以聚醚嵌段共聚酰胺(PEBA2533)为膜材料,采用干法相转化法制备性能优异的高分子膜,用于渗透汽化-结晶耦合(PVCC)分离系统中回收稀水溶液中的香兰素.采用扫描电子显微镜(SEM)对PEBA2533膜的形貌进行表征.考察原料液浓度、温度对膜渗透汽化性能的影响.结果表明:随着溶液浓度的增加,PEBA2533膜溶胀性能增加,说明PEBA2533能够优先吸附香兰素;随原料液浓度增加,香兰素渗透通量增加,分离因子略微下降;原料液温度增加,香兰素渗透通量和分离因子都增加;并通过Arrhenius方程计算得到香兰素比水对温度更加敏感.PVCC系统中控制一级冷凝器温度为2℃时,一级冷凝器中结晶态香兰素通量为39.52 g·m-2·h-1,纯度在99%以上.%The high performance poly(ether-block-amide) (PEBA2533) membrane was prepared by dry phase inversion method, and then used for separation of vanillin from dilute aqueous solutions in the pervaporation-crystallization coupling (PVCC) system. The structural morphology of PEBA2533 membranes were characterized by SEM. The effects of feed concentration and operating temperature on the pervaporation performances of membrane were investigated. The results showed that the swelling degree of PEBA2533 membrane increased with the increase of concentration. This indicated that PEBA2533 could preferentially adsorb vanillin. With the increase of the feed concentration, the flux of vanillin increased while the separation factor decreased slightly. The vanillin permeation flux and separation factor both increased as the operating temperature increased. The equation of Arrhenius indicated that vanillin was more sensitive to temperature than water. When the temperature of first condenser was controlled at 2℃ in the PVCC system, the flux of crystal vanillin in the first condenser was 39.52 g·m-2·h-1 and the purity was more than 99%.
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