热浸渍晶种法制备高重复性NaA分子筛膜

利用热浸渍法和打磨法引入晶种合成NaA分子筛膜,将合成的NaA分子筛膜应用于乙醇/水混合体系,研究进料温度、进料侧压力及进料流量等对其分离性能的影响。结果表明,进料温度升高,渗透通量和分离因数呈增大趋势;进料侧压力增大,渗透通量增加,分离因数减小;进料流量增大,渗透通量明显增大,分离因数未发生明显变化。进料温度为75℃、进料侧压力为100kPa、相对真空度接近-0.1MPa、进料流量为16L/h时,所得NaA分子筛膜的渗透通量和分离因数分别为1.08kg.m-2.h-1和3 338,此时用于乙醇/水混合体系分离效果最佳。NaA分子筛膜的重复性高达80%。

Synthesis of NaA zeolite membranes of high repeatability by hot dip-coating method

NaA zeolite membranes were hydrothermally synthesized by hot dip-coating and rubbing methods.The synthesized membranes were applied in the process of ethanol dehydration,and the influences of feed temperature,feed side pressure,and feed flow rate on the membranes’ separation performance were investigated.The results indicate that,with the feed temperature increasing,the permeation flux and the separation factor both increase;with the feed side pressure increasing,the permeation flux increases while the separation factor decreases;and with the feed flow rate increasing,the permeation flux increases obviously but there’s no significant change with the separation factor.It is also found that,when the feed flow rate is 16 L/h at 75 ℃,the feed side pressure 100 kPa,the vacuum-0.1 MPa,the separation factor and the permeation flux of the membranes are 1.0 8kg·m-2·h-1 and 3 338,respectively,the membranes have the best performance in water/ethanol separation.Besides,the repeatability of the membranes is found to reach 80%.