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