Separation of traces of CO from air using MFI-type zeolite membranes

MFI-type zeolite membranes prepared on stainless steel and alumina tubular supports were used to separate a CO/air mixture at very low CO concentrations (160 ppbv). The influence of the temperature, pressure gradient across the membrane, sweep gas and retentate gas flow rates in the performance of the membranes was studied. At 245 K, a CO/air separation factor of 3.14 was achieved.