School of Chemistry and Environment, South China Normal University, Guangzhou, Guangdong, PR China.
J Hazard Mater. 2011 Jul 15;191(1-3):136-43. doi: 10.1016/j.jhazmat.2011.04.059. Epub 2011 Apr 21.
Photocatalytic degradation of phenanthrene (PHE) over TiO(2) in aqueous solution containing nonionic surfactant micelles was investigated. All photocatalytic experiments were conducted using a 253.7 nm mercury monochromatic ultraviolet lamp in a photocatalytic reactor. The surfactant micelles could provide a nonaqueous "cage" to result in a higher degradation rate of PHE than in an aqueous solution, but the higher Triton X-100 concentration (more than 2 g/L) lowered the degradation ratio of PHE because the additional surfactant micelles hindered the movement of micelles containing PHE so as to reduce their adsorption onto titania. Pseudo-second-order kinetics was observed for the photocatalytic degradation of PHE. Alkaline solution environment was beneficial to the photocatalytic degradation of PHE. PHE degradation could mainly be attributed to the formation of hydroxyl radicals as evident from the comparison of degradation efficiencies when O(2), H(2)O(2) and tert-butyl alcohol (TBA) were applied as oxidants or hydroxyl radical scavenger. Based on the GC/MS analysis of the intermediates, the possible pathways of the photocatalytic degradation of PHE were proposed.
在含有非离子表面活性剂胶束的水溶液中，用 TiO2 光催化降解菲（PHE）。所有的光催化实验都是在光催化反应器中使用 253.7nm 汞单色紫外灯进行的。表面活性剂胶束可以提供一个非水“笼”，导致 PHE 的降解率高于水溶液，但更高的 Triton X-100 浓度（超过 2g/L）降低了 PHE 的降解率，因为额外的表面活性剂胶束阻碍了含有 PHE 的胶束的运动，从而减少了它们对二氧化钛的吸附。PHE 的光催化降解符合准二级动力学。碱性溶液环境有利于 PHE 的光催化降解。从比较当 O2、H2O2 和叔丁醇（TBA）作为氧化剂或羟基自由基清除剂时的降解效率，可以看出，菲的降解主要归因于羟基自由基的形成。基于对中间产物的 GC/MS 分析，提出了 PHE 光催化降解的可能途径。
