Preparation and application of crosslinked polyvinyl alcohol in electrosorption
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摘要: 采用化学交联法制备聚乙烯醇(PVA)复合膜, 研究磺基琥珀酸(SSA)交联聚乙烯醇薄膜的电容去离子行为. 磺基琥珀酸作为一种交联剂和亲水基团的给体, 可以很好地应用于聚乙烯醇膜的改性. 详细研究了制备工艺(交联剂含量, 交联温度)对复合膜电容去离子性能的影响, 并进行对比实验, 将电容去离子系统(CDI)(仅使用活性炭电极)和采用了PVA与SSA交联的膜电容去离子系统(MCDI)(电极表面覆盖离子交换膜)分别进行吸脱附运行操作. 结果表明: 当交联剂SSA的质量分数为5%, 交联温度为100 ℃时, 交联聚乙烯醇复合膜在电容去离子中的应用使电极的吸附量增强了15%左右, 电荷效率平均提高了25%.Abstract: Sulfosuccinic acid (SSA) can be used as a crosslinking agent and a donor of a hydrophilic group when fabricating a cation exchange membrane. In this study, SSA was crosslinked with polyvinyl alcohol to form a cation exchange membrane for a capacitive deionization system. In this study, the impact of manufacturing parameters (i.e., crosslinker content, crosslinking temperature) on the deionization performance of a composite membrane were investigated in detail. A comparison was made between a capacitive deionization system (CDI) without an ion exchange membrane and a membrane capacitive deionization system (MCDI) coated with a PVA/SSA layer. The results show that the adsorption capacity and charge efficiency can be enhanced by 15% and 25%, respectively, with the PVA/SSA membrane layer; furthermore, the optimal mass fraction of SSA is 5%, and the optimal crosslinking temperature is 100 ℃.
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表 1 交联聚乙烯醇膜的成本
Tab. 1 Cost of cross-liked PVA membrane
材料 价格/元 总量/g 总用量/g 总价/(元·m–2) PVA 27 500 10 104.699 SSA 679.4 250 7.692 3 注: 每片电极所用膜重约0.025 g, 面积约为3 600 mm2 -
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