Oxygen

Oxygen
O
In situ availability:	abundant
Necessity:	critical
Atomic number:	8
Atomic mass:	15.9994
group:	16
period:	2
normal phase:	Gas
series:	Non-metals
density:	1.429 g/L
melting point:	54.36K, -218.79°C, -361.82°F
boiling point:	0.20K, -182.95°C, -297.31°F
N/A ← N/A → N/A
N ← O → F
P ← S → Cl
Atomic radius (pm):	60
Bohr radius (pm):	48
Covalent radius (pm):	73
Van der Waals radius (pm):	152
ionic radius (pm):	(-2) 140
1st ion potential (eV):	13.62
Electron Configuration
1s2 2s2 2p4
Electrons Per Shell
2, 6
Electronegativity:	3.44
Electron Affinity:	1.46
Oxidation states:	-2
Magnetism:	Paramagnetic
Crystal structure:	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
• 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

• lunar oxygen process sequence discussion from Knudson and Gibson (1989) (note: a good summary of approaches, but somewhat out of date)
• Lunar processing links from David Dietzler
• 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."