http://www.moonminer.com/Lunar_Aluminum.html</ref> This has two advantages. First, it requires no imported reagents, and second, only the aluminum is split, reducing the amount of energy needed. The disadvantage is that temperatures of approximately 1600 C are required, making electrode material of prime concern. Carbon electrodes could be utilized at those temperatures, but the anode would continually wear away as oxygen was produced around it, creating carbon monoxide. The carbon would need to be [[Lunar Carbon Production|recovered]] and new anodes made from it. This effectively means that a rare reagent is needed, negating the process's first stated advantage. Finding an anode material that would produce oxygen without wearing away at those temperatures could be quite difficult.

Alumina could also be directly melted and electrolyzed in the same fashion. However, this would require temperatures of approximately 2000 C, bringing with it again the issue of electrode material.

=== Hall-Heroult Process ===

In the Hall-Heroult process, alumina is dissolved in molten cryolite ([[Sodium]] hexafluoroaluminate, Na3 AlF6 ) around 1400 ºC. This mix is electrolyzed to separate two byproducts: aluminium and CO2. The carbon comes from the consumption of the carbon anode.

This procedure is used extensively on earth for aluminum production, and as such has the advantage of being a very mature technology. The biggest issue is the consumption of the anode, which would require the produced carbon monoxide to be captured, [[Lunar Carbon Production|converted back into carbon]], and recast into new anodes; an energy intensive process. It is not known if an inert(non-consumable) anode material can be found that would work under these conditions.<ref>http://en.wikipedia.org/wiki/Hall-H%C3%A9roult_process</ref>

=== Subchloride Process ===

In the subchloride process [[alumina]] is reacted with [[carbon]] and [[chlorine]] to yield [[Al]][[Cl]]3 and [[Carbon dioxide |CO2]]. The [[Al]][[Cl]]3 is electrolyzed to produce [[Aluminum]] while recovering the [[chlorine]]. This has the advantage that conventional [[carbon]] electrodes can be used continuously, as the produced [[chlorine]] does not react with them. However, the [[Carbon dioxide |CO2]] byproduct must be [[Lunar Carbon Production|recycled]], adding extra complexity and energy requirements to the system. This makes it similar to the Hall-Heroult process in difficulty, except for two advantages. First, the recycled carbon can be directly used in powdered form, it does not need to be recast into electrodes. Second, due to the low melting point of [[Al]][[Cl]]3 (120 C), the process does not require significant energy to melt, and is more easily handled. <ref>http://www.moonminer.com/Lunar_Aluminum.html </ref>

=== Carbothermal Reduction ===

Carbon reduction of Alumina is impossible under normal smelting conditions, due to [[aluminum]]s high reduction potential. However, Alumina could be mixed with silica and carbon and melted near 2000 C, which would form an aluminium-silicon alloy, as well as CO2. This could be separated by cooling the Al-Si mixture to 700 -1000 C and allowing the silicon to solidify and settle out of the melt.<ref>http://www.moonminer.com/Lunar_Aluminum.html </ref>

An alternate process involves alumina and carbon processed at high temperatures and low pressure into Al4C3 and carbon monoxide.<ref> [http://en.wikipedia.org/wiki/Aluminium ''Aluminum'' section ''Production and refinement''] </ref>
<ref> [http://www.moonminer.com/Lunar_Aluminum.html ''Lunar Aluminum'' at ''Moondust index''] </ref> This breaks down into Aluminum and Carbon between 1900 and 2000 C.<ref> [http://en.wikipedia.org/wiki/Aluminum_carbide ''Aluminium carbide'' at ''Wikipedia''] </ref>.

In either case, CO2/CO would have to be recovered and and the [[Lunar Carbon Production|carbon recycled]].

== See Also ==

*[[Aluminium]]
*[[Magma Electrolysis]]
*[[ISRU]]
*[[List of Proposed Metal Production Methods]]

== References ==
<references/>

[[Category:Industrial Production]]

Roof Support

2011-09-02T07:58:05Z

205.208.203.59: /* Supporting Regolith */ reformatted table, added missing data

[[Image:ArchDorm01.jpg|frame| Architecture as Mole Hills, Standard dorm room]]
 

{|align=right
|__TOC__
|}

One serious lunar problem will be your roof falling in on you.

== Using the roof for radiation and heat shielding ==

The need for radiation shielding for lunar settlement occupants means that there will be significant mass on the roof of all buildings used for long term occupancy. Much of the electronic equipment will need shielding too. This shielding could be in the form of lunar regolith as suggested in [[Architecture as Mole Hills]] and [[Architecture as Tent City]] or material brought from Earth, but it must be provided on any structure where people will stay longer than a few weeks.

Also, if your massive radiation shielding roof falls in on you, you will be in real trouble, so inflated room systems must allow for emergency exit even will all the air pressure lost.

==Inflatable Housing==

Since the interior living space must be at considerably higher air pressure than the exterior, it is only logical to use the force this pressure exerts on the outside walls to help support the weight of the roof. The rooms then become like balloons getting much of their strength from their internal pressure. The amount of mass an inflated roof will support is directly related to the internal pressure.

A major problem comes when you lose the pressure and the massive roof falls in on you. Loss of pressure, or blow out, is a real possibility due to meteorites, ejecta, landing accidents, or industrial accidents. Even if you can get into an environmental suit, you will have to get to safety before your air supply runs out.

===Pressure Considerations===

One of the most important considerations in the design of a lunar settlement will be the internal air pressure.

====High Pressure====

High air pressure, that is Earth normal 101 kpa (14.2 PSI, makes the living space more Earth like. People and plants accommodate to living on the Moon easily and food is easy to cook.

But, spacesuits must be at low pressure for the joints to work with acceptable amounts of efforts. Any time a persons moves from a high pressure to a low pressure environment, you risk nitrogen forming bubbles in your blood; a conditions called the bends. For the body to accommodate from normal air pressure to a low spacesuit pressure can take as long as an overnight stay in a low pressure chamber.

====Low Pressure====

Low air pressure, with adequate oxygen content, allows the human body to accommodation to spacesuit pressures in only a few minutes or just seconds in an emergency. Ranges from 74 kPa (10.2 psi) down to 33.5 kpi (4.7 psi) have been discussed for lunar settlements. The human body will simply never fully accommodate pressures below about 30 kPascal (4.2 psi).

At low pressures you can use 100% oxygen which greatly simplifies the entire life support system. Testing this type of system is very dangerous and has resulted in two serious fires. The key safety concept is that if the partial pressure of oxygen exceeds Earth normal of 22 kPascal (3.0 psi) then substancial fire control efforts are required.

The long term health effects of low pressure are not fully known for people or for plants. Any agricultural areas may need additional CO2, humidity, and nitrogen compared the people living areas.

Low pressure also saves the cost of shipping a large mass of bulk nitrogen from Earth. This could be a very important cost consideration in early lunar settlements.

Water boils at such a low temperature at low atmospheric pressure that cooking is difficult. You simply cannot get things hot enough to really taste right. A cup of tea that you can stir with your finger is simply not worth drinking.

Also low air pressure will not support as thick a layer of protecting regolith over inflated buildings.

====Supporting Regolith====

Here are some of present ideas for lunar settlement air pressures and how much regolith they will support:

{| border=1
! colspan="2" | Pressure !! colspan="2" | Boiling Point Of Water !! Regolith Needed to Equal Atmospheric Shielding !! Maximum Regolith Supported !!Comment
|-
| kPa || psi || °C || °F || m || m ||
|-
| 101.3 || 14.2 || 100 || 212 || 5.4 || 32 || Sea Level, ISS body
|-
| 84 || 12.17 || 95 || 203 || 4.5 || 27 || Denver, a high altitude city
|-
| 81.4 || 11.74 || 94 || 201 || 4.3 || 26 || Mexico City, a high altitude city
|-
| 74.0 || 10.2 || 92 || 197 || 4.0 || 24 || Open airplane, ISS ports
|-
| 59.1 || 8.3 || 86 || 187 || 3.2 || 19 || ISS spacesuit
|-
| 33.5 || 4.7 || 72 || 162 || 1.8 || 10 || Apollo spacesuit
|-
| 30.6 || 4.3 || 70 || 158 || 1.6 || 9.9 || Shuttle spacesuit
|-
| 26.0 || 3.65 || 66 || 152 || 1.4 || 8.4 || Top of Mount Everest
|-
| 10.0 || 1.5 || 46 || 115 || 0.5 || 3.2 || 1/10 Atm, 16,000 m, unconscious in 10 sec
|}

The Regolith Shield column shows how much lunar regolith is needed to provide radiation shielding equivalent to the air above your head at these locations on Earth. The Regolith Support column shows how much lunar regolith can be supported on the Moon by that level of internal pressure.

These calculations are based on the following parameters:

{| border=1
| density of packed regolith || 1.9 || g/cm^3 || Used for this calculation
|-
| density of loose regolith || 1.5 || g/cm^3 || just poured in a pile
|-
| Lunar gravity || 1.63 || m/s^2 || about 1/6 Earth
|-
| Human body temperature || 37.0 || C || 98.6 F

|}

It is important to note that the internal pressure inside a living area has plenty of force to support a substantial thickness of lunar regolith above it for radiation and thermal shielding even if low pressures are used.

==Safety rule==

The roof cave in problem will require a strong safety rule that will greatly affect the design of lunar buildings. One possible rule is this:

;Roof Support Rule: With the internal building pressure completely lost, a person wearing an environmental suit must have enough clearance to crawl to safety even if a second person is lying immobile in the evacuation path.

===Rule's effects===

Such a rule, combined with the very high cost of bringing mass from Earth, will make large open rooms very rare on the Moon. Rooms and even halls will require internal columns or bearing walls to hold up the roof with a loss of pressure. Most rooms will have to be narrow in at least one direction and will have to have central support for the roof.

What will be very difficult to build will be very large areas such as meeting rooms and mess halls. They will probably need internal supports.

The absence of large rooms will make living in a lunar settlement even more claustrophobic. This effect might be countered with panoramic vistas of open space on external monitors, via [[periscope windows|pariscope style windows]], or with viewing doom rooms.

----

==Alternative Roof Supports==

Once even some industrial capacity is established on the Moon, all lunar material structures will be preferable to inflated structures that require large amounts of materials from Earth.

[[Image:Under Roof Sketch 18 Sept 2007.png|thumb|320px|Elevated roof concept]]

===Hard Roof===

If a practical lunar cement can be developed, then we can avoid pressure supported roof problems completely.

Earth cements cannot be used as they are water based and the minerals that they are made from are not available on the Moon.

===Alternate Roof Support===

There is an alternate form of roof support discussed within an article on [[Sintered Brick Construction]].

----

{{Hazards}}

[[Category:Architecture]]
[[Category:Hazards]]

Lunar Aluminum Production

2011-08-31T02:06:09Z

205.208.203.59: /* Future Hall-Heroult Adaptation */

Since Luna lacks any known deposits of bauxite, the ore most commonly used on earth for aluminum production, [[anorthite]] (CaAl2Si2O8) is most commonly proposed as a lunar substitute.<ref>http://www.permanent.com/l-minera.htm#aluminum</ref> [[Anorthite]] could be separated from the lunar highland material [[Anorthosite]] with mechanical methods. It could then be reduced through various chemical and electrochemical methods to produce [[aluminum]].

== Anorthite Production ==

The [[Anorthosite]] which makes up the Lunar highlands is a mix of [[Plagioclase]]s, [[Olivine]]s, and [[Pyroxene]]s. To separate the [[anorthite]], [[anorthosite]] must be ground. Then, magnetic separation could leave the non-magnetic anorthite.

The magnetic materials ([[Ilmenite]] and iron oxide) could be stored for production of [[Titanium]], [[iron]] and [[oxygen]].

== Anorthite Refinement ==

===Direct Reduction===
Main Article: [[FFC Cambridge Process#Aluminum/Silicon/Calcium Production from Anorthite|FFC Cambridge Process]]

[[Anorthite]] could be directly reduced to its component metals using the [[FFC Cambridge Process]]. The [[Anorthite]] is pressed/sintered into a cathode, which is placed in a bath of molten calcium chloride and electrolyzed. The oxygen is stripped out, leaving behind [[Aluminum]], [[Calcium]], and [[Silicon]].

This process has the advantage of inherent simplicity, as well as having only one component to recycle, the calcium chloride, which does not react chemically with the inputs, making recovery much simpler. In addition, this process runs at lower temperatures (900º-1100º C) than many other electrolysis procedures, and inert(non-consumable) anodes have been successfully demonstrated with it<ref>http://www.lpi.usra.edu/meetings/roundtable2006/pdf/tripuraneni.pdf</ref>. On the downside, energy must be expended to split all the components of the [[Anorthite]], not just the [[aluminum]]. Splitting the silicon and calcium adds a significant amount of extra energy to the process, as both of them are strong reducers. However, if the silicon and calcium byproducts were needed for other purposes (calcium is a good [[Electrical Conductors|electrical conductor]], and silicon could be used for solar panels or [[In-Situ Propellant Production#Silicon|rocket fuel]]), this extra energy cost may not be an issue.

=== Alumina Production ===

Many processes used on earth or proposed for Lunar use require [[Alumina]] ([[Aluminum|Al]]2[[Oxygen|O]]3) as an input. On Earth, alumina is produced from bauxite through the Bayer process. As this process is not feasible using Anorthite, another method must be utilized.

====Vacuum Distillation====

[[Alumina]] could be produced from Anorthite by boiling out the impurities between 1500 ºC - 2000 ºC under vacuum conditions. The resulting material would be calcium aluminate ([[Ca]][[Al]][[O]]4). Raising the temperature further could cause [[alumina]] to volatilize as well. <ref>http://www.moonminer.com/Lunar_Aluminum.html</ref>

====Sulfuric Acid Leaching====

Another method is to produce calcium aluminate as outlined previously, which is then leached in sulfuric acid, resulting in the following reaction:

[[Ca]][[Al]]2[[O]]4 + [[Sulfuric Acid |4H2SO4]] ==> [[Ca]][[S]][[O]]4 + [[Al]]2([[S]][[O]]4)3 + 4[[water |H2O]]

Aluminium sulfate in hexadecahydrate form ([[Al]]2([[S]][[O]]4)3) is then separated from calcium sulphate ([[Ca]][[S]][[O]]4 + [[Al]]2([[S]][[O]]4)3) by filtering and from water by evaporation (and then recovered).

