title: Photodegradation of bisphenol A in Fe(III)-oxalate complexes solution.
abstract: The aqueous photodegradation of bisphenol A (BPA) in the presence of Fe(III)-oxalate complexes (Fe(III)-Ox), which are common compositions of natural water, was investigated in this study. BPA underwent rapid indirect photolysis in Fe(III)-Ox solution under simulated solar irradiation, proceeding pseudo-first-order kinetics. The photolysis rate increased with decreasing pH or initial BPA level and increasing Fe(III)/oxalate concentration ratio. Hydroxyl radicals (*OH), which were generated from the photochemical processes of Fe(III)-Ox complexes and contributed to the photooxidation of BPA, were determined by molecular probe and electron spin resonance (ESR) methods with the steady-state concentration of 2.56 x 10(-14) mol/L. Superoxide anion radical (O2*-) was considered as the precursor of *OH and qualitatively determined by adding nitro blue tetrazolium as well as ESR experiments. Based on the structural analysis of the intermediate photoproducts of BPA in Fe(III)-Ox complexes solution, the possible degradation pathways of BPA were proposed, involving *OH addition, alkyl scission and alky oxidation. The results indicate that the photochemical reactivity of Fe(III) may affect the environmental fate of BPA in natural water significantly.
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, China.
authors.forename: Man-jun
authors.initials: MJ
authors.lastname: Zhan
authors.forename: Xi
authors.initials: X
authors.lastname: Yang
authors.forename: Qi-ming
authors.initials: QM
authors.lastname: Xian
authors.forename: Ling-ren
authors.initials: LR
authors.lastname: Kong
mesh_terms: D001559:Benzhydryl Compounds; D017665:Hydroxyl Radical / Q000737:chemistry; D007700:Kinetics; D010070:Oxalates / Q000737:chemistry*; D010636:Phenols / Q000737:chemistry* / Q000528:radiation effects*; D010782:Photolysis; D013472:Sunlight; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000528:radiation effects; D000098826:Bisphenol A Compounds
chemical_list: D001559:Benzhydryl Compounds; D017665:Hydroxyl Radical; D010070:Oxalates; D010636:Phenols; D014874:Water Pollutants, Chemical; C006780:bisphenol A; D000098826:Bisphenol A Compounds