Title: Lime Production From Lunar Anorthite

Author(s): Donald M. Burt

Publication: Symposium Paper

Volume: 125

Issue:

Appears on pages(s): 237-244

Keywords: aluminum; anorthite; concretes; electrolysis; fluorination; fluorite; lime; lunar bases; lunar rock; oxygen; production methods; silicon; sodium fluorides; Materials Research

DOI: 10.14359/2435

Date: 5/1/1991

Abstract:
An important aspect of lunar concrete production will be the production of lime (CaO) from lunar rocks. Chemical and thermodynamic data show that lime could most easily be distracted from abundant lunar anorthite (CaAl2Si2O8) the major mineral in the anorthositic lunar highlands. If fluorine gas, produced on site by electrolysis of molten NaF, is used as the extracting agent, oxygen, silicon, and aluminum can be recovered at the same time. Of these, oxygen is likely to be the most valuable product. Lime is recovered from fluorite, CaF2, by reaction with soda, Na2O; the resulting NaF is recycled into fluorine production immediately before use. No fluorine gas is transported or stored in this process; it is used up as soon as it is made.