Charcoal is almost pure carbon. It is producted by heating biological material (usually wood) in an anoxic environment, causing the volatiles to boil off. The process is essentially the same as that used to produce coke from coal.
- One possible use of charcoal in a Martian settlement is the creation of terra preta for the greenhouses.
- Beds of granular activated charcoal are used to filter organic compounds from water and air.
- If a colony biosphere had an excess of carbon, it could be sequestered and stored as charcoal.
- Carbon has a very high melting point. Charcoal, perhaps sintered, could be used as a low-strength refractory material in the anoxic atmosphere of Mars. (In Earth's atmosphere, the impurities give it a low ignition point and graphite must be used instead.)
- M.V. Kilgore, A.T. Mikell & D.L. Pierson - Microbiological issues of space life support systems in S.E. Churchill ed. Fundamentals of space life sciences 1997. ISBN 0-89464-051-8 p. 296.
- General Atomic, as quoted by Charles Barton in Does Nuclear Grade Graphite Burn? 2011.