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研究了醇水混合液体系在经交联的聚乙二醇/壳聚糖共混膜中的渗透蒸发分离性能.讨论了共混膜组成、料液浓度和温度、膜下侧压力等对渗透蒸发性能的影响.结果发现聚乙二醇的掺入能大大提高壳聚糖膜的渗透通量,但分离因子降低.当料液乙醇质量分数为80%时,渗透通量及分离因子都随温度的升高而增加.料液中加入少量ZrOCl2能把分离因子从原来的8.8提高到74.同时发现膜下游侧压力不仅仅影响渗透组分在膜表面的蒸发,还影响整个渗透蒸发传质过程.
The pervaporation separation performance of alcohol-water mixture in cross-linked polyethylene glycol / chitosan blends was studied. The effects of the composition of the blend membrane, the concentration of the feed solution and the temperature, the pressure on the underside of the membrane on the pervaporation performance were discussed. The results showed that polyethylene glycol incorporation can greatly improve the permeation flux of chitosan membrane, but the separation factor decreased. When the mass fraction of ethanol in feed was 80%, the permeate flux and separation factor increased with the increase of temperature. Adding a small amount of ZrOCl2 in the feed liquid increases the separation factor from 8.8 to 74. It is also found that the pressure on the downstream side of the membrane not only affects the evaporation of the permeation component on the surface of the membrane, but also affects the mass transfer process of the whole pervaporation.