摘要
以氧化铝陶瓷膜为基底,采用化学气相沉积法制备了具有光催化性能的TiO2/多壁碳纳米管(MWNTs)/Al2O3复合分离膜,通过控制TiO2的沉积时间实现对膜孔径的有效调控.实验结果表明,当化学气相沉积时间为10min时,复合膜具有较好的纯水通量、截留性能和光催化性能.根据紫外漫反射谱图(DRS)分析,TiO2/MWNTs/Al2O3复合分离膜比单独的TiO2/Al2O3复合分离膜具有更好的光吸收性能,能量色散X射线光谱(EDX)的元素分布图显示,TiO2纳米颗粒均匀分布于复合膜表面.以浓度为15mg/L的腐植酸为目标物,考察了复合光催化膜的水处理性能,结果表明,光催化与膜分离耦合工艺可以显著提高有机污染物的去除效率,60min内对腐植酸的去除率可达80.9%,相比于单独的膜分离工艺高12.2%;同时能够有效缓解膜面污染,连续运行5h后,耦合工艺下复合膜的渗透通量比单独膜分离高70.9%.
TiO2/multi-walled nanotubes (MWNTs)/Al2O3 composite membrane was successfully fabricated by a two-step approach involving vacuum filtration of MWNTs suspension followed by chemical vapor deposition (CVD) of TiO2.The pore size of the as-prepared membrane was controlled by the deposition time of TiO2.Considering membrane flux and rejection as well as photocatalytic performance of composite membrane,the optimal deposition time of TiO2 was determined to be 10 min according to the experimental results.DRS results showed that TiO2/MWNTs/Al2O3 composite membrane exhibited better UV light absorption than bare TiO2/Al2O3 composite membrane.EDX map demonstrated that TiO2 was distributed well on the surface of interweaving MWNTs membrane.15 mg/L of humic acid (HA) was used as a target pollutant to investigate the water treatment performance of the composite photocatalytic membrane.By coupling membrane separation with photocatalysis technique,the removal efficiency of HA was 80.9% within 60 min,which was improved 12.2% when compared to membrane separation alone during the same time.HA permeate flux of filtration with UV light irradiation was 70.9% higher than that without UV after 5 h running,thus indicating good antifouling property of the composite membrane.
出处
《膜科学与技术》
CAS
CSCD
北大核心
2014年第4期26-32,共7页
Membrane Science and Technology
基金
国家自然科学基金项目(21077018)