乙草胺和丁草胺的水解及其动力学

本文研究了乙草胺和丁草肢在恒温２５℃,ｐＨ值为４,７,１０蒸馏水和河水中的水解动力学．酰胺类除草剂的水解反应属于一级反应．结果显示乙草胺和丁草胺在蒸馏水和河水中的水解速度差不多,在ｐＨ ４水溶液中的水解速度较在ｐＨ７和１０的速度快,Ｈ＋有催化水解的作用．乙草胺在ｐＨ４,７,１０的速率常数分别为５×ｌ０－４ｄ－１,３×１０－４ｄ－１,３×１０－４ｄ－１．半衰期分别为１３８６ｄ,２３ｌ０ｄ,２３１０ｄ．丁草胺在ｐＨ４,７,１０的速率常数分别为 ｌ．１× １０－３ｄ－１,６ × １０－４ｄ－１,６ × １０－４ｄ－１．半衰期分别为 ６３０ｄ,１１５５ｄ,１１５５ｄ．

HYDROLYSIS OF CHLOROACETANILIDE HERBICIDESACETOCHLOR AND BUTACHLOR

The hydrolysis of acetochlor and butachlor in distilled and river water was studied by incubation at 25℃and HPLC analysis in the paper.The kinetics process of acetochlor and butachlor can be described by the fist-order reaction law.The experimental results indicated that the hydrolysis rates of acetochlor or butachlor in distilled and river water were almost same.H＋ can accelerate acetochlor and butachlor hydrolysis.The hydrolysis rate of acetochlor or butachlor in pH 4 water was faster than in pH 7 or pH 10 water.The rate constants k of acetochlor hydrolysis in different pH 4,pH 7 and pH 10 water were 5×10－4d－1，3×10－4d－1 and 3×10－4d－1 respectively.The half-life of acetochlor hydrolysis in different pH 4,pH 7 and pH 10 water were 1386,2310 and 2310 days.The rate constants k of butachlor hydrolysis in different pH 4,pH 7 and pH 10 water were 1.1×10－3d－1，6×10－4d－1and 6×10－4d－1 respectively.The half-life of butachlor hydrolysis in different pH 4,pH 7 and pH 10 water were 630,1155 and 1155 days.