Separation of H2-CO mixtures with porous glass membranes in the intermediate flow region.

Separations of H2-CO mixtures were studied in the intermediate flow region with four kinds of porous glass membranes of pore diameters 3.1, 5.8, 11 and 20 nm. Taking into account the change of viscosity in the flow direction, the observed data were analysed by the permeation equations proposed by Present and deBethune. The calculated results with these equations are in good agreement with the observed ones except that for the membrane of largest pore size. This deviation can be predicted by consideration of concentration polarization at the membrane surface on the high-pressure side because of high flux.