聚乙烯醇/壳聚糖共混膜渗透汽化性能研究  

Study on the pervaporation performance of poly(vinyl alcohol)/chitosan blend membranes

作　　者：刘兵兵[1] 曹义鸣[1] 李雄岩 贺晓泉 劳景水 吴志明 袁权[1] 

机构地区：[1]中国科学院大连化学物理研究所 [2]南海西部石油勘查设计公司,湛江524057

出　　处：《膜科学与技术》2007年第4期37-41,共5页Membrane Science and Technology

基　　金：国家973计划资助项目(No.2003CB615703)

摘　　要：制备了聚乙烯醇(PVA)/壳聚糖(CS)共混膜,用渗透汽化膜技术实现了甲醇/碳酸二甲酯二元共沸物的有效分离,研究了共混组成、操作温度、原料组成对膜分离性能的影响,结果表明,随着共混膜中CS含量的增加,膜的渗透通量增大,分离系数先增大后减小,当共混膜中CS含量为66%时,该膜具有优异的渗透汽化性能,有较大渗透汽化分离指数PSI值=660.8g/(m2.h).操作温度升高,膜的渗透通量增大,分离系数略微减小;随着原料中甲醇含量的增大,膜的渗透通量增大,分离系数减小.该共混膜在分离甲醇/碳酸二甲酯二元共沸物时得到的渗透侧甲醇的浓度远大于对应饱和蒸汽的浓度,表明用膜法渗透汽化分离是优于精馏分离的.Poly（vinyl alcohol）（PVA）/chitosan（CS） blend membranes were prepared and used to separate dimethyl carbonate（DMC）/methanol（MeOH） mixtures by pervaporation.The effects of blend composition,operating temperature and feed composition were investigated.With the increase of the CS content in the membrane,permeation flux increased and separation factor increased and then decreased.It was demonstrated that the membrane containing 66% CS exhibited good performance for the methanol/DMC separation and gave the highest Pervaporation Separation Index（PSI）（660.80 g·m^-2·h^-1）.With increasing temperature,the increase of flux and decrease of separation factor were observed.The permeation fluxes increased with increasing methanol concentration in feed.Increasing the concentration of methanol resulted in decreasing selectivities.It was clear that the concentration of methanol in the permeate was much higher than that in the saturated vapor over the entire concentration range.These results indicated that pervaporation was more efficient for methanol/DMC separation than distillation.

关 键 词：共混膜 甲醇 碳酸二甲酯 渗透汽化 

分 类 号：TB383.2[一般工业技术—材料科学与工程]