| Abstract
| - A modified Fenton reagent (Fe3+/H2O2) transformed the fungicide chlorothalonil within 60 min inaqueous solution at unadjusted pH. Transformation varied with ferric salt. Transformation was greatestwith ferric nitrate and least when ferric sulfate was used. UV irradiation enhanced the transformationof chlorothalonil. The transformation of chlorothalonil was enhanced, which increased with ferric ionor hydrogen peroxide concentration. Maximum transformation was achieved at 2 mM ferric ion and100 mM hydrogen peroxide. Additionally, chlorothalonil was more dechlorinated in the UV irradiationcondition. The proposed reaction pathway includes reduction of chlorothalonil to trichloroisophthalonitrile, dichloroisophthalonitrile, and monochloroisophthalonitrile; oxidation of trichloroisophthalonitrileto trichloro-3-cyanobenzoic acid and 3-carbamyltrichlorobenzoic acid; and oxidation of hydroxychlorothalonil to trichloro-3-cyanohydroxybenzoic acid and trichlorocyanophenol. Keywords: Chlorothalonil, Fenton reagent, transformation, UV irradiation
|
