TiO_2光催化法降解空气中的苯

Degradation of Benzene in Air by TiO_2 Photocatalytic Process

以紫外灯为光源,采用P25型TiO2光催化降解空气中的苯。为保证TiO2的高分散性、增加其在铝板上的附着牢固性,加入了聚乙烯醇和硅溶胶,这在一定程度上增加了催化剂对光能的利用率,但也造成了催化剂活性的降低。实验结果表明:苯的光催化降解反应属一级动力学反应;苯降解率随初始苯质量浓度的增加而减小,随反应面积的增大而增大,在253.7 nm波长光源下的降解效果优于365.0 nm;苯降解所得的气相产物主要为CO2和CO;随使用次数的增加,催化剂失活现象逐步显现;双氧水对催化剂的再生效果优于去离子水。

Benzene in air was photocatalyticly degraded using UV lamp as light source and TiO2-P25 as catalyst. In order to make TiO2 dispersed well and enhance its fastness on Al board, polyvinyl alcohol and silica sol were added into TiO2 powder, which increased the light efficiency of the catalyst and decreased its photocatalytic activity. The experimental results show that： the photocatalytic degradation reaction of benzene is a first order kinetics process; The benzene degradation rate is decreased with the increasing of initial benzene mass concentration and increased with the increasing of reaction area, and the degradation effect under 253.7 nm of wavelength is better than that under 365.0 nm; The main gas phase degradation products are CO2 and CO; With the increasing of usage times, the catalyst deactivates gradually; The effect of H2O2 on regeneration of the catalyst is better than that of deionized water.