生物柴油生产中甲醇脱水的NaA分子筛膜研究

PERVAPORATION DEHYDRATION OF METHANOL BY NaA ZEOLITE MEMBRANES IN BIODIESEL PRODUCTION

以水热法合成的NaA分子筛膜为研究对象,通过分离甲醇/水溶液、扫描电镜观测(SEM)及X射线衍射仪(XRD)等分析方法,对该膜的性能进行分析与实验验证。研究结果表明:按照物质的量之比Na2O:Al2O3:SiO2:H2O=48∶1∶5∶4500的配比,载体放置方式垂直向下,90℃水热合成4 h制备NaA分子筛膜,50℃分离95%甲醇/水溶液,分离系数最高达64.87。5次渗透汽化反应后,NaA分子筛膜仍表现出渗透汽化性能,为甲醇精馏及生物柴油低能耗生产提供可能。

Using NaA zeolite membranes as the research object,which are produced by hydrothermal synthesis. Their structures are characterized by separating methanol/water mixture,SEM and XRD. Zeolite membranes with high separation factor are obtained under the conditions below:molar composition of 48 Na2 O:1 Al2O3:5 SiO2:4500 H2 O,dipcoating seeding side downwards,hydrothermal synthesis at 90 ℃ for 4 hours. The methanol/water mixture with 95%,wt methanol content is separated at 50 ℃,separation factor is over 47.10. NaA zeolite membranes still show some pervaporation performance after be used for five times. It provides a probability for the methanol distillation and biodiesel production with low energy consumption.