Finally Alumina is obtained by roasting the aluminum sulfate releasing [[S]]2.<ref>http://www.moonminer.com/Lunar_Aluminum.html</ref>

====Hydrochloric Acid Leaching====
Another option is to react [[Anorthite]] with hydrochloric acid, which results in following reaction:

: [[Ca]][[Al]]2[[Si]]2[[O]]8 + 8 [[H]][[Cl]] + 2 [[H]]2[[O]]==> [[Ca]][[Cl]]2 + 2 [[Al]][[Cl]]3.6 [[H]]2[[O]] + 2 [[Si]][[O]]2

The calcium chloride and hydrated aluminum chloride dissolve in the solution and are removed. They are then precipitated out of solution, dried, and heated under partial vacuum until the calcium chloride evaporates out of the mix. Temperatures of this range will cause the hydrated aluminum chloride to become [[alumina]], releasing water and hydrogen chloride in the process:

: 2 AlCl3.6 H2O ==> Al2O3 + 6 HCl + 3 H2O

The water and hydrogen chloride are separated from the calcium chloride and fed back into the system. The calcium chloride is then electrolyzed into metallic calcium and chlorine. A portion of the recovered water is then [[Water Splitting|split]] into hydrogen and oxygen. The hydrogen component is reacted with the evolved chlorine to produce hydrogen chloride, which is then fed back into the main system.

=== Direct Calcium Aluminate / Alumina Reduction ===

Calcium Aluminate (see above for production) could be simply melted and electrolyzed directly, producing aluminum and calcium oxide.<ref>http://www.moonminer.com/Lunar_Aluminum.html</ref> This has two advantages. First, it requires no imported reagents, and second, only the aluminum is split, reducing the amount of energy needed. The disadvantage is that temperatures of approximately 1600 C are required, making electrode material of prime concern. Carbon electrodes could be utilized at those temperatures, but the anode would continually wear away as oxygen was produced around it, creating carbon monoxide. The carbon would need to be [[Lunar Carbon Production|recovered]] and new anodes made from it. This effectively means that a rare reagent is needed, negating the process's first stated advantage. Finding an anode material that would produce oxygen without wearing away at those temperatures could be quite difficult.

Alumina could also be directly melted and electrolyzed in the same fashion. However, this would require temperatures of approximately 2000 C, bringing with it again the issue of electrode material.

=== Hall-Heroult Process ===

In the Hall-Heroult process, alumina is dissolved in molten cryolite ([[Sodium]] hexafluoroaluminate, Na3 AlF6 ) around 1400 ºC. This mix is electrolyzed to separate two byproducts: aluminium and CO2. The carbon comes from the consumption of the carbon anode.

This procedure is used extensively on earth for aluminum production, and as such has the advantage of being a very mature technology. The biggest issue is the consumption of the anode, which would require the produced carbon monoxide to be captured, [[Lunar Carbon Production|converted back into carbon]], and recast into new anodes; an energy intensive process. It is not known if an inert(non-consumable) anode material can be found that would work under these conditions.<ref>http://en.wikipedia.org/wiki/Hall-H%C3%A9roult_process</ref>

=== Subchloride Process ===

In the subchloride process [[alumina]] is reacted with [[carbon]] and [[chlorine]] to yield [[Al]][[Cl]]3 and [[Carbon dioxide |CO2]]. The [[Al]][[Cl]]3 is electrolyzed to produce [[Aluminum]] while recovering the [[chlorine]]. This has the advantage that conventional [[carbon]] electrodes can be used continuously, as the produced [[chlorine]] does not react with them. However, the [[Carbon dioxide |CO2]] byproduct must be [[Lunar Carbon Production|recycled]], adding extra complexity and energy requirements to the system. This makes it similar to the Hall-Heroult process in difficulty, except for two advantages. First, the recycled carbon can be directly used in powdered form, it does not need to be recast into electrodes. Second, due to the low melting point of [[Al]][[Cl]]3 (120 C), the process does not require significant energy to melt, and is more easily handled. <ref>http://www.moonminer.com/Lunar_Aluminum.html </ref>

=== Carbothermal Reduction ===

Carbon reduction of Alumina is impossible under normal smelting conditions, due to [[aluminum]]s high reduction potential. However, Alumina could be mixed with silica and carbon and melted near 2000 C, which would form an aluminium-silicon alloy, as well as CO2. This could be separated by cooling the Al-Si mixture to 700 -1000 C and allowing the silicon to solidify and settle out of the melt.<ref>http://www.moonminer.com/Lunar_Aluminum.html </ref>

An alternate process involves alumina and carbon processed at high temperatures and low pressure into Al4C3 and carbon monoxide.<ref> [http://en.wikipedia.org/wiki/Aluminium ''Aluminum'' section ''Production and refinement''] </ref>
<ref> [http://www.moonminer.com/Lunar_Aluminum.html ''Lunar Aluminum'' at ''Moondust index''] </ref> This breaks down into Aluminum and Carbon between 1900 and 2000 C.<ref> [http://en.wikipedia.org/wiki/Aluminum_carbide ''Aluminium carbide'' at ''Wikipedia''] </ref>.

In either case, CO2/CO would have to be recovered and and the [[Lunar Carbon Production|carbon recycled]].

== See Also ==

*[[Aluminium]]
*[[Magma Electrolysis]]
*[[ISRU]]
*[[List of Proposed Metal Production Methods]]

== References ==
<references/>

[[Category:Industrial Production]]

Lunar Aluminum Production

2011-08-31T02:01:51Z

205.208.203.59: /* Alumina Production */

Since Luna lacks any known deposits of bauxite, the ore most commonly used on earth for aluminum production, [[anorthite]] (CaAl2Si2O8) is most commonly proposed as a lunar substitute.<ref>http://www.permanent.com/l-minera.htm#aluminum</ref> [[Anorthite]] could be separated from the lunar highland material [[Anorthosite]] with mechanical methods. It could then be reduced through various chemical and electrochemical methods to produce [[aluminum]].

== Anorthite Production ==

The [[Anorthosite]] which makes up the Lunar highlands is a mix of [[Plagioclase]]s, [[Olivine]]s, and [[Pyroxene]]s. To separate the [[anorthite]], [[anorthosite]] must be ground. Then, magnetic separation could leave the non-magnetic anorthite.

The magnetic materials ([[Ilmenite]] and iron oxide) could be stored for production of [[Titanium]], [[iron]] and [[oxygen]].

== Anorthite Refinement ==

===Direct Reduction===
Main Article: [[FFC Cambridge Process#Aluminum/Silicon/Calcium Production from Anorthite|FFC Cambridge Process]]

[[Anorthite]] could be directly reduced to its component metals using the [[FFC Cambridge Process]]. The [[Anorthite]] is pressed/sintered into a cathode, which is placed in a bath of molten calcium chloride and electrolyzed. The oxygen is stripped out, leaving behind [[Aluminum]], [[Calcium]], and [[Silicon]].

This process has the advantage of inherent simplicity, as well as having only one component to recycle, the calcium chloride, which does not react chemically with the inputs, making recovery much simpler. In addition, this process runs at lower temperatures (900º-1100º C) than many other electrolysis procedures, and inert(non-consumable) anodes have been successfully demonstrated with it<ref>http://www.lpi.usra.edu/meetings/roundtable2006/pdf/tripuraneni.pdf</ref>. On the downside, energy must be expended to split all the components of the [[Anorthite]], not just the [[aluminum]]. Splitting the silicon and calcium adds a significant amount of extra energy to the process, as both of them are strong reducers. However, if the silicon and calcium byproducts were needed for other purposes (calcium is a good [[Electrical Conductors|electrical conductor]], and silicon could be used for solar panels or [[In-Situ Propellant Production#Silicon|rocket fuel]]), this extra energy cost may not be an issue.

=== Alumina Production ===

Many processes used on earth or proposed for Lunar use require [[Alumina]] ([[Aluminum|Al]]2[[Oxygen|O]]3) as an input. On Earth, alumina is produced from bauxite through the Bayer process. As this process is not feasible using Anorthite, another method must be utilized.

====Vacuum Distillation====

[[Alumina]] could be produced from Anorthite by boiling out the impurities between 1500 ºC - 2000 ºC under vacuum conditions. The resulting material would be calcium aluminate ([[Ca]][[Al]][[O]]4). Raising the temperature further could cause [[alumina]] to volatilize as well. <ref>http://www.moonminer.com/Lunar_Aluminum.html</ref>

====Sulfuric Acid Leaching====

Another method is to produce calcium aluminate as outlined previously, which is then leached in sulfuric acid, resulting in the following reaction:

[[Ca]][[Al]]2[[O]]4 + [[Sulfuric Acid |4H2SO4]] ==> [[Ca]][[S]][[O]]4 + [[Al]]2([[S]][[O]]4)3 + 4[[water |H2O]]

Aluminium sulfate in hexadecahydrate form ([[Al]]2([[S]][[O]]4)3) is then separated from calcium sulphate ([[Ca]][[S]][[O]]4 + [[Al]]2([[S]][[O]]4)3) by filtering and from water by evaporation (and then recovered).

Finally Alumina is obtained by roasting the aluminum sulfate releasing [[S]]2.<ref>http://www.moonminer.com/Lunar_Aluminum.html</ref>

====Hydrochloric Acid Leaching====
Another option is to react [[Anorthite]] with hydrochloric acid, which results in following reaction:

: [[Ca]][[Al]]2[[Si]]2[[O]]8 + 8 [[H]][[Cl]] + 2 [[H]]2[[O]]==> [[Ca]][[Cl]]2 + 2 [[Al]][[Cl]]3.6 [[H]]2[[O]] + 2 [[Si]][[O]]2

The calcium chloride and hydrated aluminum chloride dissolve in the solution and are removed. They are then precipitated out of solution, dried, and heated under partial vacuum until the calcium chloride evaporates out of the mix. Temperatures of this range will cause the hydrated aluminum chloride to become [[alumina]], releasing water and hydrogen chloride in the process:

: 2 AlCl3.6 H2O ==> Al2O3 + 6 HCl + 3 H2O

The water and hydrogen chloride are separated from the calcium chloride and fed back into the system. The calcium chloride is then electrolyzed into metallic calcium and chlorine. A portion of the recovered water is then [[Water Splitting|split]] into hydrogen and oxygen. The hydrogen component is reacted with the evolved chlorine to produce hydrogen chloride, which is then fed back into the main system.

=== Direct Calcium Aluminate / Alumina Reduction ===

Calcium Aluminate (see above for production) could be simply melted and electrolyzed directly, producing aluminum and calcium oxide.<ref>http://www.moonminer.com/Lunar_Aluminum.html</ref> This has two advantages. First, it requires no imported reagents, and second, only the aluminum is split, reducing the amount of energy needed. The disadvantage is that temperatures of approximately 1600 C are required, making electrode material of prime concern. Carbon electrodes could be utilized at those temperatures, but the anode would continually wear away as oxygen was produced around it, creating carbon monoxide. The carbon would need to be [[Lunar Carbon Production|recovered]] and new anodes made from it. This effectively means that a rare reagent is needed, negating the process's first stated advantage. Finding an anode material that would produce oxygen without wearing away at those temperatures could be quite difficult.

Alumina could also be directly melted and electrolyzed in the same fashion. However, this would require temperatures of approximately 2000 C, bringing with it again the issue of electrode material.

=== Future Hall-Heroult Adaptation ===

In the Hall-Heroult process, alumina is dissolved in molten cryolite ([[Sodium]] hexafluoroaluminate, Na3 AlF6 ) around 1400 ºC. This mix is electrolyzed to separate two byproducts: aluminium and CO2. The carbon comes from the consumption of the carbon anode.

This procedure is used extensively on earth for aluminum production, and as such has the advantage of being a very mature technology. The biggest issue is the consumption of the anode, which would require the produced carbon monoxide to be captured, [[Lunar Carbon Production|converted back into carbon]], and recast into new anodes; an energy intensive process. It is not known if an inert(non-consumable) anode material can be found that would work under these conditions.<ref>http://en.wikipedia.org/wiki/Hall-H%C3%A9roult_process</ref>

=== Subchloride Process ===

In the subchloride process [[alumina]] is reacted with [[carbon]] and [[chlorine]] to yield [[Al]][[Cl]]3 and [[Carbon dioxide |CO2]]. The [[Al]][[Cl]]3 is electrolyzed to produce [[Aluminum]] while recovering the [[chlorine]]. This has the advantage that conventional [[carbon]] electrodes can be used continuously, as the produced [[chlorine]] does not react with them. However, the [[Carbon dioxide |CO2]] byproduct must be [[Lunar Carbon Production|recycled]], adding extra complexity and energy requirements to the system. This makes it similar to the Hall-Heroult process in difficulty, except for two advantages. First, the recycled carbon can be directly used in powdered form, it does not need to be recast into electrodes. Second, due to the low melting point of [[Al]][[Cl]]3 (120 C), the process does not require significant energy to melt, and is more easily handled. <ref>http://www.moonminer.com/Lunar_Aluminum.html </ref>

=== Carbothermal Reduction ===

Carbon reduction of Alumina is impossible under normal smelting conditions, due to [[aluminum]]s high reduction potential. However, Alumina could be mixed with silica and carbon and melted near 2000 C, which would form an aluminium-silicon alloy, as well as CO2. This could be separated by cooling the Al-Si mixture to 700 -1000 C and allowing the silicon to solidify and settle out of the melt.<ref>http://www.moonminer.com/Lunar_Aluminum.html </ref>

An alternate process involves alumina and carbon processed at high temperatures and low pressure into Al4C3 and carbon monoxide.<ref> [http://en.wikipedia.org/wiki/Aluminium ''Aluminum'' section ''Production and refinement''] </ref>
<ref> [http://www.moonminer.com/Lunar_Aluminum.html ''Lunar Aluminum'' at ''Moondust index''] </ref> This breaks down into Aluminum and Carbon between 1900 and 2000 C.<ref> [http://en.wikipedia.org/wiki/Aluminum_carbide ''Aluminium carbide'' at ''Wikipedia''] </ref>.

In either case, CO2/CO would have to be recovered and and the [[Lunar Carbon Production|carbon recycled]].

