Hydrophilic Ge‐ZSM‐5 zeolite membranes were synthesized on α‐Al2 O3 support modified by γ‐Al2 O3 film by in situ hydrothermal synthesis method .The effect of template a‐mount and crystallization temperature on the microstructure of membranes was investigated .The results show that when the template amount was low (n(TPAOH)/n(SiO2 )=0.03) ,the zeolite membrane was not dense;however , when the amount of template was further increased (n(TPAOH)/n(SiO2 )=0.04 ,0.05) ,the film became dense and continuous .Moreover ,when the crystallization temperature was 160 ℃ ,zeolite membranes were discontinuous ;when the crystallization temperature reached 170 ℃ or 180 ℃ ,continuous and dense zeolite membranes were obtained .When the gel composition molar ratio was n(GeO2 )∶ n(SiO2 )∶ n(TPAOH)∶n(H2 O)=0 .195∶19 .5∶0 .780∶438 and its amount was 19 mL ,crystallization temperature and time was 180 ℃ and 24 h respectively ,continuous and dense Ge‐ZSM‐5 zeolite membrane with the thickness of 34 μm was obtained .When it was used to separate 95% ethanol aqueous solution at 70 ℃ by pervaporation ,the flux was 0.976 kg/(m2 · h) with a separation factor of 64.7 .%采用原位水热合成法，在γ‐Al2 O3膜修饰后的α‐AL2 O3载体上制备了亲水性 Ge‐ZSM‐5沸石膜，探讨了模板剂用量、晶化温度对膜微结构的影响。结果表明：模板剂用量低时（n （TPAOH）／n（SiO2）＝0.03），膜层不致密；增大模板剂用量（n（TPAOH）／n（SiO2）＝0.04，0.05），膜层致密连续；晶化温度较低时（160℃ ），膜层连续性差；升高晶化温度（170，180℃ ），得到致密连续膜层。当合成液摩尔比为 n（GeO2）∶ n（SiO2）∶ n（TPAOH）∶ n（H2O）＝0.195∶19.5∶0.780∶438，用量为19 m L ，180℃晶化24 h时，能合成出厚约34μm的致密连续膜层。该膜在70℃渗透蒸发质量分数为95％的乙醇水溶液，通量为0.976 kg／（m2· h），分离因子为64.7。
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