학술논문

Photocatalytic degradation of carbofuran in TiO2 aqueous solution: Kinetics using design of experiments and mechanism by HPLC/MS/MS.
Document Type
Article
Source
Journal of Environmental Sciences (Elsevier). Aug2013, Vol. 25 Issue 8, p1680-1686. 7p.
Subject
*PHOTOCATALYSIS
*CARBOFURAN
*TITANIUM dioxide
*AQUEOUS solutions
*HIGH performance liquid chromatography
*HYDROXYL group
*MASS spectrometry
Language
ISSN
1001-0742
Abstract
The photocatalytic degradation kinetics of carbofuran was optimized by central composite design based on response surface methodology for the first time. Three variables, TiO 2 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 TiO 2 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. [ABSTRACT FROM AUTHOR]