(551f) Two-Stage Varying-Temperature Synthesis of High-Performance SAPO-34 Membranes for H2/N2 Separation at High Temperature

Hydrogen has attracted worldwide attention in last decades for its combined advantages of high energy transferring efficiency and zero pollution emission. Especially, the demand of high-purity H₂ for PEM fuel cells requires new techniques for H₂ production with higher separation efficiency and lower cost. Membrane separation can be used for hydrogen purification with low energy consumption and ease of operation. Among those membrane-based separation techniques, the separation of gases in harsh conditions with zeolite membranes attracted tremendous interest due to its well-defined pore size, chemical, thermal and mechanical stability. In this work, high-performance SAPO-34 membranes on ceramic hollow fibers were successfully prepared by a two-stage varying temperature synthesis approach. The influence of synthesis parameters, such as precursor composition, synthesis temperature and duration, and seeding, on the microstructure evolution and separation performance of SAPO-34 membranes were investigated systematically. Finally, SAPO-34 membranes with high H₂ permeance of 4.0×10^-7 mol·m^-2·s^-1·Pa^-1 and H₂/N₂ selectivity of 15 were achieved at 400 °C and pressure drop of 1.1 MPa. Long-term stability testing results indicated that the obtained membranes were stable at 400 °C for over 12 h.