== See Also ==

*[[Aluminium]]
*[[Magma Electrolysis]]
*[[ISRU]]
*[[List of Proposed Metal Production Methods]]

== References ==
<references/>

[[Category:Industrial Production]]

Lunar Carbon Production

2011-08-28T02:50:22Z

205.208.203.59:

== Introduction ==
Lunar [[carbon]] is found in trace amounts in the lunar regolith, where it can be extracted by heating (see [[Volatiles]]). This process results in a number of carbon compounds, chiefly carbon monoxide ([[Carbon|C]][[Oxygen|O]]), carbon dioxide ([[Carbon|C]][[Oxygen|O]]2), and methane ([[Carbon|C]][[Hydrogen|H]]4). It is desirable to produce elemental carbon from these feedstocks for production of lunar steel, as well as various other uses. In addition, processes to reduce these substances would be necessary in order to recycle carbon consumed in various industrial processes. A number of methods have been proposed for this.

== Carbon Monoxide Reduction ==
Carbon monoxide can be subjected to temperatures of around 700°C to produce carbon and carbon dioxide, a reaction that occurs in sooty chimneys.<ref>[http://www.moonminer.com/Basic-Chemistry-for-Moon-Miners.html Dietzler,Dave. "Basic Chemistry for Moon Miners" www.moonminer.com]</ref>:

2 [[Carbon Monoxide|CO]] ==> [[Carbon|C]] + [[Carbon Dioxide|CO2]]

This would recover half the carbon present in the gas. Further reduction of the carbon dioxide would be required to obtain the rest.

== Methane Reduction ==
Methane may be useful on its own as a feedstock for producing various hydrocarbons. If elemental carbon is desired, it can be subjected to thermal decomposition at high temperatures, producing [[hydrogen]] as a byproduct:
 [[Methane|CH4]] ==> [[Carbon|C]] + 2 [[Hydrogen|H]]2

Production of carbon and hydrogen in this manner has been tested with various catalysts. All had issues with carbon deposition fouling the catalyst surface. Uncatalyzed production seems to require temperatures significantly greater than 900°C <ref>Zabidi, N.A.M. and Zein, S.H.S. and Mohamed, A.R. [http://www.utp.edu.my/publications/platform/Platform%20v3n2.pdf#page=4 "Hydrogen production by catalytic decomposition of methane"] Technology Platform: Oilfield Gas Treatment and Utilization</ref>.

Uncatalyzed production has the advantage that any vessel capable of holding and heating the methane could be used as a reactor, even a simple pipe<ref>http://en.wikipedia.org/wiki/Sabatier_reaction#International_Space_Station_life_support</ref>, which could be periodically subjected to an auger to remove deposited carbon.

== Carbon Dioxide Reduction ==

=== Bosch Reaction ===

In the Bosch Reaction, carbon dioxide is reacted with hydrogen in the presence of an iron catalyst at temperatures between 530º and 730º C, producing carbon and water in a slightly exothermic process. The water is [[Water Splitting|split]], recovering the hydrogen and producing oxygen.

 [[Carbon Dioxide|CO2]] + 2 [[Hydrogen|H]]2 ==> [[Carbon|C]] + 2 [[Water|H2O]] (Bosch Reaction)
 2 [[Water|H2O]] ==> [[Oxygen|O]]2 + 2 [[Hydrogen|H]]2 ([[Water Splitting]])
 Net Reaction: [[Carbon Dioxide|CO2]] ==> [[Carbon|C]] + [[Oxygen|O]]2

This possesses the same disadvantage as low temperature methane decomposition, namely that the produced carbon builds up on the catalyst surface, reducing the efficiency. A combination of continuous mechanical scraping and large catalyst surfaces could make the reaction useable.

The bosch reaction is a subject of current research for space based carbon dioxide reduction<ref>http://people.oregonstate.edu/~atwaterj/h2o_gen.htm</ref>.

=== Sabatier Reaction ===
Another way to produce carbon from carbon dioxide is by use of the Sabatier reaction, which again involves reacting carbon dioxide with hydrogen, this time in the presence of a nickel catalyst. This process produces water and methane as reaction products:

 [[Carbon Dioxide|CO2]] + 4 [[Hydrogen|H]]2 ==> [[Methane|CH4]] + 2 [[Water|H2O]]

The water is split to recover hydrogen and oxygen, as in application of the Bosch reaction, and the methane is decomposed to carbon and hydrogen (see [[Lunar_Carbon_Production#Methane_Reduction|previous section]]).

The Sabatier Reaction is currently utilized on board the International Space Station, except that the methane produced is dumped overboard.

=== Direct CO2 Electrolysis ===
Another option is to directly electrolyze carbon dioxide<ref>[http://rtreport.ksc.nasa.gov/techreports/2002report/600%20Fluid%20Systems/609.html "Space Habitat Carbon Dioxide Electrolysis to Oxygen". Fluid System Technologies, 2002]</ref>, resulting in oxygen and carbon monoxide.
 
2 [[Carbon Dioxide|CO2]] ==> 2 [[Carbon Monoxide|CO]] + [[Oxygen|O]]2

An appropriate membrane could be utilized to separate the oxygen. The carbon monoxide could be reduced to carbon and carbon dioxide (see [[Lunar Carbon Production#Carbon Monoxide Reduction|previous section]]), returning the carbon dioxide to the cell for further reduction.

A number of processes utilizing carbon monoxide as a reducing agent have been proposed for lunar use. These processes would consume carbon monoxide and produce carbon dioxide. A direct electrolysis system could be used in this case on the produced carbon dioxide, with the carbon monoxide recirculated back into the system rather than reduced further.

=== Biological Reduction ===
Carbon could be produced by heating organic material in the absence of oxygen to produce charcoal. This would require some method of removing the ash which would inevitably be present.

Growing plants specifically to produce carbon in this fashion would probably be more energy intensive than other methods. However, processing of organic waste products into carbon presents an attractive recycling mechanism, as it can be utilized on the non-edible parts of food plants and even human feces. This process would most likely be carried out in conjunction with other carbon production methods, as the human population would need to be quite high for it to supply all the carbon.

== References ==

<references/>

Lunar Carbon Production

2011-08-28T02:48:41Z

205.208.203.59: /* Direct CO2 Electrolysis */

== Introduction ==
Lunar [[carbon]] is found in trace amounts in the lunar regolith, where it can be extracted by heating (see [[Volatiles]]). This process results in a number of carbon compounds, chiefly carbon monoxide ([[Carbon|C]][[Oxygen|O]]), carbon dioxide ([[Carbon|C]][[Oxygen|O]]2), and methane ([[Carbon|C]][[Hydrogen|H]]4). It is desirable to produce elemental carbon from these feedstocks for production of lunar steel, as well as various other uses. In addition, processes to reduce these substances would be necessary in order to recycle carbon consumed in various industrial processes. A number of methods have been proposed for this.

== Carbon Monoxide Reduction ==
Carbon monoxide can be subjected to temperatures of around 700°C to produce carbon and carbon dioxide, a reaction that occurs in sooty chimneys.<ref>[http://www.moonminer.com/Basic-Chemistry-for-Moon-Miners.html Dietzler,Dave. "Basic Chemistry for Moon Miners" www.moonminer.com]</ref>:

2 [[Carbon Monoxide|CO]] ==> [[Carbon|C]] + [[Carbon Dioxide|CO2]]

This would recover half the carbon present in the gas. Further reduction of the carbon dioxide would be required to obtain the rest.

== Methane Reduction ==
Methane may be useful on its own as a feedstock for producing various hydrocarbons. If elemental carbon is desired, it can be subjected to thermal decomposition at high temperatures, producing [[hydrogen]] as a byproduct:
 [[Methane|CH4]] ==> [[Carbon|C]] + 2 [[Hydrogen|H]]2

Production of carbon and hydrogen in this manner has been tested with various catalysts. All had issues with carbon deposition fouling the catalyst surface. Uncatalyzed production seems to require temperatures significantly greater than 900°C <ref>Zabidi, N.A.M. and Zein, S.H.S. and Mohamed, A.R. [http://www.utp.edu.my/publications/platform/Platform%20v3n2.pdf#page=4 "Hydrogen production by catalytic decomposition of methane"] Technology Platform: Oilfield Gas Treatment and Utilization</ref>.

Uncatalyzed production has the advantage that any vessel capable of holding and heating the methane could be used as a reactor, even a simple pipe<ref>http://en.wikipedia.org/wiki/Sabatier_reaction#International_Space_Station_life_support</ref>, which could be periodically subjected to an auger to remove deposited carbon.

== Carbon Dioxide Reduction ==

=== Bosch Reaction ===

In the Bosch Reaction, carbon dioxide is reacted with hydrogen in the presence of an iron catalyst at temperatures between 530º and 730º C, producing carbon and water in a slightly exothermic process. The water is [[Water Splitting|split]], recovering the hydrogen and producing oxygen.

 [[Carbon Dioxide|CO2]] + 2 [[Hydrogen|H]]2 ==> [[Carbon|C]] + 2 [[Water|H2O]] (Bosch Reaction)
 2 [[Water|H2O]] ==> [[Oxygen|O]]2 + 2 [[Hydrogen|H]]2 ([[Water Splitting]])
 Net Reaction: [[Carbon Dioxide|CO2]] ==> [[Carbon|C]] + [[Oxygen|O]]2

This possesses the same disadvantage as low temperature methane decomposition, namely that the produced carbon builds up on the catalyst surface, reducing the efficiency. A combination of continuous mechanical scraping and large catalyst surfaces could make the reaction useable.

The bosch reaction is a subject of current research for space based carbon dioxide reduction<ref>http://people.oregonstate.edu/~atwaterj/h2o_gen.htm</ref>.

=== Sabatier Reaction ===
Another way to produce carbon from carbon dioxide is by use of the Sabatier reaction, which again involves reacting carbon dioxide with hydrogen, this time in the presence of a nickel catalyst. This process produces water and methane as reaction products:

 [[Carbon Dioxide|CO2]] + 4 [[Hydrogen|H]]2 ==> [[Methane|CH4]] + 2 [[Water|H2O]]

The water is split to recover hydrogen and oxygen, as in application of the Bosch reaction, and the methane is decomposed to carbon and hydrogen (see [[Lunar_Carbon_Production#Methane_Reduction|previous section]]).

The Sabatier Reaction is currently utilized on board the International Space Station, except that the methane produced is dumped overboard.

=== Direct CO2 Electrolysis ===
Another option is to directly electrolyze carbon dioxide<ref>[http://rtreport.ksc.nasa.gov/techreports/2002report/600%20Fluid%20Systems/609.html "Space Habitat Carbon Dioxide Electrolysis to Oxygen"]</ref>, resulting in oxygen and carbon monoxide.
 
2 [[Carbon Dioxide|CO2]] ==> 2 [[Carbon Monoxide|CO]] + [[Oxygen|O]]2

An appropriate membrane could be utilized to separate the oxygen. The carbon monoxide could be reduced to carbon and carbon dioxide (see [[Lunar Carbon Production#Carbon Monoxide Reduction|previous section]]), returning the carbon dioxide to the cell for further reduction.

A number of processes utilizing carbon monoxide as a reducing agent have been proposed for lunar use. These processes would consume carbon monoxide and produce carbon dioxide. A direct electrolysis system could be used in this case on the produced carbon dioxide, with the carbon monoxide recirculated back into the system rather than reduced further.

=== Biological Reduction ===
Carbon could be produced by heating organic material in the absence of oxygen to produce charcoal. This would require some method of removing the ash which would inevitably be present.

Growing plants specifically to produce carbon in this fashion would probably be more energy intensive than other methods. However, processing of organic waste products into carbon presents an attractive recycling mechanism, as it can be utilized on the non-edible parts of food plants and even human feces. This process would most likely be carried out in conjunction with other carbon production methods, as the human population would need to be quite high for it to supply all the carbon.

== References ==

<references/>

Lunar Carbon Production

2011-08-28T02:47:01Z

205.208.203.59: /* Carbon Monoxide Reduction */

== Introduction ==
Lunar [[carbon]] is found in trace amounts in the lunar regolith, where it can be extracted by heating (see [[Volatiles]]). This process results in a number of carbon compounds, chiefly carbon monoxide ([[Carbon|C]][[Oxygen|O]]), carbon dioxide ([[Carbon|C]][[Oxygen|O]]2), and methane ([[Carbon|C]][[Hydrogen|H]]4). It is desirable to produce elemental carbon from these feedstocks for production of lunar steel, as well as various other uses. In addition, processes to reduce these substances would be necessary in order to recycle carbon consumed in various industrial processes. A number of methods have been proposed for this.

== Carbon Monoxide Reduction ==
Carbon monoxide can be subjected to temperatures of around 700°C to produce carbon and carbon dioxide, a reaction that occurs in sooty chimneys.<ref>[http://www.moonminer.com/Basic-Chemistry-for-Moon-Miners.html Dietzler,Dave. "Basic Chemistry for Moon Miners" www.moonminer.com]</ref>:

2 [[Carbon Monoxide|CO]] ==> [[Carbon|C]] + [[Carbon Dioxide|CO2]]

This would recover half the carbon present in the gas. Further reduction of the carbon dioxide would be required to obtain the rest.

== Methane Reduction ==
Methane may be useful on its own as a feedstock for producing various hydrocarbons. If elemental carbon is desired, it can be subjected to thermal decomposition at high temperatures, producing [[hydrogen]] as a byproduct:
 [[Methane|CH4]] ==> [[Carbon|C]] + 2 [[Hydrogen|H]]2

Production of carbon and hydrogen in this manner has been tested with various catalysts. All had issues with carbon deposition fouling the catalyst surface. Uncatalyzed production seems to require temperatures significantly greater than 900°C <ref>Zabidi, N.A.M. and Zein, S.H.S. and Mohamed, A.R. [http://www.utp.edu.my/publications/platform/Platform%20v3n2.pdf#page=4 "Hydrogen production by catalytic decomposition of methane"] Technology Platform: Oilfield Gas Treatment and Utilization</ref>.

Uncatalyzed production has the advantage that any vessel capable of holding and heating the methane could be used as a reactor, even a simple pipe<ref>http://en.wikipedia.org/wiki/Sabatier_reaction#International_Space_Station_life_support</ref>, which could be periodically subjected to an auger to remove deposited carbon.

== Carbon Dioxide Reduction ==

=== Bosch Reaction ===

In the Bosch Reaction, carbon dioxide is reacted with hydrogen in the presence of an iron catalyst at temperatures between 530º and 730º C, producing carbon and water in a slightly exothermic process. The water is [[Water Splitting|split]], recovering the hydrogen and producing oxygen.

