“三明治”双极膜的制备及其在降解含酚废水中的应用  

Preparation of sandwich-type bipolar membrane and its application in the degradation of phenol

作　　者：任羽西[1] 陈震[1] 林金火[1] 

机构地区：[1]福建师范大学化学与材料学院,福州350007

出　　处：《复合材料学报》2012年第3期150-157,共8页Acta Materiae Compositae Sinica

基　　金：国家自然科学基金(51073037)

摘　　要：纳米TiO2上负载纳米Pt以制备纳米Pt/TiO2半导体光催化剂,壳聚糖(CS)经纳米Pt/TiO2改性后作为阴膜层材料,以羧甲基纤维素(CMC)作为阳膜层材料,分别用戊二醛与FeCl3对阴、阳膜层进行交联改性,制备了CMC-Pt/TiO2-CS双极膜,并将该复合膜作为降解高浓度含酚废水电解槽的隔膜。结果表明:Pt/TiO2光催化剂可促进双极膜中间层水的解离,大大降低双极膜的膜阻抗和电阻电压降(IR降);同时,Pt/TiO2光催化剂表面生成的羟基自由基(.OH)可直接作用于苯酚,使其彻底降解成无机小分子;紫外光照下在16.7mA.cm-2的电流密度下电解高浓度含酚废水80min后,CMC-Pt/TiO2-CS双极膜的苯酚降解率比CMC-TiO2-CS双极膜的苯酚降解率高12.7%;整个电解过程CMC-Pt/TiO2-CS双极膜的膜电阻电压降保持在0.9V。Chitosan： （CS） was modified with nano-Pt/TiO2 semiconductor photocatalyst （CS - Pt/TiO2 ） which was prepared by doping Pt on TiO2 in advance. CMC - Pt/TiO2 - CS bipolar membrane was then prepared using carboxymethyl cellulose （CMC） and CS - Pt/TiO2 which were cross - linked by FeC13 and glutaraldehyde, respectively. Sandwich-typed CMC- Pt/TiO2 -CS bipolar membrane, the composite membrane with fine protons and hydroxyl ion-permeability, was then applied as the septum of the electrolytic cell in the degradation of phenol. Nano-Pt/TiO2 semiconductor photocatalyst can not only generate hydroxyl radicals （ · OH） which can directly degrade phenol into the small inorganic molecules, but also promote water splitting at the intermediate layer of CMC-Pt/TiO2 -CS bipolar membrane and greatly reduce the impedance and resistance（IR） of bipolar membrane. Compared CMC - Pt/TiO2 - CS bipolar membrane with CMC - TiO2 - CS bipolar membrane under UV irradiation, the degradation rate of the former is 12.7%higher than that of the latter after 80 min electrolysis at the current density of 16.7 mA · cm^- 2, while IR drop of CMC- Pt/TiO2 - CS is as low as 0.9 V.

关 键 词：“三明治”双极膜 壳聚糖 纳米Pt/TiO2 半导体光催化剂 苯酚 

分 类 号：TB333[一般工业技术—材料科学与工程]