电渗析用季铵化聚氯乙烯均相阴离子交换膜的制备

以1-甲基咪唑(N-MI)为季铵化试剂一步法对聚氯乙烯(PVC)功能化改性,并制备了均相PVC阴离子交换膜,避免了传统阴离子交换膜制备过程中的氯甲基化步骤。通过对比研究,优化后的PVC-N-MI-5表现出较好的综合性能。离子交换容量和迁移数分别高达2.89 mmol·g^–1和98.4%;吸水率和溶胀率分别为4.24%和0.21%,低于商业JAM-5阴离子交换膜(4.87%和3.33%);脱盐率、电流效率以及能耗分别为98.38%、55.8%和5.1 kW·h·(kg NaCl)^–1,可与商业JAM-5(93.0%、55.2%和4.6 kW·h·(kg NaCl)^–1)相比较。低廉的原料与简便的制备过程以及相对良好的电渗析应用性能,表明所制备的PVC-N-MI-5具有一定的应用前景。

Preparation of homogeneous anion exchange membrane based on quaternized PVC for electrodialysis

This work presents the preparation of homogeneous anion exchange membrane (AEM) based on quaternized polyvinyl chloride (PVC) via straight forward quaternization of PVC with 1-methylimidazole (N-MI). In particular, the preparation avoids the use of toxic chloromethylation. The optimized AEM PVC-N-MI-5 shows ion-exchange capacity (IEC) and transport number of 2.89 mmol·g^–1 and 98.4%, respectively. The water uptake and swelling ratio are 4.24% and 0.21%, lower than the commercial AEM JAM-5 (4.87% and 3.33%). The NaCl removal ratio, current efficiency and energy consumption of the as-prepared AEM were 98.38%、55.8% and 5.1 kW·h·(kg NaCl)^－1, respectively, comparable to commerical JAM-5(93.0%, 55.2% and 4.6 kW·h·(kg NaCl)^－1). The cost-effective PVC and relatively good performance are suggestive of the potential electrodialysis application.