负载型TiO2在印染废水降解中的失活及原因分析

研究了负载型TiO2光催化剂在印染废水降解中的失活及其产生的原因.实验结果说明,催化剂活性下降的主要原因有废水中不溶于水的染料等悬浮物和催化反应中产生的无定形碳在催化剂表面的吸附;高含量的无机离子对催化剂活性位的占据或在表面的沉积;长时间的使用和反复冲洗使TiO2负载量减少.通过同时采用灼烧和酸洗的方法可以使TiO2的活性恢复到新催化剂的69.5%.

Study on deactivation and its reasons of supported TiO2 photocatalyst in degradation of printing and dyeing wastewater

Deactivation and its reasons of supported TiO_2 photocatalyst in degradation of printing and dyeing wastewater were investigated . The results show that the possible reasons of the catalyst deactivation are as follows:the suspended substances such as slightly soluble dyes in the wastewater and uncrystallized c produced in the potocatalytic reaction are adsorped on the surface of TiO_2;some inorganic ions occupy the active center of photocatalyst,or precipitate on its surface;the supported quantity of TiO_2 decreases with long time use and repeated washing.Catalytic activity of TiO_2 can be restored to 69.5% of the initial value by igniting and rinsing with HCl.