2012 Volume 55 Issue 3 Pages 149-159
The strong acidity and remarkable molecular sieving effect of zeolites makes them especially important materials in industrial reactions and separation processes. The use of zeolites as membranes combines the advantages of inorganic membranes (high temperature stability and solvent resistance) with the zeolitic properties. Such zeolite membranes have potential uses as separation and reaction membranes, and as simultaneous reaction/separation membranes. A number of approaches have proved effective for modifying the properties of zeolite membranes, including the use of nano-crystalline zeolites for membrane preparation, regioselective deactivation of acid sites, and modification of zeolitic pore size. This review describes the synthesis of nano-crystalline zeolites by an emulsion method and the regioselective deactivation of acid sites by the catalytic cracking of silane (CCS) method. The effects of the crystal size and CCS treatment on the performance of the zeolite membrane are reviewed.