乙草胺在水溶液中的光降解研究

Photodegradation of Acetochlor in Aqueous Solution

【目的】通过研究乙草胺在水溶液中的光降解反应,为有效去除水体中的乙草胺提供理论依据。【方法】采用高效液相色谱对乙草胺水溶液(不添加任何试剂、添加H_2O_2、添加H_2O_2/Fe^(2+))在氙灯和汞灯照射条件下的降解行为进行研究。【结果】10mg/L乙草胺在氙灯照射600 min后降解了95.33%,在汞灯照射10 min后降解了95.15%;在氙灯照射240 min后,不添加任何试剂、添加H_2O_2和添加H_2O_2/Fe^(2+)的乙草胺分别降解了70.61%、84.28%和92.16%。【结论】乙草胺在水溶液中的光降解属于一级动力学反应,光降解速率次序为汞灯>氙灯+H_2O_2/Fe^(2+)>氙灯+H_2O_2>氙灯,且乙草胺添加H_2O_2、添加H_2O_2/Fe^(2+)与不添加任何试剂所产生的降解产物不同。

【Objective】In order to provide a good theoretical basis for the degradation of acetochlor in water,the photodegradation of acetochlor in aqueous solution was investigated.【Method】The degradation of acetochlor in aqueous solution（without additive,with H_2O_2,with H_2O_2/Fe^（2＋））under xenon lampand mercury lamp radiation were investigated using high performance liquid chromatography（HPLC）.【Result】The degradation rates of acetochlor at the initial concentration of 10 mg/L were 95.33%and 95.15%under the radiation of xenon lamp for 600 min and mercury lamp for 10 min,respectively.Under xenon lamp radiation for 240 min,the degradation rates were 70.61%,84.28%and 92.61%without additive,with H_2O_2and with H_2O_2/Fe^（2＋）,respectively.【Conclusion】The photodegradation process of acetochlor under the four conditions conformed to the first order kinetics.The photolysis rate of acetochlor in aqueous solution was in the order of mercury lampxenon lamp with H_2O_2/Fe^（2＋）xenon lamp with H_2O_2xenon lamp,and the degradation products with H_2O_2and with H_2O_2/Fe^（2＋）were different from that without additive under light radiation.