Methane Post-Processing and Hydrogen Separation for Spacecraft Oxygen Loop Closure



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47th International Conference on Environmental Systems


State-of-the-art life support oxygen recovery technology on the International Space Station is based on the Sabatier reaction where only about half of the oxygen required for the crew is recovered from metabolic carbon dioxide (CO2). The Sabatier reaction produces water as the primary product and methane as a byproduct. Oxygen recovery is constrained by both the limited availability of reactant hydrogen from water electrolysis and Sabatier methane (CH4) being vented as a waste product resulting in a continuous loss of reactant hydrogen. Post-processing methane with the Plasma Pyrolysis Assembly (PPA) to recover this hydrogen has the potential to substantially increase oxygen recovery and thus dramatically reduce the logistical challenges associated with oxygen resupply. The PPA decomposes methane into predominantly hydrogen and acetylene. A purification system is necessary to remove acetylene from the hydrogen before it is recycled back to the Sabatier reactor. Testing and evaluation of acetylene removal systems and PPA system architectures are presented and discussed.


Zach Greenwood, NASA Marshall Space Flight Center (MSFC), USA
Morgan Abney, NASA Marshall Space Flight Center (MSFC), USA
Lee Miller, Jacobs Technology, USA
Terry Wall, National Aeronautics and Space Administration (NASA), USA
ICES302: Physio-chemical Life Support- Air Revitalization Systems -Technology and Process Development
The 47th International Conference on Environmental Systems was held in South Carolina, USA on 16 July 2017 through 20 July 2017.


Methane, Post Processing, Plasma, Pyrolysis, Assembly, Oxygen, Carbon Dioxide, Recovery, Space craft, Space, Atmosphere, Closed loop, Loop Closure, International Space Station, Sabatier, acetylene