Description: This proposal addresses the fabrication & testing of monolithic, carbon-based multipollutant trace-contaminant (TC) sorbents for the spacesuit Exploration Portable Life Support System (xPLSS) used in Extravehicular Activities (EVAs). The innovations: (1) multipollutant TC control at the 7-day Spacecraft Maximum Allowable Concentration (SMAC); (2) thin-walled, vacuum-regenerable TC sorbents fabricated using 3D-printing; (3) pre-oxidation of polymer monoliths to prevent monolith melting during carbonization & activation; (4) the patented oxidation/activation step used to improve ammonia removal. Overall objective: to develop a multipollutant TC Control System (TCCS) that is rapidly vacuum-regenerable & that possesses weight, size, & power-requirement advantages over the state of the art. Phase 2 results: (1) demonstrated TC-removal efficiency sufficient to keep the TC concentration in the ventilation loop below 50% of 7-day SMAC; (2) 2 full-scale TC sorbent-monolith prototypes integrated with the Rapid-Cycle Amine (RCA) twin bed, & NH3-removal efficiency exceeded 80%; (3) synergy between the TCCS and the RCA unit discovered, thanks to which TC sorbent performance improved. Phase 2E objectives: (1) to optimize with respect to minimum sorbent weight & volume, in 1/6 scale, properties and performance of TC sorbent monoliths produced by carbonization & activation of 3D-printed polymer monoliths; (2) to implement complete integration of the redesigned full-scale TCCS with the Rapid-RCA twin bed; (3) to deliver a next-generation full-scale twin-monolith TCCS prototype to NASA. Phase 2E tasks: (1) TC Sorbent Monolith Fabrication & Optimization for Maximum Performance & Minimum Volume & Weight in 1/6 Scale; (2) 1/6-Scale and Full-Scale TCCS Twin-Monolith Prototype Design & Fabrication; (3) Full-Scale TCCS Prototype Integration with the RCA; (4) Long-Term Testing of the 1/6-Scale TCCS; (5) Testing of the Full-Scale Integrated TCCS/RCA System; (6) Technology Evaluation.

Benefits: The main application of the proposed technology would be in spacecraft life-support systems, mainly in extravehicular activities (space suit), but after modifications also in cabin-air revitalization.

The developed technology may find applications in air-revitalization on board US Navy submarines, in commercial and military aircraft, in the future air-conditioning systems for green buildings, and in advanced scuba-diving systems.