Synthesis and characterization of a pure zeolitic membrane

Abstract

A new membranous material was synthesized, composed of a continuous intergrowth of 10-100 μm ZSM-5 crystals. The membrane was crystallized under hydrothermal conditions at 180°C on a variety of flat nonporous surfaces including Teflon, silver, and stainless steel and on the external surface of a porous Vycor disk. The permeability and selectivity of the membrane was measured for three bicomponent gas mixtures. The following permeability ratios were computed: O2 N2: 1.07; H2 CO: 1.62; n- C6H14 CH3C(CH3)2CH2CH3: 17.2. These results show that the material can discriminate between permeates at the molecular level because of shape-selective transport within the ZSM-5 pore system. © 1992.