光助Fenton氧化法降解水中六氯苯的研究

Degradation of hexachlorobenzene in water by photo-Fenton oxidation

采用光助Fenton氧化法处理六氯苯模拟废水,考察了反应时间、Fe3+与H2O2摩尔比、Fenton试剂用量、初始pH、六氯苯初始浓度、光强对六氯苯降解效果的影响,并初步探讨了六氯苯的降解动力学规律。结果表明,光助Fenton法降解六氯苯的最佳工艺条件为:紫外灯功率为300 W、Fe3+投加量为1.0 mmol/L、H2O2投加量为5.0 mmol/L、反应时间为60 min、初始pH为3,在此条件下,浓度为500μg/L的HCB的去除率可达91.3%。UV辐射与Fenton氧化对HCB的降解具有协同效应。光助Fenton法对HCB的降解符合一级反应动力学方程,表观速率常数为0.04 min-1,与Fenton法相比,提高了近9倍。

Hexachlorobenzene （HCB） in water was degraded by photo-Fenton oxidation. Effects of reaction time, mole ratio of Fe3＋ to H2O2, Fenton reagent dosage, initial pH, HCB concentration and light intensity on removal efficiency of HCB were investigated. Kinetics for degradation of HCB was initially discussed, too. The optimal conditions were as following： the power of UV lamp is 300 W, Fe3＋ concentration is 1.0 mmol/L, H2O2 concentration is 5.0 mmol/L, and reaction time is 60 min, [ Fe3＋ ]： [ H2O2 ] is 1：5, initial pH is 3.0. Under the optimal conditions, the removal rate of HCB with 500μg/L of concentration can reach 91.3%. The synergistic effect of UV light and Fenton reagent is significant. The kinetics for degradation of HCB by UV/Fenton oxidation conforms to pseudo first-order reaction equation. The reaction rate constant of degradation of HCB by UV/ Fenton oxidation is 0.04 min-1 which is 9 times larger than that only by Fenton oxidation.