Lunar Sulfur Capture System

The Lunar Sulfur Capture System (LSCS) is an innovative method to capture greater than 90 percent of sulfur gases evolved during thermal treatment of lunar soils. LSCS sorbents are based on lunar soil iron compounds that trap sulfur contained in hot in-situ resource utilization (ISRU) product gases. Small amounts of polishing sorbents are used as needed to reduce equilibrium sulfur concentrations to the ppm or sub-ppm level. The LSCS is an effective technology for protecting in-situ resource utilization (ISRU) hardware from damage caused by the corrosive effects of hydrogen sulfide (H2S) and other sulfur-containing gases. Saturated sorbents can be regenerated for reuse, and desorbed sulfur can be converted to elemental sulfur. Key process steps include bulk H2S capture on lunar soil, further capture of H2S on polishing sorbent, regeneration of soil sorbent for re-use, recovery of high-purity H2S, and conversion of H2S to elemental sulfur. The LSCS reduces the risk of using Earth-based sorbents for primary sulfur capture by ensuring a ready supply of sorbent in the event of poor regeneration performance or process upset. The LSCS primary sulfur sorbent can be used as a non-regenerable sorbent if necessary without significant consequence to the ISRU process.