不锈钢金属网上L型分子筛膜的连续生长及气体渗透性能

选取不锈钢金属网作为成膜载体, 采用预涂晶种的方法, 研究了L型分子筛晶种在水热条件下二次生长成膜的过程. 对成膜条件进行了详细的考察, 并讨论了反应液的碱度及反应时间对L型分子筛膜形成的影响. 利用扫描电子显微镜(SEM)对L型分子筛膜的形貌进行了表征. 通过优化反应条件, 得到了致密、 连续、 纯相、 均匀的L型分子筛膜, 厚度约为20 μm. 单组分气体渗透测试结果表明, 在室温和常压下, L型分子筛膜对N₂气和H₂气的渗透速率分别为8.39×10^-8 和6.96×10^-7 mol·m^-2·s^-1·Pa^-1, 从而计算出膜对H₂/N₂混合气体的理想分离系数为8.3. 双组分气体渗透测试结果表明, 温度的升高会导致膜对H₂气和N₂气的渗透速率增加及H₂/N₂分离系数的减小.

Growth and Gas Permeation Properties of Continuous L-type Zeolite Membrane on Stainless Steel Net

Growth of L-type zeolite membrane on stainless steel net by the secondary hydrothermal growth was studied under different conditions. The effects of the alkalinity of the reaction solution and the reaction time on the formation of L-type zeolite membrane were discussed via the observation through scanning electron microscopy technique. The continuous uniform phase-pure L-type zeolite membrane was obtained with a thickness of about 20 μm. Single gas permeation measurement on the as-synthesized L-type membrane demonstrates that the permeance of N2 and H2 are 8.39×10-8 and 6.96×10-7 mol·m-2·s-1·Pa-1 respectively, indicating an ideal selectivity for H2/N2 of 8.3. Binary gas permeation measurement demonstrates that the increase of temperature would strengthen the permeation of N2 and H2, but decrease the separation factor of H2/N2.