Synthesis and Characterization of Silicalite-1 Zeolite Membrane for Xylene Separation

MFI-type zeolite membranes have shown promising, particularly for those molecular sieve applications which require high chemical and thermal stability. In this work, MFI-type zeolite membranes were prepared by means of seeded growth method. Presence of binder (HPC: Hydroxy propyl cellulous) in the suspension solution was also investigated in order to minimize the intercrystalline gaps as well as the formation of continuous zeolite layer on the support. It was found that the presence of binder in the suspension solution minimizes the intercrystalline gaps while the latter cannot eliminate the destroying effect of template removal step. Isomorphous substitution of Ti and V in MFI structure and the synthesis of TS-1 and VS-1 zeolites were also performed in order to change the zeolite structure and thus to improve the adsorption of desirable isomers. Pervaporation experiments were conducted at different temperatures to examine the zeolite capability for xylene separation.