Son H S, Choi S B, Zoh K D, Khan E
Dept. of Environmental Health, School of Public Health, Seoul National University, Seoul 110-799, Korea.
Water Sci Technol. 2007;55(1-2):209-16. doi: 10.2166/wst.2007.034.
The effects of ultraviolet (UV) intensity and wavelength on triclosan (TCS) photodegradation kinetic, efficiency, mechanisms and pathway were studied. The TCS photodegradation followed the pseudo-first order kinetic model at all UV intensities examined at the wavelengths of 254 and 365 nm and the photodegradation rate increased with increasing UV intensity. TCS photodegradation efficiencies of 90 to 98% and 79 to 90% were obtained at the wavelengths of 254 and 365 nm, respectively. TCS was degraded mainly by photon induced hydroxyl radicals while the direct photon reaction with TCS played a subordinate role. Chlorophenol, dichlorophenol and phenol were the intermediates detected in all experiments conducted. Dibenzodichloro-p-dioxin and dibenzo-p-dioxin were observed as the intermediates only at lower UV intensities investigated at the wavelength of 365 nm. Based on these intermediates, a complete TCS photolysis pathway was proposed for the first time.
研究了紫外线（UV）强度和波长对三氯生（TCS）光降解动力学、效率、机制及途径的影响。在254和365 nm波长下所考察的所有UV强度下，TCS的光降解均遵循准一级动力学模型，且光降解速率随UV强度的增加而增大。在254和365 nm波长下，TCS的光降解效率分别为90%至98%和79%至90%。TCS主要通过光子诱导的羟基自由基降解，而与TCS的直接光子反应起次要作用。在所有实验中均检测到氯酚、二氯酚和苯酚为中间体。仅在365 nm波长下较低UV强度的研究中观察到二苯并二氯对二恶英和二苯并对二恶英为中间体。基于这些中间体，首次提出了完整的TCS光解途径。
