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Ｃｒ（Ⅵ）－４ＣＰ（４－氯苯酚）共存污染体系中Ｃｒ（Ⅵ）离子的紫外光致还原主要是由于Ｃｒ（Ⅵ）与４ＣＰ光解产物之间的氧化还原反应而引起的．Ｃｒ（Ⅵ）离子还原受光强和体系酸度影响较大，还原速率呈零级反应．随体系ｐＨ值增大，Ｃｒ（Ⅵ）离子还原速率下降．中性条件下，光反应结束后有沉淀产物生成，这对于采用光化学方法消除环境污染提供了很有意义的结果．４ＣＰ存在对Ｃｒ（Ⅵ）离子在ＴｉＯ２表面的暗态吸附没有影响．Ｃｒ（Ⅵ）－４ＣＰ－ＴｉＯ２体系中Ｃｒ（Ⅵ）离子的紫外光致还原主要包括了两种反应：Ｃｒ（Ⅵ）与４ＣＰ之间的均相反应以及Ｃｒ（Ⅵ）离子在ＴｉＯ２表面的光催化还原反应．一定波长紫外光下，排除Ｃｒ（Ⅵ）－４ＣＰ－ＴｉＯ２体系中的均相反应，使得４ＣＰ对Ｃｒ（Ⅵ）离子光催化还原反应的促进作用得以证实．
The UV photolysis of Cr (Ⅵ) ions in Cr (Ⅵ) -4CP (4-chlorophenol) coexisting pollution system is mainly caused by the redox reaction between Cr (Ⅵ) and 4CP photolysis products. Cr (Ⅵ) ion reduction by light intensity and system acidity greater impact, the reduction rate was zero order reaction. With the increase of pH value, the reduction rate of Cr (Ⅵ) ion decreased. Under neutral conditions, the precipitation of the product after the photoreaction is completed, which provides a very meaningful result for photochemical methods to eliminate environmental pollution. The presence of 4CP has no effect on the adsorption of Cr (VI) ion on the surface of TiO2. The UV photoreduction of Cr (Ⅵ) ions in Cr (Ⅵ) -4CP-TiO2 system mainly includes two reactions: the homogeneous reaction between Cr (Ⅵ) and 4CP and the photocatalytic activity of Cr (Ⅵ) ions on TiO2 surface Catalytic reduction. Under the UV light of a certain wavelength, the homogeneous reaction in the Cr (Ⅵ) -4CP-TiO2 system was excluded, and the promotion of 4CP on the photocatalytic reduction of Cr (Ⅵ) ion was confirmed.