 [[Carbon Dioxide|CO2]] + 2 [[Hydrogen|H]]2 ==> [[Carbon|C]] + 2 [[Water|H2O]] (Bosch Reaction)
 2 [[Water|H2O]] ==> [[Oxygen|O]]2 + 2 [[Hydrogen|H]]2 ([[Water Splitting]])
 Net Reaction: [[Carbon Dioxide|CO2]] ==> [[Carbon|C]] + [[Oxygen|O]]2

This possesses the same disadvantage as low temperature methane decomposition, namely that the produced carbon builds up on the catalyst surface, reducing the efficiency. A combination of continuous mechanical scraping and large catalyst surfaces could make the reaction useable.

The bosch reaction is a subject of current research for space based carbon dioxide reduction<ref>http://people.oregonstate.edu/~atwaterj/h2o_gen.htm</ref>.

=== Sabatier Reaction ===
Another way to produce carbon from carbon dioxide is by use of the Sabatier reaction, which again involves reacting carbon dioxide with hydrogen, this time in the presence of a nickel catalyst. This process produces water and methane as reaction products:

 [[Carbon Dioxide|CO2]] + 4 [[Hydrogen|H]]2 ==> [[Methane|CH4]] + 2 [[Water|H2O]]

The water is split to recover hydrogen and oxygen, as in application of the Bosch reaction, and the methane is decomposed to carbon and hydrogen (see [[Lunar_Carbon_Production#Methane_Reduction|previous section]]).

The Sabatier Reaction is currently utilized on board the International Space Station, except that the methane produced is dumped overboard.

=== Direct CO2 Electrolysis ===
Another option is to directly electrolyze carbon dioxide<ref>http://rtreport.ksc.nasa.gov/techreports/2002report/600%20Fluid%20Systems/609.html</ref>, resulting in oxygen and carbon monoxide.
 
2 [[Carbon Dioxide|CO2]] ==> 2 [[Carbon Monoxide|CO]] + [[Oxygen|O]]2

An appropriate membrane could be utilized to separate the oxygen. The carbon monoxide could be reduced to carbon and carbon dioxide (see [[Lunar Carbon Production#Carbon Monoxide Reduction|previous section]]), returning the carbon dioxide to the cell for further reduction.

A number of processes utilizing carbon monoxide as a reducing agent have been proposed for lunar use. These processes would consume carbon monoxide and produce carbon dioxide. A direct electrolysis system could be used in this case on the produced carbon dioxide, with the carbon monoxide recirculated back into the system rather than reduced further.

=== Biological Reduction ===
Carbon could be produced by heating organic material in the absence of oxygen to produce charcoal. This would require some method of removing the ash which would inevitably be present.

Growing plants specifically to produce carbon in this fashion would probably be more energy intensive than other methods. However, processing of organic waste products into carbon presents an attractive recycling mechanism, as it can be utilized on the non-edible parts of food plants and even human feces. This process would most likely be carried out in conjunction with other carbon production methods, as the human population would need to be quite high for it to supply all the carbon.

== References ==

<references/>

Sulfur

2011-08-28T02:38:15Z

205.208.203.59: reformatted reference

{{Element |
name=Sulfur |
symbol=S |
available=good |
need= |
number=16 |
mass=32.066 |
group=16 |
period=3 |
phase=Solid |
series=Non-metals |
density=(alpha) 2.07 g/cm3 
(beta) 1.96 g/cm3 
(gamma) 1.92 g/cm3 |
melts=388.36K, 115.21°C, 239.38°F |
boils=717.8K, 444.6°C, 832.3°F |
isotopes=32 33 34 36 |
prior=[[Phosphorus|P]] |
next=[[Chlorine|Cl]] |
above=[[Oxygen|O]] |
aprior=[[Nitrogen|N]] |
anext=[[Fluorine|F]] |
below=[[Selenium|Se]] |
bprior=[[Arsenic|As]] |
bnext=[[Bromine|Br]] |
radius=100 |
bohr=88 |
covalent=102 |
vdwr=180 |
irad=(-2) 184 |
ipot=10.36 |
econfig=1s2 2s2 2p6 3s2 3p4 |
eshell=2, 8, 6 |
enega=2.58 |
eaffin=2.08 |
oxstat=+/-2, 4, '''6''' |
magn=? |
cryst=Orthorhombic |
}}
'''Sulfur''' is a Non-metal in group 16.
It has a Orthorhombic crystalline structure.
This element has 4 stable isotopes: 32, 33, 34, and 36.
 

Sulfur is availible in lunar soil in significant quantities, with some mare soils containing as much as .27% by weight, and can be obtained by roasting the soil at high temperatures. Several uses have been proposed for lunar sulfur, including [[In-Situ Propellant Production#Sulfur|rocket propellant]], production of sulfuric acid for industrial processes, and the manufacture of sealants<ref>[http://www.nss.org/settlement/moon/library/LB2-509-UsesOfLunarSulfur.pdf V. T. Vaniman, D. R. Pettit, G. Heiken. "Uses of Lunar Sulfur" Los Alamos National Laboratory, 1988]</ref>.

== References ==
<references/>

[[Category:Solids]]
[[Category:Non-metals ]]

Iron

2011-08-20T20:42:50Z

205.208.203.59: Added lunar use description, removed autostub tag

{{Element |
name=Iron |
symbol=Fe |
available=abundant |
need=essential |
number=26 |
mass=55.845 |
group=8 |
period=4 |
phase=Solid |
series=Transition Metals |
density=7.86 g/cm3 |
melts=1811K, 1538°C, 2800°F |
boils=3134K, 2861°C, 5182°F |
isotopes=54 56 57 58 |
prior=[[Manganese|Mn]] |
next=[[Cobalt|Co]] |
above=N/A |
aprior=N/A |
anext=N/A |
below=[[Ruthenium|Ru]] |
bprior=[[Technetium|Tc]] |
bnext=[[Rhodium|Rh]] |
radius=140 |
bohr=156 |
covalent=125 |
vdwr= |
irad=(+3) 55 |
ipot=7.90 |
econfig=1s2 2s2 2p6 3s2 3p6 3d6 4s2 |
eshell=2, 8, 14, 2 |
enega=1.83 |
eaffin=0.15 |
oxstat=2, '''3''' |
magn=Ferromagnetic |
cryst=Body centered cubic |
}}
'''Iron''' is a Transition Metal in group 8.
It has a Body centered cubic crystalline structure.
This element has 4 stable isotopes: 54, 56, 57, and 58.
 

== Application to Lunar Colonization ==

== Lunar Iron Use/Production ==
Lunar iron is present both in metallic form and as oxides. Metallic iron is found virtually everywhere on the moon, alloyed with nickel in tiny particles dispersed in the regolith, the remnants of pulverized nickel-iron meteorites. Iron oxides are found predominately on the [[maria]], where they can make up nearly 15% of the regolith by weight. Due to this abundance of both free iron and iron oxides, as well as the fact that iron oxides require less energy to reduce than any other oxide found in the lunar surface, iron is considered to be the easiest metal to obtain on Luna.

Due to this ease of acquirement, lunar iron could become a workhorse metal for lunar construction. Iron could be alloyed with [[carbon]] extracted from the lunar regolith to produce steel. Other important alloying elements include [[titanium]], [[chromium]], [[nickel]], and [[manganese]], all of which are available from lunar sources.

Metalic iron is strongly attracted to magnetic fields, and can be easily [[Iron Beneficiation|separated from the lunar regolith]] by magnetic processes. Many iron oxides can also be extracted from the regolith using magnetic separation, including [[Ilmenite]](Fe[[Titanium|Ti]][[Oxygen|O]]3), hematite (Fe2[[Oxygen|O]]3), and magnetite (Fe[[Oxygen|O]].Fe2[[Oxygen|O]]3). These oxides generally have much weaker attraction to magnetic fields than metallic iron, enabling separation of the two after gathering.

==Related Article==
*[[Iron Beneficiation]]
*[[Lunar Titanium Production]]
*[[Ilmenite Reduction]]

==External Links==
*[http://lunar.arc.nasa.gov/results/gamres.htm Lunar Prospector: Gamma Ray Spectrometer Results]

[[Category:Ferromagnetic Elements]]
[[Category:Solids]]
[[Category:Transition Metals ]]
[[Category:Critical and Essential Elements]]
[[Category:Abundant Elements]]

Lunar Titanium Production

2011-08-20T20:19:11Z

205.208.203.59: /* Terrestrial Production */ added link to carbon monoxide reduction techniques

== Introduction ==

The main source of Lunar [[Titanium]] is in the form of [[Ilmenite]] ([[Iron|Fe]][[Titanium|Ti]][[Oxygen|O]]3). This material is found abundantly on the lunar surface, especially on the Maria. Being weakly magnetic, Ilmenite could be concentrated from the lunar regolith in a magnetic separator (a multistage device may be necessary due to other magnetic minerals present). There are several ways Titanium could be produced in a Lunar environment.

== Terrestrial Production ==

On earth, Ilmenite is subjected to the Chloride Process<ref>http://en.wikipedia.org/wiki/Chloride_process</ref>, where it is reacted with [[carbon]] and [[chlorine]] to produce titanium and iron chlorides according to the formula:

:2 [[Ilmenite|FeTiO3]] + 7 [[Cl]]2 + 6 [[C]] → 2 [[Ti]][[Cl]]4 + 2 [[Fe]][[Cl]]3 + 6 [[Carbon Monoxide | CO]]

The titanium tetrachloride is separated from the other reaction products by distillation. Once separated, it is reacted with liquid [[magnesium]] in the Kroll process<ref>http://en.wikipedia.org/wiki/Kroll_process</ref>, producing [[titanium]] metal and [[magnesium]] chloride:

:[[Ti]][[Cl]]4 + 2[[Mg]] → Ti + 2 [[Mg]][[Cl]]2

The resulting sponge of [[titanium]] metal is then either crushed and washed or subjected to vacuum distillation to remove the magnesium chloride, and then melted and further refined to the desired purity.

It is possible to adapt this process to a lunar environment, though it presents some challenges. The [[chlorine]] and [[carbon]] required in the process would have to be stringently recycled, as they are rare (and hence likely to be quite expensive) in a lunar environment. The [[magnesium]] and [[iron]] chlorides would need to be electrolyzed to their respective metals, recovering the [[chlorine]]. Recovering the [[carbon]] and [[oxygen]] from the [[carbon monoxide]] is a bit less straightforward, [[Lunar Carbon Production|though several methods exist]].

== Hydrogen Reduction ==
see also: [[Ilmenite_Reduction#Hydrogen Reduction|Hydrogen Reduction]]

Ilmenite could be reacted with [[hydrogen]], producing [[iron]] and [[rutile|titanium dioxide]]. The iron could then be separated by [[Carbonyl process|carbonyl extraction]], distillation, or by grinding and removing the iron particles with a magnet. The [[rutile|titanium dioxide]] would then be refined by other means.

== FFC Cambridge Process ==
Main Article: [[FFC Cambridge Process#Iron/Titanium Production from Ilmenite|FFC Cambridge Process]].

The FFC Cambridge Process is a method of performing electrolysis on solid metal oxides. The oxide to be reduced is formed into a cathode and subjected to electrolysis in a molten calcium chloride bath. Oxygen is stripped off and bubbles off at the anode, leaving behind a metallic sponge.

The FFC Cambridge process could be used on the titanium dioxide produced from hydrogen reduction of Ilmenite, or the [[Ilmenite]] could be directly reduced, producing an [[Iron]]-[[Titanium]] alloy, which is then separated by [[Carbonyl process|carbonyl extraction]] or distillation.

== References ==
<references/>

[[Category:Industrial Production]]

Lunar Carbon Production

2011-08-20T20:14:30Z

205.208.203.59: /* Methane Reduction */

== Introduction ==
Lunar [[carbon]] is found in trace amounts in the lunar regolith, where it can be extracted by heating (see [[Volatiles]]). This process results in a number of carbon compounds, chiefly carbon monoxide ([[Carbon|C]][[Oxygen|O]]), carbon dioxide ([[Carbon|C]][[Oxygen|O]]2), and methane ([[Carbon|C]][[Hydrogen|H]]4). It is desirable to produce elemental carbon from these feedstocks for production of lunar steel, as well as various other uses. In addition, processes to reduce these substances to elemental carbon would be necessary in order to recycle carbon consumed in various industrial processes. A number of methods have been proposed for this.

== Carbon Monoxide Reduction ==
Carbon monoxide can be subjected to temperatures of around 700°C to produce carbon and carbon dioxide, a reaction that occurs in sooty chimneys.<ref>http://www.moonminer.com/Basic-Chemistry-for-Moon-Miners.html</ref>:

2 [[Carbon Monoxide|CO]] ==> [[Carbon|C]] + [[Carbon Dioxide|CO2]]

This would recover half the carbon present in the gas. Further reduction of the carbon dioxide would be required to obtain the rest.

== Methane Reduction ==
Methane may be useful on its own as a feedstock for producing various hydrocarbons. If elemental carbon is desired, it can be subjected to thermal decomposition at high temperatures, producing [[hydrogen]] as a byproduct:
 [[Methane|CH4]] ==> [[Carbon|C]] + 2 [[Hydrogen|H]]2

Production of carbon and hydrogen in this manner has been tested with various catalysts. All had issues with carbon deposition fouling the catalyst surface. Uncatalyzed production seems to require temperatures significantly greater than 900°C <ref>Zabidi, N.A.M. and Zein, S.H.S. and Mohamed, A.R. [http://www.utp.edu.my/publications/platform/Platform%20v3n2.pdf#page=4 "Hydrogen production by catalytic decomposition of methane"] Technology Platform: Oilfield Gas Treatment and Utilization</ref>.

Uncatalyzed production has the advantage that any vessel capable of holding and heating the methane could be used as a reactor, even a simple pipe<ref>http://en.wikipedia.org/wiki/Sabatier_reaction#International_Space_Station_life_support</ref>, which could be periodically subjected to an auger to remove deposited carbon.

== Carbon Dioxide Reduction ==

=== Bosch Reaction ===

In the Bosch Reaction, carbon dioxide is reacted with hydrogen in the presence of an iron catalyst at temperatures between 530º and 730º C, producing carbon and water in a slightly exothermic process. The water is [[Water Splitting|split]], recovering the hydrogen and producing oxygen.

