杀菌剂百菌清被芬顿试剂的转化作用。

Transformation of the fungicide chlorothalonil by Fenton reagent.

作者信息

Park Jong-Woo, Lee Sung-Eun, Rhee In-Koo, Kim Jang-Eok

机构信息

Department of Agricultural Chemistry, Kyungpook National University, 1370, Sankyuk dong, Buk-gu, Daegu 702-701, Korea.

出版信息

J Agric Food Chem. 2002 Dec 18;50(26):7570-5. doi: 10.1021/jf025772o.

DOI:10.1021/jf025772o

PMID:12475272

Abstract

A modified Fenton reagent (Fe(3+)/H(2)O(2)) transformed the fungicide chlorothalonil within 60 min in aqueous solution at unadjusted pH. Transformation varied with ferric salt. Transformation was greatest with ferric nitrate and least when ferric sulfate was used. UV irradiation enhanced the transformation of chlorothalonil. The transformation of chlorothalonil was enhanced, which increased with ferric ion or hydrogen peroxide concentration. Maximum transformation was achieved at 2 mM ferric ion and 100 mM hydrogen peroxide. Additionally, chlorothalonil was more dechlorinated in the UV irradiation condition. The proposed reaction pathway includes reduction of chlorothalonil to trichloroisophthalonitrile, dichloroisophthalonitrile, and monochloroisophthalonitrile; oxidation of trichloroisophthalonitrile to trichloro-3-cyanobenzoic acid and 3-carbamyltrichlorobenzoic acid; and oxidation of hydroxychlorothalonil to trichloro-3-cyanohydroxybenzoic acid and trichlorocyanophenol.

摘要

一种改良的芬顿试剂（Fe(3+)/H(2)O(2)）在未调节pH值的水溶液中60分钟内就能转化杀菌剂百菌清。转化情况因铁盐而异。使用硝酸铁时转化程度最大，而使用硫酸铁时转化程度最小。紫外线照射增强了百菌清的转化。百菌清的转化得到增强，且随着铁离子或过氧化氢浓度的增加而增加。在铁离子浓度为2 mM和过氧化氢浓度为100 mM时实现了最大转化。此外，在紫外线照射条件下百菌清的脱氯作用更强。所提出的反应途径包括将百菌清还原为三氯异苯腈、二氯异苯腈和一氯异苯腈；将三氯异苯腈氧化为三氯-3-氰基苯甲酸和3-氨甲酰基三氯苯甲酸；以及将羟基百菌清氧化为三氯-3-氰基羟基苯甲酸和三氯氰基苯酚。