Preparation of high-permeance ZSM-5 tubular membranes by varying-temperature synthesis

摘要

High-permeance ZSM-5 zeolite membranes were synthesized on porous α-alumina tubes bya varying-temperature in-situ hydrothermal treatment using n-butylamine(NBA) as atemplate. The membranes were characterized by XRD, SEM and single-gas permeationmeasurements. The highest H2 permeance is up to 2.3×10~(-6) mol/m~2·s·Pa, the highest idealselectivities are 201 for H_2/ n-C_4H_(10), 13 for n-C_4H_(10)/ i-C_4H_(10), at 293K. Few non-zeolite poresformed in the membrane when the sol was renewed during the varying-temperature process,so that the membrane had high ideal selectivity of n-C_4H_(10)/ i-C_4H_(10) above 473K.