{HEAD ~ A process} 8 wherein the hydrogen diffusion membrane and {TAIL ~ the methanation catalyst} of the gas separation device function within similar temperature ranges 
wherein
{ HEAD ~ A process } 8 wherein the hydrogen diffusion membrane and { TAIL ~ the methanation catalyst } of the gas separation device function within similar temperature ranges
HEAD HEAD HEAD HEAD HEAD HEAD OTH REL OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH