期刊
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
卷 48, 期 3, 页码 944-950出版社
AMER CHEMICAL SOC
DOI: 10.1021/jf990618w
关键词
chloroacetanilide; herbicide; monochloroacetic acid; photolysis
The photolysis of metolachlor [2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl) acetamide] in a sunlight simulator under actinic radiation was investigated. The focus of the study was to determine the extent of monochloroacetic acid (MCA) production. MCA was concentrated and derivatized from photolysate as the n-propyl ester using propanol and sulfuric acid and then identified as the ester using GC/MS and GC/ECD. On the basis of regression analysis, it was shown that the direct photodegradation of similar to 10 mu M metolachlor followed pseudo-first-order kinetics with respect to the metolachlor concentration, and the half-life of the herbicide (similar to 74 h) was independent of the pH of the medium. Photolysis in synthetic held water (SFW) resulted in a significant reduction of photolysis time (t(1/2) similar to 9 h). Direct photolysis experiments indicate a 5.19 +/- 0.81% (n=3) conversion of metolachlor to MCA, while photolysis in synthetic field water and in a Don River water sample resulted in 29.8 +/- 4.6% (n = 3) and 12.6 +/- 4.1% (n = 3) conversion, respectively; MCA was shown to be hydrolytically stable over the time course of the photoreaction. The photodegradation of alachlor, butachlor and a model chloroacetanilide, 2-chloro-N-methylacetanilide, in SFW were also investigated.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据