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.
出处
《复合材料学报》
EI
CAS
CSCD
北大核心
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)