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Triclocarban is a common antimicrobial and antibanterial agent found in many personalcare products, including medical disinfectant, detergent, soap, mouthwash, toothpastes,shampoo. Reacently, it is attracting much attention that the usage of TCC is increasingsignificantly with the development of the chemical industry and the population growing. TCCis chemically stable and difficult to degrade, so it may cause environmental problem for longstay.In this article, it investigated the effectiveness of three different system on the TCCdegradation, as ultraviolet （UV） radiation, simulated sunlight, and UV/S2O82-. Underultraviolet （UV） radiation and simulated sunlight station, the main propose is to find theregularity of the TCC degradation and its influencing factors to provide data for the furtherstudy. The UV/S2O82-system is to find a way for the efficient and complete degradation ofTCC. The contents and results are as follows:（1） UV radiation: we investigated the effects of several operational parameters, includingpH value, initial TCC concentration, photocatalyst TiO2loading, presence of natural organicmatter, and most common anions in surface waters（e.g., bicarbonate, nitrate, and sulfate）. Theresults showed that UV radiation was very effective for TCC photodegradation, thedegradation rate could got100%in10mins, and the photolsis followed pseudo-first-orderkinetics. The TCC photolysis rate is much higher under low initial TCC concentration thanhigh concentration. The TCC degradation is favored at alkaline condition. A higher TCCphotolysis rate was observed by direct photolysis than TiO2photocatalysis. The presence ofthe inorganic ions bicarbone, nitrate, and sulfate hindered TCC photolysis. Furthermore,based on the results of GC/MS, four mian intermediates were indentified:3,4-dichloroaniline,4-chloroaniline,4-chloroisocyanatobenzene, and4-chloronitrobenzene. Furthermore, afteradding isopropanol and benzoquinone respectively to the solution, we found that O2· playedamajor role in the TCC degradation.（2） simulated sunlight：under this system we choose xenon lamp as light source, andinvestigated sevral paramters of effect, such as initial pH value, inorganic ions （HCO3,NO3-,and Cl-）,humic acid and humic acid sodium on the TCC degradation.（3） UV/S2O82-: persulfate oxidation is hot issue for its powerful oxidation andenvironment-friendly property. Compared with UV radiation longly, UV/S2O82-can be mucheffectively for TCC degradation, and the decomposition of TCC followed a first-order kinetics behavior. Under UV/S2O82-system, the TCC degradation rate increased with theinitial S2O82-concentration increase, and the weak alkaline is favorable for the TCCdecomposition. The presence of HCO3-have no effect on the reaction, and the H2PO4-caninhibit it. Low concentration Cl-had positive effect and high concentration Cl-had negativeeffect. Similar with the UV radation, the presence of HA had a negative effect on TCCdegradation.
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