Oxidation and Combustion of Lithium and Magnesium Powders for Space Power Applications

Abstract

Combustion of metals could be used for generation of heat and electric power in space missions where the use of solar or nuclear energy is impossible or impractical. We have proposed to develop a power system where a metal powder bed burns with oxygen supplied by a chemical oxygen generator. In missions to Mars and Venus, in situ CO<sub>2</sub> could also be used as the oxidizer. Lithium and magnesium powders have been identified as promising fuels for this application. However, their oxidation and combustion in oxygen and carbon dioxide is not well understood. Here we summarize the results of our recent studies performed to address these gaps in knowledge. The combustion experiments with lithium and magnesium powders at natural infiltration of oxygen have shown that counterflow and coflow combustion waves can propagate consecutively over the same sample. Using isothermal and non-isothermal methods of thermal analysis, the oxidation kinetics of lithium and magnesium powders in oxygen and carbon dioxide environments have been revealed.