TiO_2/AC复合光催化剂对苯和丁醛的气相光催化降解机理

Reaction Mechanisms for Gas-Phase Photocatalytic Degradation of Benzene and Butyraldehyde over TiO_2/AC Composite Photocatalyst

利用溶胶-凝胶并水热处理法制备了TiO2光催化剂和TiO2/AC复合光催化剂,在静态光催化反应器中研究了苯和丁醛的气相吸附和光催化降解,利气相色谱分析确定了生成的中间体.结果表明,TiO2/AC复合光催化剂比TiO2光催化剂具有较强的吸附能力和较高的光催化活性;在TiO2和TiO2/AC上,苯(或丁醛)光催化降解产生相同的中间体,表明在两种催化剂上发生的光催化反应遵循相同的机理,进而讨论了其可能的光催化氧化途径.

The TiO2 photocatalyst and TiO2/AC composite photocatalyst were prepared by sol-gel and hydrothermal treatment methods. In a static photocatalytic reactor, the gas-phase adsorption and photocatalytic degradation of benzene and butyraldehyde over the two photocatalysts were studied, and the intermediates and products were detected by gas chromatography. The TiO2/AC composite photocatalyst had stronger adsorption capability and higher photocatalytic activity than the TiO2 photocatalyst. The intermediates and products were the same over TiO2 and TiO2/AC, which indicated that the photocatalytic degradation of benzene （or butyraldehyde） over the two catalysts followed the same mechanism. The possible photocatalytic oxidation pathways were discussed.