In the July Issue of Planetary and Space Science there is a summary of research on beneficiation, the process used for separation of minerals from waste in lunar regolith to prepare feedstock for chemical reactions to produce oxygen. One of the most commonly studied processes is hydrogen reduction of ilmenite (FeTiO3), a mineral abundant in the lunar maria. This type of research is critical to prepare for situ resource utilization (ISRU) needed for lunar settlements.
Benefication processes use differences in physical properties (e.g., density, electromagnetic characteristics) to manipulate materials, most commonly (especially on Earth) with water to facilitate separation. This is not practical in space environments where large scale water use will be more challenging then on Earth. On the Moon, dry techniques such as magnetic or electrostatic process are better suited to this application. The authors describe the physics behind the beneficiation process for ISRU in the lunar environment and survey the research performed thus far on these methods with interesting recommendations for further studies.
