title: Persulfate-induced photochemical decomposition of a fluorotelomer unsaturated carboxylic acid in water.
abstract: The persulfate (S(2)O(8)(2-))-induced photochemical decomposition of C(3)F(7)CF=CHCOOH in water was investigated to develop a method to neutralize stationary sources of fluorotelomer unsaturated carboxylic acids (FTUCAs), which have recently been detected in the environment, and are considered to be more toxic than the environmentally persistent perfluorocarboxylic acids (PFCAs). Photolysis of S(2)O(8)(2-) produced highly oxidative sulfate radical anions (SO(4)(-)), which efficiently decomposed C(3)F(7)CF=CHCOOH to F(-) and CO(2) via C(3)F(7)COOH. With an initial S(2)O(8)(2-) concentration of 12.5mM and irradiation from a 200-W xenon-mercury lamp, C(3)F(7)CF=CHCOOH at a concentration of 680 microM was completely decomposed within 5 min. When 8.00 mM S(2)O(8)(2-) was used, the initial rate of C(3)F(7)CF=CHCOOH decomposition induced by 254-nm light irradiation was 45 times as high as that with photolysis alone. The apparent quantum yield for the C(3)F(7)CF=CHCOOH decomposition with 6.25 mM S(2)O(8)(2-) and 254-nm light was 2.4, indicating that virtually all SO(4)(-) anions produced by the photolysis of S(2)O(8)(2-) contribute to the decomposition of C(3)F(7)CF=CHCOOH.
authors.affiliation: National Institute of Advanced Industrial Science and Technology, AIST Tsukuba West, 16-1 Onogawa, Tsukuba 305-8569, Japan. h-hori@aist.go.jp
authors.forename: Hisao
authors.initials: H
authors.lastname: Hori
authors.forename: Ari
authors.initials: A
authors.lastname: Yamamoto
authors.forename: Kazuhide
authors.initials: K
authors.lastname: Koike
authors.forename: Shuzo
authors.initials: S
authors.lastname: Kutsuna
authors.forename: Issey
authors.initials: I
authors.lastname: Osaka
authors.forename: Ryuichi
authors.initials: R
authors.lastname: Arakawa
mesh_terms: D002264:Carboxylic Acids / Q000737:chemistry*; D005466:Fluorocarbons / Q000737:chemistry*; D010777:Photochemistry / Q000379:methods*; D017680:Potassium Compounds / Q000737:chemistry*; D013431:Sulfates / Q000737:chemistry*; D014867:Water / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry
chemical_list: D002264:Carboxylic Acids; D005466:Fluorocarbons; D017680:Potassium Compounds; D013431:Sulfates; D014874:Water Pollutants, Chemical; D014867:Water; C009007:potassium persulfate