水溶性带电聚合物黏结剂修饰炭电极用于增强电容去离子性能

Carbon electrodes modified with water-soluble charged polymer binder for enhanced capacitive deionization performance

电容去离子技术(capacitive deionization,CDI)是一种基于电吸附原理的新型脱盐技术,具有成本低、无污染、能耗小等优点。采用亲水性的羧甲基纤维素钠(CMC)和聚乙烯醇(PVA)黏结剂及其化学修饰得到的具有更多带电基团的磺化羧甲基纤维素(SCMC)和季铵化聚乙烯醇(QPVA)黏结剂制备活性炭电极,能进一步增强活性炭(AC)电极的亲水性和离子选择性。亲水性带电聚合物黏结剂依靠自身的电荷可以有效抑制阳极氧化的副反应,并增强离子吸附驱动力。在500 mg/L NaCl盐溶液,1.2/0 V电压下,AC-CMC//AC-PVA和AC SCMC//AC-QPVA可分别获得14.58和17.39 mg/g的脱盐量,且在0.8/0 V电压下循环100圈之后,脱盐量的保持率分别为65.48%和80.53%。

Capacitive deionization(CDI)is a new desalination technology based on the principle of electrosorption,which has the advantages of low cost,no secondary pollution,and low energy consumption.The hydrophilic binders carboxymethyl cellulose sodium(CMC),polyvinyl alcohol(PVA)and sulfonated carboxymethyl cellulose sodium(SCMC),quaternized polyvinyl alcohol(QPVA)were used to prepare the activated carbon electrodes,which further enhanced the hydrophilicity and ion selectivity of activated carbon(AC)electrodes.The hydrophilic charged polymer binder can effectively inhibit the anodic oxidation reaction and enhance the driving force of ion adsorption by virtue of its own charge.In 500 mg/L NaCl salt solution at 1.2/0 V,AC-CMC//AC-PVA and AC-SCMC//AC QPVA can obtain 14.58 and 17.39 mg/g of desalination,respectively,And after 100 cycles at 0.8/0 V,the retention rates of desalination were 65.48%and 80.53%,respectively.