利用乙烯醇-乙烯胺共聚物制备交联可控的耐酸渗透蒸发脱盐复合膜

Controllable cross-linking of VA-co-VAm composite membrane for pervaporation desalination under acidic conditions

为了制备交联可控的耐酸脱盐膜,合成了同时含有羟基和氨基的乙烯醇-乙烯胺共聚物(VA-co-VAm),并基于酸性条件下羟基可以与醛发生缩醛反应的特性制备一系列交联可控的渗透蒸发脱盐膜。对聚合物材料和复合膜进行表征测试,研究聚合物组成、进料液p H等因素对脱盐性能的影响。结果表明,复合膜在酸性条件下表现出良好的脱盐性能,在60℃下处理质量浓度为35 g·L^(-1)的Na Cl溶液(p H=1),复合膜水通量超过12 kg·m^(-2)·h^(-1),盐截留率>99.95%。基于以上结果,所制备的膜为酸性条件下的高浓盐水脱盐处理提供了新的思路。

In order to prepare desalination membranes with controllable cross-linking degree and acid resistance,a vinyl alcohol-vinylamine copolymer(VA-co-VAm)containing both amino and hydroxyl groups was synthesized.The cross-linked membrane was prepared using glutaraldehyde as a cross-linking agent under acidic conditions.Cross-linking degree can be carefully controlled based on the reaction between glutaraldehyde and hydroxyl groups under acidic conditions.The polymer materials and composite membranes were characterized,and the effects of polymer composition,pH of feed solution,and other factors on membrane desalination performance were studied.The results show that the composite membrane exhibits good performance under acidic conditions.Specifically,the water flux of composite membrane exceeded 12 kg·m^(-2)·h^(-1) with salt rejection over 99.95%when treating a 35g·L^(-1) NaCl solution(pH=1)at 60℃.The prepared membrane offers a promising platform for desalination treatment of high salt concentrated water under acidic conditions.