TL;DR: Hydrogen Reduction is a main entry in the 外星矿物知识引擎 database.
Reduction of metal oxides (especially ilmenite) with hydrogen gas at 900-1100°C to produce water and metals
Method Type
Chemical Reduction
Input Material
Ilmenite-rich regolith (beneficiated preferred)
Output
H₂O (→ O₂ + H₂ via electrolysis) + metallic iron + TiO₂
Efficiency
High for ilmenite; moderate for bulk regolith
Space Viability
Excellent - hydrogen is recyclable; demonstrated with Apollo samples