二氧化钛光催化还原Cr(Ⅵ)的研究

Study on TiO_2 Photocatalysis Reduction of Cr(Ⅵ)

用自制二氧化钛粉末光催化剂成功地处理了含Cr(Ⅵ)废水。提出了Cr(Ⅵ)光致还原的最佳条件,确立了当溶液酸度为0.5mol/LH2SO4,Cr(Ⅵ)质量浓度为80mg/L的50mL废水,催化剂用量为0.3g,光照时间4.0h时,Cr(Ⅵ)的光致还原率达95.0 %以上。同时对光催化转化Cr(Ⅵ)的机理进行了初步探讨,证明Cr(Ⅵ)的TiO2 光致还原遵循一级反应速率公式:lnC= -0.88t +4.38。

The waste water including Cr(Ⅵ) has been handled by photocatalyst-the powder of TiO2. The optimum photo reduction conditions are as follows: the acidity of the aqueous solution is 0.5 mol/L H2SO4, the mass concentration of Cr(Ⅵ) is 80 mg/L and its volume is 50 mL, the quantity of catalyst is 0.3 g, the time of photo radiation is 4.0 h, the photo reduction ratio of Cr(Ⅵ) is over 95.0%. At the same time, the mechanism of photocatalytic conversion of Cr(Ⅵ) has been preliminarily probed, and it is proved that TiO2 photo reduction of Cr(Ⅵ) follows the formula of one-order reaction rate:lnC=-0.88t+4.38.