高通量T型分子筛膜的制备

The Synthesis of High-Flux Zeolite T Membranes

采用晶种诱导水热合成法，在配比n（SiO2）：n（Al2O3）：n（Na2O＋K2O）：n（NaF）：n（H2O）=1．00：0．05：0．35：0—1．00：35．00的溶胶中，于管状大孔陶瓷载体上合成了高通量T型分子筛膜．氟盐的添加大大促进了T型分子筛的晶化速度．在优化条件下，在大孔氧化铝和莫来石载体上合成了c轴取向的致密T型分子筛晶体层，且表现出高的渗透汽化性能．在75℃时，在氧化铝载体上合成的分子筛膜在水／乙醇质量比为10／90体系中的平均渗透通量和分离因子分别为（3．01±0．15）kg·m^-2·h^-1和2140±100，比在莫来石载体上形成膜的平均分离因子升高31．29％，而渗透通量降低13．11％．同时研究了原料液浓度和分离温度对T型分子筛膜的渗透汽化性能的影响．

Zeolite T membranes were synthesized by seed-induced hydrothermal synthesis using a gel with a molar ratio of n（ SiO2 ） ： n（ Al2O3 ） ： n（ Na2O ＋ K2O） ： n（NaF） ： n（H2O） = 1.00： 0.05： 0.35： 0.50：35.00 on macroporous tubular ceramics supports. The addition of fluoride salts promoted the crystallization of supported zeolite T layers. Under optimized conditions, the c-oriented compact zeolite T layers were synthesized on macroporous mullite and α-Al2O3 tubes. The membranes synthesized on α-Al2O3 tubes had an average total flux of（3.01 ±0.14）kg ·m^-2· h^-1 and an average separation factor of 2 140 ± 100 for the 90wt% ethanol aqueous solution at 75 ℃ ,which are 31.29% higher and 13.11% lower, respectively, than those of the mullite-supported membranes. The effects of op- eration temperature and concentration of water on the pervaporation properties of the membranes were also investiga- ted.