摘要
研究了Ｈ２ＳＯ４对壳聚糖（ＣＳ）膜醇水分离性能的影响．结果表明，Ｈ２ＳＯ４使ＣＳ上的—ＮＨ２质子化为—ＮＨ＋３，降低了极性较差的乙醇分子进入膜内的能力，提高了膜对水分子的吸附选择性．又因为ＳＯ２－４可以与２个—ＮＨ＋３作用，使部分ＣＳ链产生交联，缩小了分子透过的通道．由于乙醇分子比水分子大，故大大提高了膜对水的渗透选择性．所以，Ｈ２ＳＯ４能提高ＣＳ膜的醇水分离性能是以上两种因素综合作用的结果．
The separation factor (water/ethanol) of chitosan(CS) membrane was increased from 102 to 499 by addition of sulfuric acid to the water/ethanol mixture. The mechanism of the improvement has been investigated. It appeared that protonization of NH2 groups in CS decreases the ability of the more or less neutral ethanol molecules to pass through the CS membrane, increasing its adsorption selectivity to water molecules. In addition, partially crosslinking between CS chains may occur as a result of the reaction of SO2-4 with NH+3, that greatly increases the water permeability of the CS membrane.
出处
《应用化学》
CAS
CSCD
北大核心
1999年第2期65-68,共4页
Chinese Journal of Applied Chemistry
基金
浙江省自然科学基金
关键词
壳聚糖
渗透蒸发
乙醇
水
醇水分离
膜分离
chitosan,pervaporation membrane,water/ethanol mixture,sulfuric acid
