摘要
以自制微米级分子筛为晶种,在清液体系中成功合成出高性能的T型分子筛膜,考察了硅铝比、水硅比、碱度及合成温度与时间等条件对膜的生长和渗透汽化性能的影响. 结果表明,在摩尔组成为1SiO2:0.015Al2O3:0.41(Na2O+K2O):30H2O 的清液体系中,于423K晶化6h的条件下可较快地形成一层厚度为5μm的连续致密纯相T型分子筛膜,较大缩短了膜合成时间且提高了膜致密性. 在优化条件下所合成的膜具有优良的分离性能和高重复性. 348K时,在10wt%水-90wt%异丙醇混合物体系中膜的渗透通量和分离因子分别高达4.20kg/(m2·h) 和 7800.
Zeolite T membranes with very good permeation performance were successfully synthesized on porous mullite supports by the secondary growth method with homemade microsized seeds from clear solutions.The influence of synthesis parameters such as the molar ratios of SiO 2 /Al 2 O 3 and H 2 O/SiO 2 ,alkalinity,synthesis temperature,and crystallization time on membrane growth and permeation performance was investigated systematically.It is found that these parameters strongly affect the zeolite T growth and pervaporation performance of the membranes.Under the optimized synthesis conditions of 1SiO 2 :0.015Al 2 O 3 :0.41(Na 2 O+K 2 O):30H 2 O,the crystallization time was shortened to 6 h at 423 K and a continuous and dense T-type zeolite layer as thin as 5 μm formed on the surface of the support.It significantly improved the membrane density and permselective properties.A permeation flux and separation factor of 4.20 kg/(m2·h) and 7800,respectively,were obtained with the as-synthesized membrane for 10 wt% water-90 wt% i-propanol mixtures at 348 K.It also exhibited a very good pervaporation performance for water/ethanol mixtures separation.This high quality zeolite T membrane could be reproducibly prepared.
出处
《催化学报》
CSCD
北大核心
2013年第3期542-547,共6页
基金
supported by the National Natural Science Foundation of China(20966003,21106059)
the National High Technology Research and Development Program of China(863 Program,2012AA03A609)
Jiangxi Provincial Department of Science and Technology(2010BGA01200,2010GQH0068,20122BAB203018)
Jiangxi Provincial Department of Education(GJJ11377)~~
关键词
T型分子筛膜
重复性
清液
二次生长法
渗透汽化
Zeolite T membrane
Reproducibility
Clear solution
Secondary growth
Pervaporation
