Abstract High-quality zeolite ZSM-5 zeolite membranes were successfully synthesized on the outer surface of tubular α-alumina substrates by manipulating the microstructure of the zeolite layer using a new different-sized seeding (DSSM) in combination with a variable-temperature/time (VTT) methods. In this method the defects/microcracks in the bottom seed layer, which are filled by smaller seeds, are effectively eliminated using a designed temperature/time profile, resulting in a significant increase in selectivity without scarifying permeance. The effects of number and combination of seed layers, seed particle size, and the synthesis temperature-time profile on the microstructure, N2/SF6 gas permeation, and H2/CO2 separation performance of membranes are evaluated in detail. The synthesized ZSM-5 zeolite membranes show the microstructure of thin, fully inter-grown, and densified zeolite layer that is responsible for high selectivity without any negative effect on the permeance. The best synthesized defect-free ZSM-5 zeolite membranes on alumina supports exhibited a very low H2/CO2 selectivity of 0.1 with CO2 permeance of 3 × 10−5 mol m−2 s−1 Pa−1.

中文翻译：

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用于 CO2/H2 分离的高性能 ZSM-5 沸石膜的制备

摘要 通过使用新的不同尺寸晶种 (DSSM) 结合变温/时间控制沸石层的微观结构，在管状 α-氧化铝基材的外表面上成功合成了高质量沸石 ZSM-5 沸石膜。 (VTT) 方法。在这种方法中，底部种子层中的缺陷/微裂纹由较小的种子填充，使用设计的温度/时间曲线有效地消除了，从而显着提高了选择性，而不会破坏渗透性。详细评估了种子层的数量和组合、种子粒径和合成温度-时间曲线对膜的微观结构、N2/SF6 气体渗透和 H2/CO2 分离性能的影响。合成的 ZSM-5 沸石膜显示出薄的微结构，完全相互生长且致密的沸石层，具有高选择性，对渗透性没有任何负面影响。在氧化铝载体上合成的最佳无缺陷 ZSM-5 沸石膜表现出非常低的 H2/CO2 选择性为 0.1，CO2 渗透率为 3 × 10-5 mol m-2 s-1 Pa-1。