title: [Photo-chemical decomposition of perfluorooctanoic acids in aqueous periodate].
abstract: The influence of reaction atmosphere and TiO2 on photochemical decomposition of perfluorooctanoic acid (PFOA) in aqueous periodate was investigated using a type of low-pressure mercury lamps emitted at 254 nm. PFOA photolysis was slight with 254 nm light irradiation under nitrogen, whereas significant decomposition PFOA obtained with the addition of IO4-. In addition, oxygen restrained photochemical decomposition of PFOA. In UV/TiO2/IO4- system, PFOA degradation ratio was 54%, 15% lower than that for UV/IO4- system. *OH radicals generated from UV/TiO2 system exhausted a lot of IO4-, resulting in lower degree of IO3* production. IO3* was high reactive radical which great excitated PFOA decomposition. The accumulation of short-chain perfluorocarbonxylic acids (PFCAs) as products were identified with HPLC/MS. PFCAs bearing shorter perfluoroalkyl groups were formed in a stepwise way from PFCAs that bear longer perfluoroalkyl groups.
authors.affiliation: College of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China. cmh850513@163.com
authors.forename: Meng-Hua
authors.initials: MH
authors.lastname: Cao
authors.forename: Bei-Bei
authors.initials: BB
authors.lastname: Wang
authors.forename: Hu-Di
authors.initials: HD
authors.lastname: Zhu
authors.forename: Zhen-Ji
authors.initials: ZJ
authors.lastname: Tan
authors.forename: You-Shi
authors.initials: YS
authors.lastname: Zeng
authors.forename: Lin-Ling
authors.initials: LL
authors.lastname: Wang
authors.forename: Song-Hu
authors.initials: SH
authors.lastname: Yuan
authors.forename: Jing
authors.initials: J
authors.lastname: Chen
mesh_terms: D002210:Caprylates / Q000737:chemistry / Q000302:isolation & purification*; D005466:Fluorocarbons / Q000737:chemistry / Q000302:isolation & purification*; D010084:Oxidation-Reduction; D010504:Periodic Acid / Q000737:chemistry*; D055668:Photochemical Processes; D014025:Titanium / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000302:isolation & purification*
chemical_list: D002210:Caprylates; D005466:Fluorocarbons; D014874:Water Pollutants, Chemical; D010504:Periodic Acid; C009495:titanium dioxide; C023036:perfluorooctanoic acid; C009288:metaperiodate; D014025:Titanium