کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4485108 1316941 2007 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
A comparison of fenuron degradation by hydroxyl and carbonate radicals in aqueous solution
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات فرآیندهای سطح زمین
پیش نمایش صفحه اول مقاله
A comparison of fenuron degradation by hydroxyl and carbonate radicals in aqueous solution
چکیده انگلیسی

A comparative study of the transformation of the herbicide fenuron (1,1-dimethyl-3-phenylurea) by hydroxyl radicals and carbonate radicals in aqueous solution (pH 7.2-phosphate buffer) has been undertaken. Hydroxyl radical was generated by the well-known photolysis of hydrogen peroxide at 254 nm and carbonate radical was formed by photolysis of Co(NH3)5CO3+ at 254 nm. Competitive kinetic experiments were performed with atrazine used as the main competitor for both processes. Accordingly, the second-order rate constant of reaction between fenuron and carbonate radical was found to be (7−12±3)×106 M−1 s−1 [(7±1)×109 M−1 s−1 for hydroxyl radical]. The formation of degradation products was studied by LC-MS in the two cases and a comparison has been performed. The reaction with carbonate radical leads to the formation of a quinone-imine derivative which appears as the major primary product together with ortho and para hydroxylated compounds. These two compounds represent the major products in the reaction with hydroxyl radicals. The reaction of both radicals also leads to the transformation of the dimethylurea moiety.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Water Research - Volume 41, Issue 20, December 2007, Pages 4585–4594
نویسندگان
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