Vapor phase transport synthesis of un-supported ZSM-22 catalytic membranes

ZSM-22 has been synthesized from a dry amorphous gel via vapor phase transp ort crystallization, as bulk crystalline powder as well as an un-supported membrane. Crystalline products were characterized by powder X-ray diffracti on, scanning electron microscopy, Fourier transform infrared spectroscopy, chemical analysis, and thermal analysis. Catalytic testing was performed to demonstrate the membrane's ability to perform as an on-line catalyst. The ZSM-22 catalytic membrane showed 1-butene to isobutene conversions in exces s of 60% with selectivites close to 40%, which compares well with conventio nally synthesized bulk crystals. (C) 2001 Elsevier Science B.V. All rights reserved.