Zeolite composite membranes were prepared for the separation of VOCs by the pressurized coating method. On the top of the composite membrane, TiO2, polyimide or polyethersulfone were coated by the same technique. 100 nm-sized ZSM-5 coated membranes show higher selectivity for n-hexane in n-hexane/benzene mixture than 500 nm sized ZSM-5 coated membrane. Composite membrane coated with 100 nm zeolite and polymer showed the highest selectivity (44) for n-hexane/benzene.
Kim HJ, Jung KT, Shul YG, Kim YW, "Tubular Zeolite/α-Al2O3 Membrane for the Separation of VOCs," Theories and Applications of Chemical Engineering, 3, 1998