纳米TiO_2复合膜光催化和膜分离的耦合作用

Coupling performance of photocatalysis and separation for nano-TiO_2 composite membranes

以微孔陶瓷管为载体,采用阳离子表面活性剂十六烷基三甲基溴化铵(CTAB)辅助的溶胶-凝胶法制备了纳米TiO2复合超滤膜。以1 g/L聚丙烯酰胺(PAM)为料液(目标污染物),以膜截留率及膜通量为实验参数,研究了复合膜的光催化-膜分离耦合作用,耦合时的膜通量较单一膜分离的膜通量提高了60%;以0.5 g/L牛血清白蛋白(BSA)为模拟天然大分子料液,采用无光照料液过膜-紫外光照清水过膜的交替间歇运行方法,膜通量可恢复60%以上。

The nano-TiO2 composite membranes were prepared on the inner surface of porous ceramic tubes by hexadecyl trimethyl ammonium bromide （CTAB） assisted sol-gel method. With 1 g/L of polyacrylamide （PAM） as a test pollutant and the rejection rate and permeate flux of membrane as the experimental parameters, the coupling performance of composite membrane photocatalysis-membrane separation was investigated, and the permeate flux of the composite membrane under UV irradiating was increased by 60%, compared with the processes of membrane separation without UV. The permeate flux of the polluted composite membrane, which was beforehand used to filter the influent feed of 0.5 g/L of bovine serum albumin （BSA） without UV, was improved remarkably by 60% within 300 rain under UV irradiating with clean water as influent feed. The results indicate that the photoeatalytic activity of nano-TiO2 can prevent the composite membranes from fouling so as to obtain high permeate flux.