PVA/ P（AA-Co-AN）/ PVA渗透汽化膜的研究

Study of Pervaporation Performance of PVA/P（AA-Co-AN）/ PVA Membrane

摘要:

制备一种PVA/P(AA-Co-AN)/PVA复合膜用于甲醇/水溶液的分离，膜的主体部分P(AA-Co-AN)由添加纳米SiO2粉末的丙烯酸（AA）和丙烯腈（AN）通过溶液共聚制得，两侧为交联聚乙烯醇（PVA）。考察了复合膜在浓甲醇水溶液中的溶胀性能，探讨了浸泡液温度及浸泡液浓度对溶胀度的影响。测试了复合膜的力学性能。考察了不同单体配比n(AA):n(AN)情况下所制备的复合膜在不同料液浓度，不同温度下的渗透汽化性能。结果显示，复合膜在浓甲醇水溶液中具有良好的溶胀性能及渗透汽化性能；在n(AA):n(AN)=1:1情况下所制备的复合膜，对高浓度甲醇水溶液分离效果最佳，60℃时分离w(甲醇)=98%的水溶液，分离因子可达1534，通量为583 g/(m2•h)。

Abstract:

The PVA/P(AA-Co-AN)/PVA composite membrane was prepared to separate methanol from aqueous solution. Acrylic acid (AA) and acrylonitrile (AN) were synthesized by solution polymerization with nanometer SiO2. The copolymer solution P(AA-Co-AN) was made into main body of the membrane, with the polyvinyl alcohol (PVA) acetal membrane on both sides, to make the composite pervaporation membrane. The swelling behavior of membrane in methanol dense aqueous solution was explored. The effect of dipping temperature and concentration on the swelling degrees was also measured. Mechanical property of the membrane was investigated by stretching test. The performances of the membranes prepared with different n(AA):n(AN) ratio were investigated through pervaporation experiments at different temperatures and different feed composition. The results of swelling and pervaporation experiments show the membrane has an encouraging swelling and pervaporation behavior in methanol dense aqueous solution. The membrane prepared with n(AA):n(AN)=1:1 gave the highest separation factor of 1534 and a permeation flux of 583 g/(m2•h) at 60℃ in pervaporation of w(methanol)=98% aqueous solution.