壳聚糖改性TiO_2光催化剂的制备及其光催化性能研究

THE PREPARATION OF CTS MODIFIED TiO_2 AND ITS PHOTOCATALYTIC ACTIVITY

以钛酸丁酯为前驱物，无水乙醇为溶剂，采用溶胶-凝胶法制备了壳聚糖（CTS）改性TiO2光催化剂．考察了不同反应条件对溶胶形成的影响及其对甲基橙的光催化作用．结果表明，室温下体系的最佳配比（体积比）为无水乙醇：钛酸丁酯：二乙醇胺：去离子水=35：7：3：4，pH值取4．水解温度25～35℃，500℃灼烧2h后CTS完全分解，得到了具有光催化活性且分散性较好的锐钛矿TiO2．光催化实验表明：CTS改性TiO2的光催化效果较单纯TiO2的光催化效果有明显提高，60min后甲基橙质量浓度去除率由32％提高到48％，TOC去除率由14％提高到23％．

The process of preparing CTS modified TiO2 with Ti（ OBu）4 as precursor and C2H5OH as solvent by sol - gel method and its photocatalytic activity were investigated in this article. The influence of different factors was analysed. The results show that when the volume ratios C2H5OH： Ti（ OBu）4： inhibitor： water is 35： 7： 3： 4, pH value stays at 4, tempreture is between 25 - 35℃, and the steady TiO2 sol is obtained which contain anatase crystal TiO2 capable of photocatalysis. The characterization results show that CTS is discomposed absolutely and anatase is obtained. Furthermore, the photocatalytic activity of CTS modified TiO2 has more effective result than which of TiO2 alone. After 60 minutes, concentration removal rate has been proved from 32% to 48%, and TOC from 14% to 23%.