Separation of light gas mixtures using zeolite SSZ-13 membranes

Abstract High-quality SSZ-13 membranes with enhanced permeances were synthesized on the symmetric mullite supports by modifying the synthesis recipes, and shown to be useful for light gas separations. The best SSZ-13 membrane displayed doubled CO 2 permeance and comparative CO 2 /CH 4 selectivities compared to our previous mullite supported SSZ-13 membranes. Single-gas permeance of CO 2 , H 2 , N 2 , CH 4 , C 2 H 6 and C 3 H 8 decreased at 298 K with increasing kinetic diameter, except for CO 2 . The CO 2 /CH 4 , CO 2 /N 2 , H 2 /CH 4 and N 2 /CH 4 ideal selectivities were 360, 20, 62 and 16, respectively, at room temperature. The mixture selectivities for the same equimolar gas pairs at 298 K were 406, 32, 43 and 16, and the faster-gas permeances of 4.4, 3.2, 1.8 and 0.22 mol/(m 2  s Pa), respectively. Calcination times, long-time operation and long-term storage had few effects on membrane performance.