 [[Carbon Dioxide|CO2]] + 2 [[Hydrogen|H]]2 ==> [[Carbon|C]] + 2 [[Water|H2O]] (Bosch Reaction)
 2 [[Water|H2O]] ==> [[Oxygen|O]]2 + 2 [[Hydrogen|H]]2 ([[Water Splitting]])
 Net Reaction: [[Carbon Dioxide|CO2]] ==> [[Carbon|C]] + [[Oxygen|O]]2

This possesses the same disadvantage as low temperature methane decomposition, namely that the produced carbon builds up on the catalyst surface, reducing the efficiency. A combination of continuous mechanical scraping and large catalyst surfaces could make the reaction useable.

The bosch reaction is a subject of current research for space based carbon dioxide reduction<ref>http://people.oregonstate.edu/~atwaterj/h2o_gen.htm</ref>

=== Sabatier Reaction ===
Another way to produce carbon from carbon dioxide is by use of the Sabatier reaction, which again involves reacting carbon dioxide with hydrogen, this time in the presence of a nickel catalyst. This process produces water and methane as reaction products:

 [[Carbon Dioxide|CO2]] + 4 [[Hydrogen|H]]2 ==> [[Methane|CH4]] + 2 [[Water|H2O]]

The water is split to recover hydrogen and oxygen, as in application of the Bosch reaction, and the methane is decomposed to carbon and hydrogen (see previous section).

This Sabatier Reaction is currently utilized on board the International Space Station, except that the methane produced is dumped overboard.

=== Direct Co2 Electrolysis ===
Another option is to directly electrolyze carbon dioxide<ref>http://rtreport.ksc.nasa.gov/techreports/2002report/600%20Fluid%20Systems/609.html</ref>, resulting in oxygen and carbon monoxide.
 
2 [[Carbon Dioxide|CO2]] ==> 2 [[Carbon Monoxide|CO]] + [[Oxygen|O]]2

An appropriate membrane could be utilized to separate the oxygen, and the carbon monoxide could be reduced to carbon and carbon dioxide (see previous section). The carbon dioxide would be returned to the cell to be electrolyzed again.

=== Biological Reduction ===
Carbon could be produced from carbon dioxide by plant growth, followed by heating in the absence of oxygen to produce charcoal. This method is especially attractive if food plants are used, utilizing the non-edible portions of said plants for carbon production. This process would result in a fair amount of ash present in the resulting carbon, and would require more input energy than the other processes mentioned, though possibly at a lower technological and maintenance level. The demand for food products would probably need to be quite high compared to the demand for elemental carbon for this approach to be used as a primary carbon source.

== References ==

<references/>

Lunar Carbon Production

2011-08-20T20:13:47Z

205.208.203.59: /* Carbon Monoxide Reduction */

== Introduction ==
Lunar [[carbon]] is found in trace amounts in the lunar regolith, where it can be extracted by heating (see [[Volatiles]]). This process results in a number of carbon compounds, chiefly carbon monoxide ([[Carbon|C]][[Oxygen|O]]), carbon dioxide ([[Carbon|C]][[Oxygen|O]]2), and methane ([[Carbon|C]][[Hydrogen|H]]4). It is desirable to produce elemental carbon from these feedstocks for production of lunar steel, as well as various other uses. In addition, processes to reduce these substances to elemental carbon would be necessary in order to recycle carbon consumed in various industrial processes. A number of methods have been proposed for this.

== Carbon Monoxide Reduction ==
Carbon monoxide can be subjected to temperatures of around 700°C to produce carbon and carbon dioxide, a reaction that occurs in sooty chimneys.<ref>http://www.moonminer.com/Basic-Chemistry-for-Moon-Miners.html</ref>:

2 [[Carbon Monoxide|CO]] ==> [[Carbon|C]] + [[Carbon Dioxide|CO2]]

This would recover half the carbon present in the gas. Further reduction of the carbon dioxide would be required to obtain the rest.

== Methane Reduction ==
Methane may be useful on its own as a feedstock for producing various hydrocarbons. If elemental carbon is desired, it can be subjected to thermal decomposition at high temperatures, producing [[hydrogen]] as a byproduct:
[[Methane|CH4]] ==> [[Carbon|C]] + 2 [[Hydrogen|H]]2

Production of carbon and hydrogen in this manner has been tested with various catalysts. All had issues with carbon deposition fouling the catalyst surface. Uncatalyzed production seems to require temperatures significantly greater than 900°C <ref>Zabidi, N.A.M. and Zein, S.H.S. and Mohamed, A.R. [http://www.utp.edu.my/publications/platform/Platform%20v3n2.pdf#page=4 "Hydrogen production by catalytic decomposition of methane"] Technology Platform: Oilfield Gas Treatment and Utilization</ref>.

Uncatalyzed production has the advantage that any vessel capable of holding and heating the methane could be used as a reactor, even a simple pipe<ref>http://en.wikipedia.org/wiki/Sabatier_reaction#International_Space_Station_life_support</ref>, which could be periodically subjected to an auger to remove deposited carbon.

== Carbon Dioxide Reduction ==

=== Bosch Reaction ===

In the Bosch Reaction, carbon dioxide is reacted with hydrogen in the presence of an iron catalyst at temperatures between 530º and 730º C, producing carbon and water in a slightly exothermic process. The water is [[Water Splitting|split]], recovering the hydrogen and producing oxygen.

 [[Carbon Dioxide|CO2]] + 2 [[Hydrogen|H]]2 ==> [[Carbon|C]] + 2 [[Water|H2O]] (Bosch Reaction)
 2 [[Water|H2O]] ==> [[Oxygen|O]]2 + 2 [[Hydrogen|H]]2 ([[Water Splitting]])
 Net Reaction: [[Carbon Dioxide|CO2]] ==> [[Carbon|C]] + [[Oxygen|O]]2

This possesses the same disadvantage as low temperature methane decomposition, namely that the produced carbon builds up on the catalyst surface, reducing the efficiency. A combination of continuous mechanical scraping and large catalyst surfaces could make the reaction useable.

The bosch reaction is a subject of current research for space based carbon dioxide reduction<ref>http://people.oregonstate.edu/~atwaterj/h2o_gen.htm</ref>

=== Sabatier Reaction ===
Another way to produce carbon from carbon dioxide is by use of the Sabatier reaction, which again involves reacting carbon dioxide with hydrogen, this time in the presence of a nickel catalyst. This process produces water and methane as reaction products:

 [[Carbon Dioxide|CO2]] + 4 [[Hydrogen|H]]2 ==> [[Methane|CH4]] + 2 [[Water|H2O]]

The water is split to recover hydrogen and oxygen, as in application of the Bosch reaction, and the methane is decomposed to carbon and hydrogen (see previous section).

This Sabatier Reaction is currently utilized on board the International Space Station, except that the methane produced is dumped overboard.

=== Direct Co2 Electrolysis ===
Another option is to directly electrolyze carbon dioxide<ref>http://rtreport.ksc.nasa.gov/techreports/2002report/600%20Fluid%20Systems/609.html</ref>, resulting in oxygen and carbon monoxide.
 
2 [[Carbon Dioxide|CO2]] ==> 2 [[Carbon Monoxide|CO]] + [[Oxygen|O]]2

An appropriate membrane could be utilized to separate the oxygen, and the carbon monoxide could be reduced to carbon and carbon dioxide (see previous section). The carbon dioxide would be returned to the cell to be electrolyzed again.

=== Biological Reduction ===
Carbon could be produced from carbon dioxide by plant growth, followed by heating in the absence of oxygen to produce charcoal. This method is especially attractive if food plants are used, utilizing the non-edible portions of said plants for carbon production. This process would result in a fair amount of ash present in the resulting carbon, and would require more input energy than the other processes mentioned, though possibly at a lower technological and maintenance level. The demand for food products would probably need to be quite high compared to the demand for elemental carbon for this approach to be used as a primary carbon source.

== References ==

<references/>

Hydrogen

2011-08-17T02:23:42Z

205.208.203.59: /* Related Pages */ added water splitting link

{{Element |
name=Hydrogen |
symbol=H |
available=trace |
need=critical |
number=1 |
mass=1.00794 |
group=1 |
period=1 |
phase=Gas |
series=Non-metals |
density=0.08988 g/L |
melts=14.175K -258.975°C -434°F |
boils=20.418K -252.732°C -422.918°F |
isotopes=1 2 |
prior=N/A |
next=[[Helium|He]] |
above=N/A |
aprior=N/A |
anext=N/A |
below=[[Lithium|Li]] |
bprior=N/A |
bnext=[[Beryllium|Be]] |
radius=25 |
bohr=53 |
covalent=37 |
vdwr=120 |
irad=- |
ipot=13.60 |
econfig=1s1 |
eshell=1 |
enega=2.2 |
eaffin= |
oxstat=1 |
magn= |
cryst=Hexagonal |
}}

== Introduction ==

'''Hydrogen''' is a Non-metal in group 1.
It has a Hexagonal crystalline structure.
This element has two stable isotopes: 1 and 2.

Natural Isotopes
*1H (single electron, single proton)
*2H Deuterium (single electron, single proton, single neutron)

Synthetic Isotopes
*3H Tritium (single electron, single proton, two neutrons)
**12.33 year half life. Undergoes Beta Decay to become [[Helium 3]]([[He3]] or [[He3|3He]])
*4H
**Undergoes immediate Neutron Decay to become Tritium(3H)

'''Hydrogen''' is the simplest, lightest, and first element formed after the big bang. It is the most common element, making up approx 90% of the universe by weight.

== Applications to Lunar Colonization ==

Hydrogen has many proposed applications in a lunar environment. These include [[In-Situ_Propellant_Production#Hydrogen|rocket fuel]], energy storage, [[Ilmenite reduction#Hydrogen Reduction|reduction of metal]] and carbon oxides, and many other uses. Hydrogen production and recycling could become major functions of a lunar outpost.

Deuterium could be used as as fuel in nuclear fusion reactions, although the percentage of deuterium in lunar hydrogen is significantly less than on earth, which could make its production difficult.

== Lunar Hydrogen Production ==

The moon is significantly depleted of hydrogen compared to the earth. On earth, hydrogen is most commonly found combined with [[oxygen]] in the form of [[water]] (H2O). The Moon is much smaller than Earth, and its gravity is not strong enough to retain a gaseous atmosphere permanently. In addition, the moon lacks a magnetic field, allowing the solar wind to directly interact with its surface, constantly stripping away any atmosphere it manages to cling to. As a result, most of the volatiles of the Moon, including hydrogen, have long since evaporated and escaped into space.

However, hydrogen is constantly implanted into the lunar surface by the same solar wind that strips it away. As such, hydrogen is found in the lunar regolith in concentrations in the range of 40-50 parts per million. Methods of extracting hydrogen (along with other deposited volatiles) from the lunar surface have been proposed, usually involving heating the regolith until outgassing occurs (see [[Volatiles]]).

In addition, more concentrated reserves of hydrogen exist in deep craters at the Lunar poles in the form of water ice. These craters are permanently shielded from the sun, and as such are quite cold (< 100 K). These areas act as cold traps for any volatiles that happen to pass into them, whether from comet impact or ongoing creation via the solar wind. As a result, they contain significant amounts of water, as well as other volatiles.

Mining these polar deposits poses the problem of designing equipment capable of operating in extremely cold temperatures. In addition, the exact amount of resources available in these craters is not known, being a subject of some debate.

== Related Pages ==
*[[Volatiles]]
*[[Water Splitting]]

==External Links==
[http://environmentalchemistry.com/yogi/periodic/H.html Environmental Chemistry: Hydrogen] 
[http://www.webelements.com/webelements/elements/text/H/key.html WebElements: Hydrogen] 

[[Category:Gases]]
[[Category:Non-metals ]]
[[Category:Critical and Essential Elements]]

Water Splitting

2011-08-17T02:21:58Z

205.208.203.59: /* Introduction */ rewording

== Introduction ==

Water splitting refers to methods by which [[Water]] ([[Hydrogen|H]]2[[Oxygen|O]]) is separated into [[Hydrogen]] and [[Oxygen]]. [[Hydrogen]] is proposed as a reactant in a large number of lunar applications, including metal oxide and carbon oxide reduction, which would produce water as a byproduct. Splitting said water to recover the hydrogen during these applications is expected to be an important component of their functions.

== Electrolysis ==

One of the simplest ways to reduce water to hydrogen and oxygen is by electrolysis. In the simplest implementation, two electrodes are placed in water containing enough dissolved salts to allow for electrical conduction, and a current is run between the electrodes. This action causes the water molecules to split into hydrogen and oxygen. The oxygen collects at the anode (positively charged or ground connection), and the hydrogen collects at the cathode (the negative connection, where the current enters), where they are pumped out.

This process can be improved in efficiency by careful choice of electrode material and design. Also, performing electrolysis on water at very high temperatures results in less electricity being used, as a portion of the required energy is provided as heat. This approach is currently being researched.

Efficiencies vary widely depending on the exact setup, but efficiencies in the range of 50%-80% appear to be feasible. These efficiencies reflect the conversion of electrical energy into chemical energy, not counting the efficiency of producing the electricity.

== Sulfur Iodine Cycle ==

Another proposed method of water splitting is the the Sulfur Iodine Cycle. In this process, water is mixed with iodine and sulfur dioxide, resulting in hydrogen iodide and sulfuric acid:

2 [[Water|H2O]] + [[Sulfur|S]][[Oxygen|O]]2 + [[Iodine|I]]2 ==> 2 [[Hydrogen|H]][[Iodine|I]] + [[Sulfuric Acid|H2SO4]] (120°C)

The hydrogen iodide evaporates out and is subjected to more intense heat treatment, where it breaks down into hydrogen and iodine:

2 HI ==> [[Hydrogen|H]]2 + [[Iodine|I]]2 (450°C)

the result is cooled to separate the iodine and send it back to the first step, and the hydrogen is piped out.

Meanwhile, the sulfuric acid produced in the first step is subjected to very high temperatures, producing oxygen, water, and sulfur dioxide:

2 [[Sulfuric Acid|H2SO4]] ==> [[Oxygen|O]]2 + 2 [[Water|H2O]] + 2 [[Sulfur|S]][[Oxygen|O]]2 (850°C)

The water and sulfur dioxide are condensed out and sent back to the first step, and the oxygen is piped out.

This process has the disadvantage of being significantly more complex when compared with electrolysis, as well as requiring careful selection of apparatus materials due to the high temperature and corrosive environment. However, the sulfur iodine cycle has a high efficiency of around 50%. More importantly, this efficiency represents the conversion of heat to chemical energy directly, no electricity is needed.

