Influences of Acid Post-Treatment on High Silica SSZ-13 Zeolite Membrane

Single gas permeance performance of the high silica SSZ-13 zeolite membrane (Si/Al = 79) was greatly improved by acid post-treatment in this work. Effects of post-treatment conditions, such as post-treatment temperature (25, 60, 80, and 100 °C) and time (0–2 h), acid concentration (0–0.6 H+ mol/L), and acid type (HCl, HNO3, H2SO4, and H3PO4), on the single gas permeance performance of the membrane were investigated in this study. Morphology and structure of the acid post-treated membrane is identical with the fresh high silica SSZ-13 zeolites by advance characterization results, only the amorphous on the zeolites surface is removed and filled into the intercrystalline by medium acid post-treatment, which could improve the gas permeance performance of the membranes greatly. When the post-treatment temperature, time, acid type, and H+ concentration are 25 °C, 0.5 h, H2SO4, and 0.4 mol/L, the CO2/CH4, CO2/N2, H2/CH4, and H2/SF6 ideal selectivity of the post-treated high silica SSZ-13 zeolite membrane are increased to 68, 10, 29, and 126 at 0.2 MPa and 25 °C, respectively.