title: In situ study of the photodegradation of carbofuran deposited on TiO2 film under UV light, using ATR-FTIR coupled to HS-MCR-ALS.
abstract: The in situ study of the photodegradation of carbofuran deposited on a TiO2 catalyst film under UV light was carried out using the ATR-FTIR technique. The data were analyzed using a Hard-Soft Multivariate Curve Resolution-Alternating Least Squares (HS-MCR-ALS) methodology. Using S-MCR-ALS, four factors were deduced from the evolving factor analysis of the data, and their concentrations and spectra were determined. These results were used to draw qualitative and quantitative analyses of the major products of carbofuran photodegradation. The results of this analysis were in good agreement with GC-MS results and with reported mechanisms. Hard-MCR-ALS was then used to refine the spectra and concentrations, using a multistep kinetic model. The rate constant for the first step in the photodegradation of carbofuran was found to be 2.9 × 10(-3) min(-1). The higher magnitude of the correlation (96.87%), the explained variance (99.87%) and LOF (3.01), are good indicators of the reliability of the outcome of this approach. This method has been shown to be an efficient approach to study in situ photodegradation of pesticides on a solid surface.
authors.affiliation: Chemistry Department, Marquette University , P.O. Box 1881, Milwaukee, Wisconsin 53201, United States.
authors.forename: Abderrahman
authors.initials: A
authors.lastname: Atifi
authors.forename: Kazimierz
authors.initials: K
authors.lastname: Czarnecki
authors.forename: Hafida
authors.initials: H
authors.lastname: Mountacer
authors.forename: Michael D
authors.initials: MD
authors.lastname: Ryan
mesh_terms: D002235:Carbofuran / Q000737:chemistry*; D016018:Least-Squares Analysis; D015999:Multivariate Analysis; D055668:Photochemical Processes; D011789:Quantum Theory; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods*; D014025:Titanium / Q000737:chemistry*; D014466:Ultraviolet Rays
chemical_list: C009495:titanium dioxide; D014025:Titanium; D002235:Carbofuran