If direct heat sources are available in the temperatures needed (from solar concentrators or a nuclear reactor for example), producing hydrogen with the sulfur iodine cycle has potential to be significantly more efficient than electrolysis, as electrolysis efficiency ends up being in the 30-45% range once losses in power generation are included. If, however, electricity is the default source of energy available (from [[Solar Power Satellites]] or a lunar electrical grid), electrolysis would likely be the method of choice, as it is simpler and has roughly the same (or higher) efficiencies when using electricity.

== External Links ==
*[http://en.wikipedia.org/wiki/Electrolysis_of_water Electrolysis of Water on Wikipedia]
*[http://en.wikipedia.org/wiki/Sulfur_iodine_cycle Sulfur Iodine Cycle on Wikipedia]

[[Category:Industrial Production]]

Oxygen

2011-08-17T01:54:16Z

205.208.203.59: Removed stub tag, reworded

{{Element |
name=Oxygen |
symbol=O |
available=abundant |
need=critical |
number=8 |
mass=15.9994 |
group=16 |
period=2 |
phase=Gas |
series=Non-metals |
density=1.429 g/L |
melts=54.36K, -218.79°C, -361.82°F |
boils=0.20K, -182.95°C, -297.31°F |
isotopes=16 17 18 |
prior=[[Nitrogen|N]] |
next=[[Fluorine|F]] |
above=N/A |
aprior=N/A |
anext=N/A |
below=[[Sulfur|S]] |
bprior=[[Phosphorus|P]] |
bnext=[[Chlorine|Cl]] |
radius=60 |
bohr=48 |
covalent=73 |
vdwr=152 |
irad=(-2) 140 |
ipot=13.62 |
econfig=1s2 2s2 2p4 |
eshell=2, 6 |
enega=3.44 |
eaffin=1.46 |
oxstat=-2 |
magn=Paramagnetic |
cryst=Cubic |
}}
'''Oxygen''' is a Non-metal in group 16.
It has a Cubic crystalline structure.
This element has 3 stable isotopes: 16, 17, and 18.
 

==Lunar Production and Use==
Oxygen production from lunar sources (sometimes referred to as '''LUNOX''') is a critical element of any plan involving long term human presence on Luna. Oxygen is required for both life support and rocket fuel, and as such would be needed in large quantities. Lunar Oxygen production is one category of [[In Situ Resource Utilization]](''ISRU'').

Oxygen makes up about 45% of the moons crust by weight, and virtually every substance on the moons surface is an oxide. As such, production of nearly anything other than oxygen from lunar resources will produce substantial amounts of oxygen as a byproduct. In addition, free (not bound chemically with other elements) oxygen exists in the lunar soil, albeit in small quantities.

Processes which produce oxygen from lunar sources include:

*Aluminum reduction
*Carbothermal reduction
*[[Volatiles|Volatile Extraction]]
*[[Fluorine reaction]]
*[[Magma electrolysis]]
*[[Ilmenite Reduction]]
*Methane reduction
*hydrogen reduction of glass
*sulfuric acid dissolution/electrolysis
*ion sputtering.

== Related Pages ==
*[[In Situ Resource Utilization]]

==External Links==

*[http://nss.org/settlement/nasa/spaceresvol3/plsoom1.htm lunar oxygen process sequence discussion from Knudson and Gibson (1989)] (note: a good summary of approaches, but somewhat out of date)
*[http://www.moonminer.com/Moondust_index.html Lunar processing links from David Dietzler]
*[http://www.magicdragon.com/ComputerFutures/SpacePublications/llox-footnoted.html LLOX automated production summary (1990)]
* ''The Moon: Resources, Future Development, and Colonization'' by David Schrunk, Burton Sharpe, Bonnie Cooper and Madhu Thangavelu - appendix E covers a wide range of oxygen extraction methods.
 

==References==

One reference useful as an overview is The Moon: Resources, Future Development, and Colonization, by David Schrunk, Burton Sharpe, Bonnie Cooper and Madhu Thangavelu.

From review by Arthur Smith on ADB: "In particular Appendix E's coverage of oxygen extraction is extremely thorough, and the authors, while finding it somewhat difficult to directly compare techniques, find 4 of the approaches worthy of considerable further research: hydrogen reduction of glass, magma electrolysis, sulfuric acid dissolution/electrolysis, and ion sputtering."

[[Category:Paramagnetic Elements]]
[[Category:Gases]]
[[Category:Non-metals]]
[[Category:Critical and Essential Elements]]
[[Category:Abundant Elements]]

Ilmenite Reduction

2011-08-17T01:42:06Z

205.208.203.59: /* Hydrogen Reduction */ changed link text slightly

== Introduction ==
[[Reduction|Reducing]] [[ilmenite]] (FeTiO3) to produce [[oxygen]], [[iron]], and [[titanium]] in a lunar context has produced a number of proposals, many of them specifically aimed at oxygen production. Ilmenite is attractive for this purpose as it requires less energy to split oxygen from than many other oxides found on the lunar surface.
==Hydrogen Reduction==
[[image:ilmen_reduced.GIF|thumb|Lunar Ilmenite reduced at 1050°C by hydrogen for 3 hrs]]
[[Hydrogen]] reduction is one method currently being tested by many Universities. Products of hydrogen reduction are free [[iron]], [[rutile|titanium dioxide (TiO2)]], and [[water]], which is [[Water Splitting|split]] to recover the hydrogen and produce [[oxygen]].

The basic process is to separate ilmenite from lunar soil, crush it to a fine powder to maximize the surface area, and then heat it in an enclosed reaction vessel in the presence of hydrogen gas. The steam produced in the reaction is then condensed and [[Water Splitting|split]] to produce oxygen and recover the hydrogen.

This process is best utilized if the plant is sited in a location in which ilmenite composes a high fraction of the soil.

The reaction sequence is:
*''Reduction'': FeTiO3+H2 ---->Fe+TiO2+H2O
*''Water Splitting'': 2H2O ---->2 H2+ O2
*''Net Reaction'': 2FeTiO3----> 2Fe+2TiO2+ O2

The iron produced in the process could be separated out by [[Carbonyl process| carbonyl extraction]], or by grinding the result again and using a magnet. The [[rutile|titanium dioxide]] could also be further [[Lunar Titanium Production|reduced to produce metallic titanium and additional oxygen]].

==Carbothermal Reduction==

Oxygen can be retrieved from [[Ilmenite|Ilmenite (FeTiO3)]] and [[Rutile|Rutile (TiO2)]] by means of carbothermal reduction. In [http://www.mtec.or.th/th/seminar/msativ/pdf/CP12.pdf experiments], powdered [[carbon]] and powdered ilmenite/rutile were evenly mixed and then heated to 1500 degrees Celsius. The end products of this reaction are Oxygen and a high strength Ceramic-metal composite (Cermet) of [[iron|Iron (Fe)]] and Titanium Carbide (TiC) which has high chemical stability. The amount of reinforcing TiC ceramic in the matrix can be controlled via the amount of rutile and carbon used. While this method provides a means of retrieving all of the oxygen from ilmenite/rutile and a potential for producing reinforced, high performance and wear components and cutting tools from lunar regolith, it is at the cost of highly valuable carbon needed for biological processes. The process will also require the separation of ilmenite/rutile from regolith by some means.

Stoichiometry for this reaction:
 
''Ilmenite'': 
FeTiO3 + 4C ---->Fe + TiC + 3CO
 
''Ilmenite and Rutile'': 
FeTiO3 + nTiO2 + (4+3n)C ---->Fe + (1+n)TiC + (3+2n)CO
 Where n represents the number of TiO2 molecules

===Reduction with CO===
This reaction is based on a fluidized bed scheme which is similar to large scale proposals for Hydrogen Reduction. The product of CO reduction of Ilmenite is [[Carbon Dioxide|Carbon Dioxide (CO2)]], which must be cracked using significant energy in an endothermic electrolysis reaction to yield oxygen which can be drawn off via a ceramic membrane. See [http://www.uapress.arizona.edu/onlinebks/ResourcesNearEarthSpace/resources04.pdf this paper, page 9]. The presence of solar wind implanted carbon in the regolith (20-30ppm) will allow the recovery of additional carbon, but the presence of solar wind implanted hydrogen (hundreds of ppm) may complicate the reaction into one that involves methane (CH4). The CO reduction of ilmenite is slower than the H2 process, but by less than an order of magnitude for any given temperature.

The reaction sequence is:
 
''Reduction'': 
FeTiO3 + CO ---->Fe + TiO2 + CO2
 
''Endothermic cracking'': 
2CO2 ----> 2CO + O2
 
''Net Reaction'': 
2FeTiO3 + 2CO ---->2Fe + 2TiO2 + 2CO + O2
 

==Methane Reduction==
{| cellpadding="10" style="border-style:none;border-width:0px"
| style="border-style:dashed; border-width:1px; border-color:#36648B; background:#F0F8FF;" | '''Please note: Methane Reduction''' 
This section is a placeholder for work currently in progress. -- [[User:Jarogers2001|Jarogers2001]] 22:59, 31 May 2008 (UTC)
|}
==Li or Na Reduction==
==Plasma Reduction==

== Electrolytic Reduction ==
see [[FFC Cambridge Process]]

== Related Pages ==
*[[Lunar Titanium Production]]

==External Links==
*ISRU on the Moon. by Larry Taylor [http://www.lpi.usra.edu/lunar_knowledge/LTaylor.pdf http://www.lpi.usra.edu/lunar_knowledge/LTaylor.pdf]
*Extraction Techniques-Oxygen. G. L. Kulcinski, February 18, 2004 [http://fti.neep.wisc.edu/neep533/SPRING2004/lecture13.pdf http://fti.neep.wisc.edu/neep533/SPRING2004/lecture13.pdf]
*Processing Lunar Soils for Oxygen and Other Materials. Knudsen & Gibson [http://nss.org/settlement/nasa/spaceresvol3/plsoom1.htm http://nss.org/settlement/nasa/spaceresvol3/plsoom1.htm]
*[http://ares.jsc.nasa.gov/HumanExplore/Exploration/EXLibrary/DOCS/EIC048.HTML Lunar Oxygen Production - A Maturing Technology]
*[http://www.mtec.or.th/th/seminar/msativ/pdf/CP12.pdf The Effect of TiO2 on Synthesizing Fe-TiC Composites]
*[http://www.nss.org/settlement/spaceresources/resources2.html Resources of Near-Earth Space. Univ. of Arizona Press]
 

[[Category:Air Supply]]
[[Category:Chemistry]]
[[Category:ISRU]]
[[Category:Industrial Production]]

Cobalt

2011-08-14T00:29:56Z

205.208.203.59: added Lunar Cobalt production section and link

{{Element |
name=Cobalt |
symbol=Co |
available=available |
need= |
number=27 |
mass=58.9332 |
group=9 |
period=4 |
phase=Solid |
series=Transition Metals |
density=8.90 g/cm3 |
melts=1768K, 1495°C, 2723°F |
boils=3200K, 2927°C, 5301°F |
isotopes=59 |
prior=[[Iron|Fe]] |
next=[[Nickel|Ni]] |
above=N/A |
aprior=N/A |
anext=N/A |
below=[[Rhodium|Rh]] |
bprior=[[Ruthenium|Ru]] |
bnext=[[Palladium|Pd]] |
radius=135 |
bohr=152 |
covalent=126 |
vdwr= |
irad=(+2) 65 |
ipot=7.88 |
econfig=1s2 2s2 2p6 3s2 3p6 3d7 4s2 |
eshell=2, 8, 15, 2 |
enega=1.88 |
eaffin=0.66 |
oxstat='''2''', 3 |
magn=Ferromagnetic |
cryst=Hexagonal |
}}
'''Cobalt''' is a Transition Metal in group 9.
It has a Hexagonal crystalline structure.
This element has a stable isotope of 59
 

== Lunar Cobalt Production ==
Cobalt is a minor component of [[Nickel]]-[[Iron]] meteorites, the pulverized remains of which are scattered over the lunar surface. It could be extracted as a side product during [[Iron Beneficiation|iron and nickel production from iron fines]].

{{Autostub}}
[[Category:Ferromagnetic Elements]]
[[Category:Solids]]
[[Category:Transition Metals ]]

Water

2011-08-13T05:24:50Z

205.208.203.59: /* Water and Fuel */ links

'''Water''', '''H2O''', is an ubiquitous molecule in the universe and very common in our Solar System. There is water in the atmosphere of Venus, drenching the Earth, as permafrost and polar caps on Mars, and it is the major component of several moons of the outer Solar System, as well as much of the debris farther out in the Kuiper Belt and Oort Cloud. So it came as quite a surprise in the 1960s, when samples were brought back from the Moon for the first time, that the Moon was ''anhydrous'', or without water. This was more profound than the lack of groundwater or permafrost; the water that is incorporated in many minerals on Earth was completely absent from lunar minerals.

This, actually, was predicted by the early lunar scientists. Water will evaporate at any atmospheric pressure and ice will sublimate at lunar temperatures and vacuum. Given the energetic solar radiation and '''wind''' the water molecules would be atomized and accelerated out of the weak lunar gravity field. Otherwise there would be a slight atmosphere of water and other volatives around the moon.

Though some scientist theorized that ice might be found in the cold polar craters that have not been exposed to solar radiation for billions of years, especially if the ice was covered by lunar regolith, it was not until 1994 that evidence of lunar ice was found by the Clementine lunar probe. Ice has a left-polarized radar refelection that was observed by Clementine at both lunar poles. The evidence for ice on the moon was greatly strengthened by Lunar Prospector's neutron radiation data. Lunar Prospector observed the background or cosmic neutron radiation and the neutron radiation from the moon as it orbited. It found back scattered neutron energy consistent with hydrogen but only at the poles. Water was further confirmed by NASA's LCROSS lunar impact mission and India’s Chandrayaan-I lunar orbiter radar. The estimate of lunar ice has risen to millions of tons, somewhat more on the north pole than south.



== Water and Life ==

Water is of course a primary component of life as we know it. The near total lack of water on the Moon struck quite a blow to lunar settlement plans. One of the components of water, oxygen, is abundant on the Moon, since many lunar rocks are oxides. It will take energy and machines to win this oxygen. Some hydrogen is also trapped in the lunar regolith, deposited by the solar wind, but it is very thin (Blacic, ref. below, states 100 ppm by weight) (ppm = parts per million). Finding hydrogen deposits in the cold trap areas of the lunar poles, presumably water ice but possibly some other ices as well, such as methane (CH4), has caused many planners to regard the poles as initial base candidates. Such hydrogen as can be found there, in whatever form, should probably not be squandered, but kept religiously in the lunar economy, being circulated and recirculated as water, carbohydrates, etc.

