title: Chemical oxidation of sulfadiazine by the Fenton process: kinetics, pathways, toxicity evaluation.
abstract: This paper investigated sulfadiazine oxidation by the Fenton process under various reaction conditions. The reaction conditions tested in the experiments included the initial pH value of reaction solutions, and the dosages of ferrous ions and hydrogen peroxide. Under the reaction conditions with pH 3, 0.25 mM of ferrous ion and 2 mM of hydrogen peroxide, a removal efficiency of nearly 100% was achieved for sulfadiazine. A series of intermediate products including 4-OH-sulfadiazine/or 5-OH-sulfadiazine, 2-aminopyrimidine, sulfanilamide, formic acid, and oxalic acid were identified. Based on these products, the possible oxidation pathway of sulfadiazine by Fenton's reagent was proposed. The toxicity evaluation of reaction solutions showed increased antimicrobial effects following the Fenton oxidation process. The results from this study suggest that the Fenton oxidation process could remove sulfadiazine, but also increase solution toxicity due to the presence of more toxic products.
authors.affiliation: a Department of Chemistry and Chemical Engineering , Hunan University of Arts and Science , Changde , China.
authors.forename: Ji-Feng
authors.initials: JF
authors.lastname: Yang
authors.forename: Shi-Biao
authors.initials: SB
authors.lastname: Zhou
authors.forename: An-Guo
authors.initials: AG
authors.lastname: Xiao
authors.forename: Wen-Jun
authors.initials: WJ
authors.lastname: Li
authors.forename: Guang-Guo
authors.initials: GG
authors.lastname: Ying
mesh_terms: D004785:Environmental Pollutants / Q000737:chemistry / Q000633:toxicity; D004926:Escherichia coli / Q000187:drug effects / Q000254:growth & development; D005561:Formates / Q000737:chemistry; D006861:Hydrogen Peroxide / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007501:Iron; D007700:Kinetics; D019815:Oxalic Acid / Q000737:chemistry; D010084:Oxidation-Reduction; D011743:Pyrimidines / Q000737:chemistry; D013411:Sulfadiazine / Q000737:chemistry* / Q000633:toxicity*; D013424:Sulfanilamides / Q000737:chemistry; D018675:Toxicity Tests / Q000379:methods
chemical_list: D004785:Environmental Pollutants; C045076:Fenton's reagent; D005561:Formates; D011743:Pyrimidines; D013424:Sulfanilamides; D013411:Sulfadiazine; C030544:formic acid; C012180:2-aminopyrimidine; D019815:Oxalic Acid; D006861:Hydrogen Peroxide; D007501:Iron
keywords: Fenton's agent; Sulfadiazine; oxidation; pathway; toxicity evaluation