title: Photocatalytic degradation of carbofuran in TiO2 aqueous solution: kinetics using design of experiments and mechanism by HPLC/MS/MS.
abstract: The photocatalytic degradation kinetics of carbofuran was optimized by central composite design based on response surface methodology for the first time. Three variables, TiO2 concentration, initial pH value and the concentration of carbofuran, were selected to determine the dependence of degradation efficiencies on independent variables. Response surface methodology modeling results indicated that the degradation efficiency of carbofuran was highly affected by the initial pH value and the concentration of carbofuran. Then nine degradation intermediates were detected by HPLC/MS/MS. The Frontier Electron Densities of carbofuran were calculated to predict the active sites on carbofuran attacked by hydroxyl radicals and photoholes. Point charges were used to elucidate the chemisorption pattern on TiO2 catalysts during the photocatalytic process. By combining the experimental results and calculation data, the photocatalytic degradation pathways of carbofuran were proposed, including the addition of hydroxyl radicals and the cleavage of the carbamate side chain.
authors: College of Chemistry and Chemical Engineering, Hunan Institute of Engineering, Xiangtan 411104, China. yanghai1001@163.com
authors: Hai
authors: H
authors: Yang
authors: College of Chemistry and Chemical Engineering, Hunan Institute of Engineering, Xiangtan 411104, China.
authors: Shuolin
authors: S
authors: Zhou
authors: College of Chemistry and Chemical Engineering, Hunan Institute of Engineering, Xiangtan 411104, China.
authors: Huajie
authors: H
authors: Liu
authors: College of Chemistry and Chemical Engineering, Hunan Institute of Engineering, Xiangtan 411104, China.
authors: Weiwei
authors: W
authors: Yan
authors: South China Institute of Environmental Sciences, Ministry of Environmental Protection, Guangzhou 510655, China.
authors: Liping
authors: L
authors: Yang
authors: College of Chemistry and Chemical Engineering, Hunan Institute of Engineering, Xiangtan 411104, China.
authors: Bing
authors: B
authors: Yij
mesh_terms: D002235:Carbofuran / Q000737:chemistry*; D002384:Catalysis; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D007306:Insecticides / Q000737:chemistry*; D007700:Kinetics; D055668:Photochemical Processes; D012996:Solutions; D053719:Tandem Mass Spectrometry / Q000379:methods*; D014025:Titanium / Q000737:chemistry*; D014867:Water
chemical_list: D007306:Insecticides; D012996:Solutions; D014867:Water; C009495:titanium dioxide; D014025:Titanium; D002235:Carbofuran