title: Complete mineralization of perfluorooctanoic acid (PFOA) by γ-irradiation in aqueous solution.
abstract: Decomposition of perfluorooctanoic acid (C7F15COOH, PFOA) has been gaining increasing interests because it is a ubiquitous environmental contaminant and resistant to the most conventional treatment processes. In this work, the rapid and complete mineralization of PFOA and simultaneous defluorination were achieved by γ-ray irradiation with a (60)Co source. The degradation rate of PFOA by γ-ray irradiation would be high, and a pseudo-first-order kinetic rate constant of 0.67 h(-1) could be achieved in the N2 satured condition at pH 13.0. The experimental results and quantum chemical calculation confirmed that two radicals, i.e., hydroxyl radical (·OH) and aqueous electrons (eaq(-)), were responsible for the degradation of PFOA, while only either eaq(-) or ·OH might not be able to accomplish complete mineralization of PFOA. The synergistic effects of ·OH and eaq(-) involved in the cleavage of C-C and C-F bonds, and therefore complete mineralization of PFOA were achieved. The intermediate products were identified and the degradation pathway was also proposed. The results of this study may offer a useful, high-efficient approach for complete mineralizing fluorochemicals and other persistent pollutants.
authors.affiliation: CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry.
authors.forename: Ze
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry.
authors.forename: Jie-Jie
authors.initials: JJ
authors.lastname: Chen
authors.affiliation: CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry.
authors.forename: Xian-Jin
authors.initials: XJ
authors.lastname: Lyu
authors.affiliation: Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei, 230026, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Yin
authors.affiliation: CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry.
authors.forename: Guo-Ping
authors.initials: GP
authors.lastname: Sheng
mesh_terms: D002210:Caprylates / Q000737:chemistry*; D005466:Fluorocarbons / Q000737:chemistry*; D005720:Gamma Rays; D017665:Hydroxyl Radical / Q000737:chemistry*
chemical_list: D002210:Caprylates; D005466:Fluorocarbons; D017665:Hydroxyl Radical; C023036:perfluorooctanoic acid