Song Shuang, Xu Lejin, He Zhiqiao, Ying Haiping, Chen Jianmeng, Xiao Xiuzhen, Yan Bing
College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, People's Republic of China.
J Hazard Mater. 2008 Apr 15;152(3):1301-8. doi: 10.1016/j.jhazmat.2007.08.004. Epub 2007 Aug 6.
The photocatalytic degradation of C.I. Direct Red 23 (4BS) in aqueous solutions under UV irradiation was investigated with SrTiO3/CeO2 composite as the catalyst. The SrTiO3/CeO2 powders had more photocatalytic activity for decolorization of 4BS than that of pure SrTiO3 powder under UV irradiation. The effects of catalytic dose, pH value, initial concentration of dye, irradiation intensity as well as scavenger KI were ascertained, and the optimum conditions for maximum degradation were determined. Under the irradiation of a 250 W mercury lamp, the best catalytic dose was 1.5 g/L and the best pH was 12.0. Light intensity exhibited a significant positive effect on the efficiency of decolorization, whereas the initial dye concentration showed a significant negative effect. Under the conditions of a catalytic dose of 1.5 g/L, pH of 12.0, initial dye concentration of 100mg/L, light intensity of 250 W, and air flow rate of 0.15 m3/h, complete decolorization, as determined by UV-visible analysis, was achieved in 60 min, corresponding to a reduction in chemical oxygen demand (COD) of 69% after a 240 min reaction. A tentative degradation pathway based on the sensitization mechanism of photocatalysis is proposed.
以SrTiO₃/CeO₂复合材料为催化剂，研究了紫外光照射下水中C.I.直接红23（4BS）的光催化降解。在紫外光照射下，SrTiO₃/CeO₂粉末对4BS脱色的光催化活性比纯SrTiO₃粉末更高。确定了催化剂量、pH值、染料初始浓度、照射强度以及清除剂KI的影响，并确定了最大降解的最佳条件。在250W汞灯照射下，最佳催化剂量为1.5g/L，最佳pH值为12.0。光强度对脱色效率有显著的正向影响，而染料初始浓度则有显著的负向影响。在催化剂量为1.5g/L、pH值为12.0、染料初始浓度为100mg/L、光强度为250W、空气流速为0.15m³/h的条件下，通过紫外-可见分析确定，60分钟内实现了完全脱色，240分钟反应后化学需氧量（COD）降低了69%。提出了一种基于光催化敏化机理的初步降解途径。
