O3/H2O2降解阿特拉津影响因素研究

Impacts of reactive factors on atrazine degradation by O_3/H_2O_2

摘要采用O3/H2O2，氧化去除水中内分泌干扰物阿特拉津，考察了反应条件及水质对去除的影响，并对反应机制进行了初步探讨。阿特拉津初始浓度2mg/L，投量为7．5mg/L的O3，单独氧化去除率为27．2％；相同O3投量下，控制H2O2/O，摩尔比为0．75，5min阿特拉津的去除率最高可达96．5％；pH值为7．5～8．5，温度在25～40℃的范围内，都维持了较高的去除率，表明H2O2/O3，体系对阿特拉津的去除效果良好，降解速度快，反应条件温和。0．5mg/L的腐殖酸，对阿特拉津的去除影响不大，腐殖酸浓度为1、2和5mg/L时，平均去除率分别为63．4％、50．7％和30．2％；碳酸氢钠的浓度为50和200mg/L时，去除率分别为88．1％和73．8％，说明水质对阿特拉津的去除影响较大。叔丁醇的浓度为5和20mg/L时，阿特拉津的去除率分别降低到44．7％和27．5％，去除率随自由基抑制剂叔丁醇增加而降低，说明H2O2/O3降解阿特拉津主要为该体系产生的羟基自由基的贡献。

The impacts of reactive influencing factors and water quality on the degradation of the representative endocrine disrupter atrazine by 3/HO2 were studied and the reactive mechanism was discussed briefly in this paper. The initial content of atrazine 2 mg/L was removed about 96. 5% in 5 min by O3/H2O2 system when the 03 was dosed as 2 mg/L and the H2O2/O3 molar ratios was 0.75, whereas the removal efficiency was just 27.2% by 03 alone. The removal efficiency was maintained 90% above when pH was 7.5 - 8.5 and the temperature was 25 -40℃ , which showed atrazine could be oxidzed effectively and rapidly by H2O2/O3 system in ordinary reactive condition. The removal of atrazine was not affected by low content of humic acid, but the removal efficiency were cut down to 63.4% ,50. 7% and 30. 2% when the humic acid doses were 1 mg/L, 2 mg/L and 5 mg/L. Simultaneously, the removal efficiency were 88.1% and 73.8% when the contents of hydrogen carbonate sodium were 50 mg/L and 200 mg/L. Both these indicated the removal efficiency was influenced greatly by water quality. When the contents of teabutyl alcohol were 5 mg/L and 20 mg/L, the removal efficiency were 44.7% and 27.5% respectively. The removal efficiency of atrazine declined along with the increasing of the hydroxyl free radical inhibitor which suggested the breakage of atrazine chemical structure might own to hydroxyl free radical produced by H2O2/O3 system.