== Water and Fuel ==
Some people see the ice deposits at the lunar pole cold traps as a source of cheap [[In-Situ_Propellant_Production|rocket fuel]]. Hydrogen, though, is used to reduce metal oxides to metals releasing the oxygen in the ore as water. The water would then be hydrolyzed to recycle the hydrogen and produce pure oxygen. Use as a fuel would be extremely wasteful of a vital ore processing resource, at least until a better or cheaper hydrogen source can be found from comets or outer moons. Other substances, such as [[In-Situ_Propellant_Production#Aluminum | aluminum]] or magnesium with oxygen should be used for rocket fuel. These elements are very abundant on the moon.

== Water and Glass ==

In '''''Lunar Bases and Space Activities of the Twenty-first Century''''' (W.W. Mendell, ed., 1985), James D. Blacic of Los Alamos National Laboratory wrote about "Mechanical Properties of Lunar Materials Under Anhydrous, Hard Vacuum Conditions: Applications of Lunar Glass Structural Components" (p.487). He states that, "Hydrolysis of Si-O bonds at crack tips or dislocations reduces the strength of silicates by about an order of magnitude in Earth environments." This means that lunar anhydrous glass is about an order of magnitude (10x) stronger than Earth glass we are familiar with, and can be useful as a structural component. Experiments confirm this. Anhydrous lunar glass or glass composites can be made into "a lightweight structural material with several hundred thousand psi tensile strength."

This also has implications for geology and material handling on the Moon. The glass fraction of regolith will be much harder than we would otherwise expect, and this will make tools and machines wear more quickly. In geology, it implies that the glass matrix component of lunar basalts (about 52% [http://volcanoes.usgs.gov/Products/Pglossary/basalt.html]) is much stronger on the Moon than on Earth, and this may translate to a much wider span being supportable than the roughly 340m theoretical maximum based on simple extrapolation of Earth basalt to the Moon (an order of magnitude, Earth maximum being approximately 30 meters). This possibility is supported by circumstantial evidence (Coombs & Hawke, 1992) that lunar lavatube caves may reach a kilometer or more in span (diameter). Note that due to the evidence of flowing water on Mars, its basalt may be no stronger than Earth basalt, and maximum size of its [[Lava Tubes|lavatubes]] may be roughly 150 meters (back of envelope calculation).

[[Category:Water Supply]]

FFC Cambridge Process

2011-08-12T16:51:12Z

205.208.203.59: /* Aluminum/Silicon/Calcium Production from Anorthite */

__TOC__

== Introduction ==

The FFC Cambridge Process reduces oxides to their metal components by electrolysis in a bath of molten [[calcium]] chloride. The process has potential to directly produce [[oxygen]] and metal from virtually any oxide. The process works by placing the oxide to be refined into a bath of molten calcium chloride and creating a voltage differential between the oxide component (which forms the cathode) and an anode which is also placed in the bath. Oxygen is stripped off the cathode, where it forms calcium oxide, which is soluble in the calcium chloride bath. This oxide is split at the anode, producing oxygen. The cathode meanwhile is gradually reduced to a porous metallic sponge.

The process is currently being developed by Metalysis<ref>http://www.metalysis.com/</ref> for terrestrial metal production, specifically for the production of titanium; the developers hope it will eventually replace the Kroll Process.

==Application To Lunar Colonization==
In a lunar environment, this process could enable much simpler resource extraction. Experiments have already been done using pellets of [[sintering|sintered]] lunar regolith stimulant, as well as a non-consumable anode, producing metalized pellets and oxygen<ref>http://www.lpi.usra.edu/meetings/roundtable2006/pdf/tripuraneni.pdf</ref>.

===Aluminum/Silicon/Calcium Production from Anorthite===
[[Anorthite]] ([[Ca]][[Al]]2[[Si]]2[[O]]8), which makes up much of the Lunar Highlands, could be separated from the regolith by grinding, followed by electrostatic/magnetic [[beneficiation]], and then sintered into an appropriate cathode. As the process progresses, the oxygen is stripped off, and metallic [[calcium]] is produced, which is soluble in the calcium chloride bath. To keep the calcium concentration from becoming too high (which can reduce current efficiencies), a distillation unit is set up to continuously remove the metallic calcium from the mix. Once the [[Anorthite]] cathode is completely reduced, a sponge consisting of approximately 49% [[Aluminum]], 51% [[Silicon]] remains. This sponge could then be melted and distilled under partial vacuum to produce pure [[aluminum]] and [[silicon]].

For every metric ton of Anorthite processed in this manner, approximately 460 kg [[oxygen]], 193 kg [[aluminum]], 201 kg [[silicon]], and 144 kg [[calcium]] would be obtained.

===Iron/Titanium Production from Ilmenite===
[[Ilmenite]] ([[Fe]][[Ti]][[O]]3), is found in abundance on the lunar Maria and is easily separated through magnetic means. This substance could be processed in the same fashion as [[Anorthite]], resulting in a 54% [[Iron]], 46% [[Titanium]] alloy. Separating this alloy into [[iron]] and [[titanium]] could be done by distillation, as with anorthite. However, separating iron and titanium by a carbonyl process could be more efficient and would result in more pure final product. For carbonyl separation, the sponge would be pulverized to a fine powder and treated with carbon monoxide to produce iron carbonyl, which would evaporate. The iron carbonyl is then separated and heat treated to produce iron and recover the carbon monoxide, leaving finely powdered [[iron]] and [[titanium]] as end products. This process is used terrestrially to produce very pure iron and nickel<ref>http://en.wikipedia.org/wiki/Carbonyl_iron</ref><ref>http://en.wikipedia.org/wiki/Mond_process</ref>.

Another option is to first subject the [[Ilmenite]] to [[Ilmenite_Reduction#Hydrogen_Reduction|Hydrogen Reduction]], producing [[Iron]] and [[rutile|titanium dioxide]]. The iron could then be separated by carbonyl extraction, distillation, or grinding followed by use of a magnet. The remaining titanium dioxide could then be run through the FFC Cambridge process, producing a titanium sponge.

The end result for each ton would be approximately 316 kg [[Oxygen]], 316 kg [[Titanium]], and 368 kg [[Iron]].

===Other Products===
Lunar [[Chromite]] could also be reduced in the same fashion, producing Ferrochrome, which could be used to add [[Chromium]] content to [[Iron]] alloys. Many of the above listed reductions would also contain amounts of [[Magnesium]] and [[Sodium]] (Lunar [[Ilmenite]] in particular is known to be highly enriched with [[Magnesium]]), which could be distilled out fairly easily due to their low melting points.

===Chlorine Recovery===
The only substance used which is not readily available on the Lunar surface is [[chlorine]]. Chlorine is avalible on the lunar surface in the form of [[Apatite]] ([[Ca]]10([[P]][[O]]4)6([[O]][[H]], [[F]], [[Cl]], [[Br]])2), but only in trace quantities. If a viable procedure for concentrating apatite out of the lunar regolith is not found, then a high degree of chlorine recycling would be necessary for the FFC Cambridge process to be useful in a lunar environment.

Chlorine losses from the system would come in the form of calcium chloride trapped in the pores of the metallic sponge produced in the reduction process, as well as any amount lost from the distillation of calcium metal out of the bath during anorthite processing. The latter losses could be reduced to acceptable levels through careful design of the distillation equipment.

In terrestrial applications, the salt trapped in the pores of the sponge is removed by grinding the sponge and washing the resulting powder with water, as calcium chloride is highly water soluble. The same procedure could be followed in a lunar environment, followed by reverse osmosis and distillation to recover the dissolved salt.

A simpler method is to melt the sponge, as is required for most of the described processes already. Since calcium chloride is not soluble in (and less dense than) most metals, it should separate into a distinct top layer, where it can be easily drained off, while the metallic elements are drained from the bottom.

== References ==
<references/>

== External Links ==
[http://en.wikipedia.org/wiki/Ffc_cambridge_process FFC Cambridge process on Wikipedia]

[[Category:Industrial Production]]

FFC Cambridge Process

2011-08-12T08:28:32Z

205.208.203.59: /* Iron/Titanium Production from Ilmenite */

__TOC__

== Introduction ==

The FFC Cambridge Process reduces oxides to their metal components by electrolysis in a bath of molten [[calcium]] chloride. The process has potential to directly produce [[oxygen]] and metal from virtually any oxide. The process works by placing the oxide to be refined into a bath of molten calcium chloride and creating a voltage differential between the oxide component (which forms the cathode) and an anode which is also placed in the bath. Oxygen is stripped off the cathode, where it forms calcium oxide, which is soluble in the calcium chloride bath. This oxide is split at the anode, producing oxygen. The cathode meanwhile is gradually reduced to a porous metallic sponge.

The process is currently being developed by Metalysis<ref>http://www.metalysis.com/</ref> for terrestrial metal production, specifically for the production of titanium; the developers hope it will eventually replace the Kroll Process.

==Application To Lunar Colonization==
In a lunar environment, this process could enable much simpler resource extraction. Experiments have already been done using pellets of [[sintering|sintered]] lunar regolith stimulant, as well as a non-consumable anode, producing metalized pellets and oxygen<ref>http://www.lpi.usra.edu/meetings/roundtable2006/pdf/tripuraneni.pdf</ref>.

===Aluminum/Silicon/Calcium Production from Anorthite===
[[Anorthite]] ([[Ca]][[Al]]2[[Si]]2[[O]]8), which makes up much of the Lunar Highlands, could be separated from the regolith by grinding, followed by electrostatic/magnetic [[benefication]], and then sintered into an appropriate cathode. As the process progresses, the oxygen is stripped off, and metallic [[calcium]] is produced, which is soluble in the calcium chloride bath. To keep the calcium concentration from becoming too high (which can reduce current efficiencies), a distillation unit is set up to continuously remove the metallic calcium from the mix. Once the [[Anorthite]] cathode is completely reduced, a sponge consisting of approximately 49% [[Aluminum]], 51% [[Silicon]] remains. This sponge could then be melted and distilled under partial vacuum to produce pure [[aluminum]] and [[silicon]].

For every metric ton of Anorthite processed in this manner, approximately 460 kg [[oxygen]], 193 kg [[aluminum]], 201 kg [[silicon]], and 144 kg [[calcium]] would be obtained.

===Iron/Titanium Production from Ilmenite===
[[Ilmenite]] ([[Fe]][[Ti]][[O]]3), is found in abundance on the lunar Maria and is easily separated through magnetic means. This substance could be processed in the same fashion as [[Anorthite]], resulting in a 54% [[Iron]], 46% [[Titanium]] alloy. Separating this alloy into [[iron]] and [[titanium]] could be done by distillation, as with anorthite. However, separating iron and titanium by a carbonyl process could be more efficient and would result in more pure final product. For carbonyl separation, the sponge would be pulverized to a fine powder and treated with carbon monoxide to produce iron carbonyl, which would evaporate. The iron carbonyl is then separated and heat treated to produce iron and recover the carbon monoxide, leaving finely powdered [[iron]] and [[titanium]] as end products. This process is used terrestrially to produce very pure iron and nickel<ref>http://en.wikipedia.org/wiki/Carbonyl_iron</ref><ref>http://en.wikipedia.org/wiki/Mond_process</ref>.

Another option is to first subject the [[Ilmenite]] to [[Ilmenite_Reduction#Hydrogen_Reduction|Hydrogen Reduction]], producing [[Iron]] and [[rutile|titanium dioxide]]. The iron could then be separated by carbonyl extraction, distillation, or grinding followed by use of a magnet. The remaining titanium dioxide could then be run through the FFC Cambridge process, producing a titanium sponge.

The end result for each ton would be approximately 316 kg [[Oxygen]], 316 kg [[Titanium]], and 368 kg [[Iron]].

===Other Products===
Lunar [[Chromite]] could also be reduced in the same fashion, producing Ferrochrome, which could be used to add [[Chromium]] content to [[Iron]] alloys. Many of the above listed reductions would also contain amounts of [[Magnesium]] and [[Sodium]] (Lunar [[Ilmenite]] in particular is known to be highly enriched with [[Magnesium]]), which could be distilled out fairly easily due to their low melting points.

===Chlorine Recovery===
The only substance used which is not readily available on the Lunar surface is [[chlorine]]. Chlorine is avalible on the lunar surface in the form of [[Apatite]] ([[Ca]]10([[P]][[O]]4)6([[O]][[H]], [[F]], [[Cl]], [[Br]])2), but only in trace quantities. If a viable procedure for concentrating apatite out of the lunar regolith is not found, then a high degree of chlorine recycling would be necessary for the FFC Cambridge process to be useful in a lunar environment.

Chlorine losses from the system would come in the form of calcium chloride trapped in the pores of the metallic sponge produced in the reduction process, as well as any amount lost from the distillation of calcium metal out of the bath during anorthite processing. The latter losses could be reduced to acceptable levels through careful design of the distillation equipment.

In terrestrial applications, the salt trapped in the pores of the sponge is removed by grinding the sponge and washing the resulting powder with water, as calcium chloride is highly water soluble. The same procedure could be followed in a lunar environment, followed by reverse osmosis and distillation to recover the dissolved salt.

A simpler method is to melt the sponge, as is required for most of the described processes already. Since calcium chloride is not soluble in (and less dense than) most metals, it should separate into a distinct top layer, where it can be easily drained off, while the metallic elements are drained from the bottom.

== References ==
<references/>

== External Links ==
[http://en.wikipedia.org/wiki/Ffc_cambridge_process FFC Cambridge process on Wikipedia]

[[Category:Industrial Production]]

Titanium

2011-08-08T20:10:59Z

205.208.203.59: available=abundant

{{Element |
name=Titanium |
symbol=Ti |
available=abundant |
need= |
number=22 |
mass=47.867 |
group=4 |
period=4 |
phase=Solid |
series=Transition Metals |
density=4.506 g/cm3 |
melts=1941K, 1668°C, 3034°F |
boils=3560K, 3287°C, 5949°F |
isotopes=46 50 |
prior=[[Scandium|Sc]] |
next=[[Vanadium|V]] |
above=N/A |
aprior=N/A |
anext=N/A |
below=[[Zirconium|Zr]] |
bprior=[[Yttrium|Y]] |
bnext=[[Niobium|Nb]] |
radius=140 |
bohr=176 |
covalent=136 |
vdwr= |
irad=(+4) 61 |
ipot=6.83 |
econfig=1s2 2s2 2p6 3s2 3p6 3d2 4s2 |
eshell=2, 8, 10, 2 |
enega=1.54 |
eaffin=0.08 |
oxstat=4 |
magn=Paramagnetic |
cryst=Hexagonal |
}}
'''Titanium''' is a Transition Metal in group 4.
It has a Hexagonal crystalline structure.
This element has two stable isotopes: 46 and 50.
 
