Department of Civil and Environmental Engineering, Virginia Polytechnic Institute and State University, VA 24061, USA.
Water Res. 2011 Apr;45(8):2507-16. doi: 10.1016/j.watres.2011.02.006. Epub 2011 Feb 12.
Advanced treatment technologies that control multiple contaminants are beneficial to drinking water treatment. This research applied UV/H(2)O(2) for the simultaneous degradation of geosmin, 2-methylisoborneol, four trihalomethanes and six haloacetic acids. Experiments were conducted in de-ionized water at 24 ± 1.0 °C with ng/L amounts of odorants and μg/L amounts of disinfection byproducts. UV was applied with and without 6 mg/L H(2)O(2.) The results demonstrated that brominated trihalomethanes and brominated haloacetic acids were degraded to a greater extent than geosmin and 2-methylisoborneol. Tribromomethane and dibromochloromethane were degraded by 99% and 80% respectively at the UV dose of 1200 mJ/cm(2) with 6 mg/L H(2)O(2), whereas 90% of the geosmin and 60% of the 2-methylisoborneol were removed. Tribromoacetic acid and dibromoacetic acid were degraded by 99% and 80% respectively under the same conditions. Concentrations of trichloromethane and chlorinated haloacetic acids were not substantially reduced under these conditions and were not effectively removed at doses designed to remove geosmin and 2-methylisoborneol. Brominated compounds were degraded primarily by direct photolysis and cleavage of the C-Br bond with pseudo first order rate constants ranging from 10(-3) to 10(-2) s(-1). Geosmin and 2-methylisoborneol were primarily degraded by reaction with hydroxyl radical with direct photolysis as a minor factor. Perchlorinated disinfection byproducts were degraded by reaction with hydroxyl radicals. These results indicate that the UV/H(2)O(2) can be applied to effectively control both odorants and brominated disinfection byproducts.
高级处理技术可同时控制多种污染物，有利于饮用水处理。本研究采用 UV/H2O2 同时降解土臭素、2-甲基异莰醇、四种三卤甲烷和六种卤乙酸。实验在 24 ± 1.0°C 的去离子水中进行，水样中含痕量的嗅味物质和μg/L 级的消毒副产物。UV 处理时投加或不投加 6mg/L 的 H2O2。结果表明，溴代三卤甲烷和溴代卤乙酸比土臭素和 2-甲基异莰醇更易降解。三溴甲烷和二溴一氯甲烷在 1200mJ/cm2UV 剂量和 6mg/L H2O2 条件下分别降解 99%和 80%，而土臭素和 2-甲基异莰醇分别去除 90%和 60%。三溴乙酸和二溴乙酸在相同条件下分别降解 99%和 80%。三氯甲烷和氯化卤乙酸的浓度在这些条件下没有明显降低，并且在设计去除土臭素和 2-甲基异莰醇的剂量下也不能有效去除。溴代化合物主要通过直接光解和 C-Br 键的断裂降解，其假一级速率常数范围为 10(-3)至 10(-2)s(-1)。土臭素和 2-甲基异莰醇主要通过与羟基自由基反应降解，直接光解为次要因素。高氯消毒副产物通过与羟基自由基反应降解。结果表明，UV/H2O2 可有效控制嗅味物质和溴代消毒副产物。
