Large Scale Inert Anode for Molten Oxide Electrolysis

Molten oxide electrolysis is a demonstrated laboratory-scale process for producing oxygen from the JSC-1a lunar simulant; however, critical subsystems necessary for a larger-scale, lunar-ready reactor must be further developed to increase technology readiness. An enabling technology of the MOE system that must be scaled is the iridium inert anode. Iridium, a proven inert anode in the process, is expensive, scarce, extremely dense, and difficult to fabricate. Electrolytic Research Corporation will develop a larger-scale anode optimized for cost, weight, material availability, and manufacturability. ERC proposes an optimized iridium-based alloy or composite anode using electrochemical and thermophysical materials selection criteria validated with experiments (electrolysis testing) and modeling. The iridium alloy and composite screening will generate results necessary for Phase 2, where a surface engineered, multi-layer anode will be designed that includes either a refractory-metal or carbon substrate, a conductive diffusion-barrier inner layer, and an iridium outer layer. Completion of the work will greatly enhance the technology readiness level of the NASA molten oxide electrolysis in-situ resource utilization program.