H2/CO2 permeation through a silicalite-1 composite membrane

Journal article, 2011

Single and binary H2/CO2 gas permeation was studied through a silicalite-1 composite membrane consisting of a thin zeolite film (< 1 µm) supported on α-alumina. The temperature range for permeation measurements was 25 to 300°C. To determine the quality of the membrane, i.e the quantity and size of defects, n-hexane/helium permporometry measurements were performed. In general, single component fluxes decreased with increasing temperature whereas binary component fluxes showed a maximum value followed by a continuous decrease. A mass transport model that takes into account the surface diffusion and gas translational diffusion in the zeolite pores, Knudsen diffusion in defects, as well as viscous flow and Knudsen diffusion in the support material was developed to simulate the single and binary gas permeation measurements.