O3/H2O2降解水中速灭威的试验研究  

Study on Degradation of Metolcarb by O3/H2O2

作　　者：郝凤霞[1] 何金兰 李鹏[1] 夏维涛 杨金会[1] HAO Fengxia;HE Jinlan;LI Peng;XIA Weitao;YANG Jinhui(State Key Laboratory of High-efficiency Utilization of Coal&Green Chemical Engineering,Ning Xia University,Yinchuan 750021,China)

机构地区：[1]宁夏大学省部共建煤炭高效利用与绿色化工国家重点实验室

出　　处：《环境科学与技术》2019年第9期152-155,共4页Environmental Science & Technology

基　　金：国家自然科学基金项目（21567022）

摘　　要：速灭威是枸杞中常用的一种氨基甲酸酯类农药,在防治枸杞蚜虫的同时,残留在土壤中的速灭威又会经淋溶作用渗透到地下水中,对地下水造成严重的威胁。文章采用臭氧发生器对臭氧/双氧水(O3/H2O2)降解水中速灭威进行了试验研究,考察了O3流量、pH、氧化时间等因素对速灭威降解率的影响,并采用气相色谱与质谱联用仪(GC-MS)对降解后的产物进行分析,探讨O3/H2O2降解速灭威可能的反应机理。结果表明:(1)pH为6时,降解率最大,为44%,而在中性条件下降解率最低;(2)随着臭氧流速的增加,速灭威的降解率也逐步增加,当臭氧流速为0.6 L/min时速灭威全部降解;(3)随着时间的延长,速灭威的降解率逐渐增加,其中,在1 h内降解迅速,2 h时速灭威已经100%降解;(4)降解得到的中间产物主要有间甲基苯酚等,据此推断降解机理可能是·OH自由基断裂醚键,推导了O3/H2O2氧化速灭威可能的降解途径。Metolcarb, a kind of carbamate pesticide commonly used in controlling of Aphis sp, is liable to incur pollution risk when its remainder in soil leached into groundwater. In this paper, degradation of metolcarb in water solution was studied using the combination of ozone hydrogen peroxide;effects of ozone currents, pH values and temperatures on the oxidation of metolcarb were tested;the main degradation products were identified by GC-MS;and the probable mechanism and pathway of the oxidation of metolcarb by ozone hydrogen peroxide were discussed. The result of the laboratory study revealed:(1)when the solution at pH 6, the degradation rate was the highest(44%), while the degradation rate was the lowest when the solution was neutral;(2) as the ozone currents increased, so did the degradation rate of metolcarb gradually, and when the ozone current attained 0.6 L/min, degradation rate of metolcarb is completely degraded and wiped out;(3) with the extension of time, the degradation rate increased gradually, and growing rapidly at 1 h;furthermore, the degradation rate reached 100% at 2 h;and(4) the main of degradation products identified were m-Cresol, etc;accordingly, the degradation mechanism could be explicated by the breaking-up of ether bond by OH free radicals, and based on which, the possible degradation pathway of degradation of metolcarb by combination of ozone hydrogen peroxide could be deduced.

关 键 词：O3/H2O2 速灭威 降解 GC-MS 机制 

分 类 号：X592[环境科学与工程—环境工程]