Increased Oxygen Recovery Using Plasma Pyrolysis Technology and Electrochemical Hydrogen Separation



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2023 International Conference on Environmental Systems


Currently on the International Space Station, approximately 50% of the oxygen (O2) for the crew is recovered from metabolic carbon dioxide (CO2). Maximum O2 recovery is required to reduce resupply mass for long-duration manned missions. O2 recovery is constrained by the limited availability of reactant hydrogen (H2) from water (H2O) electrolysis, and Sabatier-produced methane (CH4) is vented as a waste product resulting in a continuous loss of reactant H2. The Plasma Pyrolysis Assembly (PPA) has the potential to substantially increase O2recovery by post-processing the Sabatier-produced methane to recover H2. The PPA decomposes CH4 into predominately H¬2 and acetylene (C2H2). A separation system is needed to purify the H¬2 from the PPA stream before it is recycled back to the Sabatier reactor. Two sub-scale electrochemical H2 separation systems, developed by Skyre, Incorporated, were delivered to NASA for evaluation. This report details the results of Phase I testing and evaluation of the C2H2 removal systems.


Kagen Crawford, NASA Marshall Space Flight Center, USA
Cara Black, NASA Marshall Space Flight Center, USA
Travis Quillen, Jacob Space Exploration Group, USA
ICES302: Physio-chemical Life Support- Air Revitalization Systems -Technology and Process Development
The 52nd International Conference on Environmental Systems was held in Calgary, Canada, on 16 July 2023 through 20 July 2023.


Oxygen Recovery, Closed-Loop, Methane Plasma Pyrolysis, Hydrogen Separation