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随着体系ｐＨ值增大，Ｃｒ（ＶＩ）离子在ＴｉＯ２表面的吸附下降．当Ｃｒ（ＶＩ）离子初始浓度为３００μｍｏｌ／Ｌ时，其在ＴｉＯ２表面具有最大值吸附．Ｈ２ＰＯ４－阴离子及乙酸的存在对Ｃｒ（ＶＩ）离子的吸附有阻抑作用，甲酸存在会提高Ｃｒ（ＶＩ）离子的吸附．Ｃｒ（ＶＩ）离子在ＴｉＯ２半导体催化剂表面的光催化还原受体系的酸度影响较大．Ｈ２ＰＯ４－阴离子或Ｍｎ２＋离子存在会降低Ｃｒ（ＶＩ）离子的光催化还原效率．在太阳光照下，Ｃｒ（ＶＩ）离子在ＴｉＯ２上的光催化还原也可实现．通过调节反应结束后水溶液的酸碱度，Ｃｒ（ＶＩ）离子得以消除．反应后催化剂经酸处理，其活性恢复并可重复使用．
With the increase of pH, the adsorption of Cr (VI) ions on TiO2 surface decreased. When the initial concentration of Cr (VI) ion is 300μmol / L, it has the maximum adsorption on the surface of TiO2. The presence of H2PO4- and acetic acid can inhibit the adsorption of Cr (VI) ions. The presence of formic acid increases the adsorption of Cr (VI) ions. The photocatalytic reduction of Cr (VI) ions on the surface of TiO2 semiconductor catalyst is greatly influenced by the acidity of the system. The presence of H2PO4- or Mn2 + ions reduces the photocatalytic reduction efficiency of Cr (VI) ions. Photocatalytic reduction of Cr (VI) ions on TiO2 can also be achieved under sunlight. Cr (VI) ions are eliminated by adjusting the pH of the aqueous solution after the reaction is completed. After the reaction of the catalyst by acid treatment, the activity recovery and reusable.