紫外光降解饮用水中三氯乙腈的研究

摘要

为降解饮用水中的三氯乙腈(TCAN),采用紫外光(UV)降解TCAN.考察了紫外光强度、pH、TCAN初始浓度和温度对TCAN降解速率的影响.结果表明:随紫外光强度增加,拥有的光子会增加;pH增加,TCAN降解率逐步提高,偏碱性环境下由于TCAN会发生水解,再加上紫外光的作用,降解效率大幅提高;TCAN初始浓度增加,降解率逐步提高.温度对TCAN的降解率影响不明显.UV技术降解饮用水中TCAN的规律符合一级反应动力学,紫外灯光强度为110 μW/cm2的反应速率常数为0.00266.%In order to degrade the amounts of trichloroacetonitrile(TCAN)contained in drinking water,ultraviolet light has been used for its degradation.The influences of the UV intensity,pH,TCAN initial concentration and tem-perature on TCAN degradation rate have been investigated.The results show that the degradation rate of TCAN is in-creased gradually with the increase of photons,pH and UV light intensity.It can be improved greatly in sub-alkaline environment due to the hydrolysis of TCAN and the irradiation of UV.It can also be improved gradually with the in-crease of TCAN initial concentration.Temperature do not have obvious influence on TCAN degradation rate.The rule of UV technology for the degradation of TCAN in drinking water conforms to the first-order kinetics,and the reaction rate constant is 0.002 66 when UV intensity is 110 μW/cm2.