"Titanium occurs primarily in the minerals anatase, brookite, [[ilmenite]], leucoxene, perovskite, [[rutile]], and sphene. Of these minerals, only ilmenite, leucoxene, and rutile have significant economic importance. As a metal, titanium is well known for corrosion resistance and for its high strength-to-weight ratio. Approximately 95% of titanium is consumed in the form of [[titanium dioxide]] (TiO2), a white pigment in paints, paper, and plastics. TiO2 pigment is characterized by its purity, refractive index, particle size, and surface properties. To develop optimum pigment properties, the particle size is controlled within the range of about 0.2 to 0.4 micrometer. The superiority of TiO2 as a white pigment is due mainly to its high refractive index and resulting light-scattering ability, which impart excellent hiding power and brightness." - USGS Titanium Statistics and Information[http://minerals.usgs.gov/minerals/pubs/commodity/titanium/]
 

== Lunar Titanium Process ==
Main Article [[Lunar Titanium Production]]

There are questions to be settled about processing ores into titanium stock and finished products on Luna. What sort of casting is suitable for titanium on Luna? Today on Earth most titanium is produced by the Kroll process using rutile, natural or artificial. Can an economic process be developed for Luna using lunar [[ilmenite]]? Can ilmenite be mechanically separated from iron oxide? Both are magnetic.

{{Autostub}}
[[Category:Abundant Elements]]
[[Category:Paramagnetic Elements]]
[[Category:Solids]]
[[Category:Transition Metals ]]

FFC Cambridge Process

2011-08-08T08:40:04Z

205.208.203.59: added chlorine recovery section, more in depth details

__TOC__

== Introduction ==

The FFC Cambridge Process reduces oxides to their metal components by electrolysis in a bath of molten calcium chloride. The process has potential to directly produce oxygen and metal from virtually any oxide. The process works by placing the oxide to be refined into a bath of molten calcium chloride and creating a voltage differential between the oxide component (which forms the cathode) and an anode which is also placed in the bath. Oxygen is stripped off the cathode, where it forms calcium oxide, which is soluble in the calcium chloride bath. This oxide is split at the anode, producing oxygen. The cathode meanwhile is gradually reduced to a porous metallic sponge.

The process is currently being developed by Metalysis for terrestrial metal production, specifically for the production of titanium; the developers hope it will eventually replace the Kroll Process.

==Application To Lunar Colonization==
In a lunar environment, this process could enable much simpler resource extraction. Experiments have already been done using pellets of [[sintering|sintered]] lunar regolith stimulant, producing metalized pellets and oxygen.

===Aluminum/Silicon/Calcium Production from Anorthite===
[[Anorthite]] ([[Ca]][[Al]]2[[Si]]2[[O]]8), which makes up much of the Lunar Highlands, could be separated from the regolith by electrostatic/magnetic [[benefication]], and then sintered into an appropriate cathode. As the process progresses, the oxygen is stripped off, and metallic [[calcium]] is produced, which is soluble in the calcium chloride bath. To keep the calcium concentration from becoming too high (which can reduce current efficiencies), a distillation unit is set up to continuously remove the metallic calcium from the mix. Once the [[Anorthite]] cathode is completely reduced, a sponge consisting of approximately 49% [[Aluminum]], 51% [[Silicon]] remains. This sponge could then be melted and distilled under partial vacuum to produce pure [[aluminum]] and [[silicon]]. For every metric ton of Anorthite processed in this manner, approximately 460 kg [[oxygen]], 193 kg [[aluminum]], 201 kg [[silicon]], and 144 kg [[calcium]] would be obtained.

===Iron/Titanium Production from Ilmenite===
[[Ilmenite]] ([[Fe]][[Ti]][[O]]3), is found in abundance on the lunar Maria and is easily separated through magnetic means. This substance would be processed in the same fashion as [[Anorthite]], resulting in a 54% [[Iron]], 46% [[Titanium]] alloy, which could then be distilled to produce [[Iron]] and [[Titanium]]. The end result for each ton would be approximately 316 kg [[Oxygen]], 316 kg [[Titanium]], and 368 kg [[Iron]].

===Other Products===
Lunar [[Chromite]] could also be reduced in the same fashion, producing Ferrochrome, which could be used to add [[Chromium]] content to [[Iron]] alloys. Many of the above listed reductions would also contain amounts of [[Magnesium]] and [[Sodium]] (Lunar Ilmenite in particular is known to be highly enriched with [[Magnesium]]), which could be distilled out fairly easily due to their low melting points.

===Chlorine Recovery===
The only substance used which is not readily available on the Lunar surface is [[chlorine]]. Chlorine is avalible on the lunar surface in the form of [[Apatite]] ([[Ca]]10([[P]][[O]]4)6([[O]][[H]], [[F]], [[Cl]], [[Br]])2), but only in trace quantities. If a viable procedure for concentrating apatite out of the lunar regolith is not found, then a high degree of chlorine recycling would be necessary for the FFC Cambridge process to be useful in a lunar environment.

Chlorine losses from the system would come in the form of calcium chloride trapped in the pores of the metallic sponge produced in the reduction process, as well as any amount lost from the distillation of calcium metal out of the bath during anorthite processing. The latter losses could be reduced to acceptable levels through careful design of the distillation equipment.

In terrestrial applications, the salt trapped in the pores of the sponge is removed by grinding the sponge and washing the resulting powder with water, as calcium chloride is highly water soluble. The same procedure could be followed in a lunar environment, followed by reverse osmosis and distillation to recover the dissolved salt.

A simpler method is to simply melt the sponge, as is required for most of the described processes already. Since calcium chloride is not soluble in most metals, it should separate into a distinct layer, where it can be easily drained off.

== External Links ==
[http://en.wikipedia.org/wiki/Ffc_cambridge_process FFC Cambridge process on Wikipedia]

[http://www.metalysis.com/ Metalysis Website]

[http://www.lpi.usra.edu/meetings/roundtable2006/pdf/tripuraneni.pdf FFC Cambridge experiment with Lunar Regolith simulant]

Lunar Settlement Artificial Atmosphere

2011-06-20T20:31:00Z

205.208.203.59: added link

The lunar colony will have a pressurized selection of acceptable gaseous environments. We have experimental knowledge with some artificial atmospheres,say, space stations like [[ISS into the Pacific|ISS]] or the [[MIR]]. Yet, we need to experiment more on the effects of long term exposure. On the Moon, the atmosphere will be made in accordance with the architecture followed. Some variables like the use of [[Air Lock]]s, the thickness and materials of the walls may change the gas composition, pressure and other variables.

== Gas Combination ==
See also: [[Atmosphere]]

Oxygen is expected to be a major by-product of [[manufacturing activities]] on the moon. As such, a pure oxygen atmosphere is attractive as it is likely to be the easiest (and hence, cheapest) gas to procure on the moon. A pure oxygen atmosphere also carries the advantages of allowing a much lower habitat pressure, and greatly simplifying the machinery needed to maintain the atmospheric mix. For these reasons, a pure oxygen atmosphere was utilized in the Gemini project, as well as the early designs of the Apollo spacecraft. However, some studies suggest that a pure oxygen atmosphere becomes poisonous to the inhabitants on long term exposure, making it unsuitable for a lunar habitat.<ref>Malina, Frank J., ed. Life Science Research and Lunar Medicine. London: A. Wheathon and Co. Ltd. 1967 pg. 3-4 </ref>

A combination of one or more [[inert gases]] with Oxygen would allow proper oxygenation over longer time-frames. A nitrogen-oxygen mix could be utilized, as it is in earths atmosphere, though the low availability of nitrogen in lunar soil (compared to other [[volatiles]]) could raise difficulties in this regard. Helium could also be added to the oxygen mix, as it is significantly more abundant in lunar soil. However, the addition of any appreciable quantities of Helium to the atmosphere would result in a higher vocal pitch for those persons breathing it, similar to (though less intense than) the effects of inhaling pure helium. This effect is currently seen on earth in very deep diving operations, where helium-oxygen mixes are utilized, sometimes facilitating the need for a digital voice alteration device.

== Lower Pressure ==

Plants <ref>Henninger, D. L., ed. Lunar Base Agriculture. Texas: NASA & Soil Science Society of America. ISBN 0- 89118-100-8 Introduction</ref> and Humans can live in lower pressure atmospheres properly oxygenated. The limit is clear: when the vapor of a liquid inside equals the pressure outside, the liquid boils. Blood and other body fluids will boil if an abrupt drop of the pressure occurs.

We would need to lower the pressure inside the buildings to lower the force applied to the walls (somewhere around 40kPa would be ideal for many structures). Also, precise atmospheric pressure controls would be needed to prevent gas leaking.

== See Also ==
*[[Atmosphere]]
*[[Lunar Atmosphere]]
*[[Lunar Life Support Parameters]]
*[[Lunar Settlement]]

== References ==
<references/>

Lunar Settlement Artificial Atmosphere

2011-06-20T20:29:19Z

205.208.203.59: /* Gas Combination */ expaned discussion of pure oxygen environment, added additional information to the use of nitrogen and helium in oxygen mixes, corrected lunar nitrogen avilability

The lunar colony will have a pressurized selection of acceptable gaseous environments. We have experimental knowledge with some artificial atmospheres,say, space stations like [[ISS into the Pacific|ISS]] or the [[MIR]]. Yet, we need to experiment more on the effects of long term exposure. On the Moon, the atmosphere will be made in accordance with the architecture followed. Some variables like the use of [[Air Lock]]s, the thickness and materials of the walls may change the gas composition, pressure and other variables.

== Gas Combination ==
See also: [[Atmosphere]]

Oxygen is expected to be a major by-product of [[manufacturing activities]] on the moon. As such, a pure oxygen atmosphere is attractive as it is likely to be the easiest (and hence, cheapest) gas to procure on the moon. A pure oxygen atmosphere also carries the advantages of allowing a much lower habitat pressure, and greatly simplifying the machinery needed to maintain the atmospheric mix. For these reasons, a pure oxygen atmosphere was utilized in the Gemini project, as well as the early designs of the Apollo spacecraft. However, some studies suggest that a pure oxygen atmosphere becomes poisonous to the inhabitants on long term exposure, making it unsuitable for a lunar habitat.<ref>Malina, Frank J., ed. Life Science Research and Lunar Medicine. London: A. Wheathon and Co. Ltd. 1967 pg. 3-4 </ref>

A combination of one or more [[inert gases]] with Oxygen would allow proper oxygenation over longer time-frames. A nitrogen-oxygen mix could be utilized, as it is in earths atmosphere, though the low availability of nitrogen in lunar soil (compared to other volatiles) could raise difficulties in this regard. Helium could also be added to the oxygen mix, as it is significantly more abundant in lunar soil. However, the addition of any appreciable quantities of Helium to the atmosphere would result in a higher vocal pitch for those persons breathing it, similar to (though less intense than) the effects of inhaling pure helium. This effect is currently seen on earth in very deep diving operations, where helium-oxygen mixes are utilized, sometimes facilitating the need for a digital voice alteration device.

== Lower Pressure ==

Plants <ref>Henninger, D. L., ed. Lunar Base Agriculture. Texas: NASA & Soil Science Society of America. ISBN 0- 89118-100-8 Introduction</ref> and Humans can live in lower pressure atmospheres properly oxygenated. The limit is clear: when the vapor of a liquid inside equals the pressure outside, the liquid boils. Blood and other body fluids will boil if an abrupt drop of the pressure occurs.

We would need to lower the pressure inside the buildings to lower the force applied to the walls (somewhere around 40kPa would be ideal for many structures). Also, precise atmospheric pressure controls would be needed to prevent gas leaking.

== See Also ==
*[[Atmosphere]]
*[[Lunar Atmosphere]]
*[[Lunar Life Support Parameters]]
*[[Lunar Settlement]]

== References ==
<references/>

Nitrogen

2011-06-20T19:41:33Z

205.208.203.59: nitrogen is availible in trace quantities in the lunar regolith

{{Element |
name=Nitrogen |
symbol=N |
available=trace |
need=essential |
number=7 |
mass=14.00674 |
group=15 |
period=2 |
phase=Gas |
series=Non-metals |
density=1.251 g/L |
melts=63.15K, -210.00°C, -346.00°F |
boils=77.36K, -195.79°C, -320.42°F |
isotopes=14 15 |
prior=[[Carbon|C]] |
next=[[Oxygen|O]] |
above=N/A |
aprior=N/A |
anext=N/A |
below=[[Phosphorus|P]] |
bprior=[[Silicon|Si]] |
bnext=[[Sulfur|S]] |
radius=65 |
bohr=56 |
covalent=75 |
vdwr=155 |
irad=(+3) 16 |
ipot=14.53 |
econfig=1s2 2s2 2p3 |
eshell=2, 5 |
enega=3.04 |
eaffin=Unstable anion |
oxstat=+/-'''3''', 5, 4, 2 |
magn= |
cryst=Hexagonal |
}}
'''Nitrogen''' is a Non-metal in group 15.
It has a Hexagonal crystalline structure.
This element has two stable isotopes: 14 and 15.
 
"Nitrogen (N) is an essential element of life and a part of all plant and animal proteins. Nitrogen can be produced in several ways. Some plants, such as soybeans and other legumes, recover nitrogen directly from the atmosphere or from the soil in a process know as "fixation," whereby the plant converts nitrogen into carbohydrates, essential amino acids, and proteins. Nitrogen is commercially recovered from the air as ammonia, which is produced by combining nitrogen in the atmosphere with hydrogen from natural gas. Ammonia is converted to other nitrogen compounds, the most important of which are urea (NH2CONH2), nitric acid (HNO3), ammonium nitrate (NH4NO3), and ammonium sulfate [(NH4)2SO4]. With the exception of nitric acid, these compounds are widely used as fertilizer." - USGS Nitrogen Statistics and Information[http://minerals.usgs.gov/minerals/pubs/commodity/nitrogen/]
 

{{Autostub}}
[[Category:Gases]]
[[Category:Non-metals ]]
[[Category:Critical and Essential Elements]]