title: Atmospheric chemistry of perfluorinated aldehyde hydrates (n-C(x)F(2x+1)CH(OH)2, x = 1, 3, 4): hydration, dehydration, and kinetics and mechanism of Cl atom and OH radical initiated oxidation.
abstract: Smog chamber/Fourier transform infrared (FTIR) techniques were used to measure k(Cl+C(x)F(2x+1)CH(OH)(2)) (x = 1, 3, 4) = (5.84 +/- 0.92) x 10(-13) and k(OH+C(x)F(2x+1)CH(OH)(2)) = (1.22 +/- 0.26) x 10(-13) cm(3) molecule(-1) s(-1) in 700 Torr of N(2) or air at 296 +/- 2 K. The Cl initiated oxidation of CF(3)CH(OH)(2) in 700 Torr of air gave CF(3)COOH in a molar yield of 101 +/- 6%. IR spectra of C(x)F(2x+1)CH(OH)(2) (x = 1, 3, 4) were recorded and are presented. An upper limit of k(CF(3)CHO+H(2)O) < 2 x 10(-23) cm(3) molecule(-1) s(-1) was established for the gas-phase hydration of CF(3)CHO. Bubbling CF(3)CHO/air mixtures through liquid water led to >80% conversion of CF(3)CHO into the hydrate within the approximately 2 s taken for passage through the bubbler. These results suggest that OH radical initiated oxidation of C(x)F(2x+1)CH(OH)(2) hydrates could be a significant source of perfluorinated carboxylic acids in the environment.
authors.affiliation: Department of Chemistry, University of Copenhagen, Universitet sparken 5, DK-2100 Copenhagen, Denmark.
authors.forename: M P
authors.initials: MP
authors.lastname: Sulbaek Andersen
authors.forename: A
authors.initials: A
authors.lastname: Toft
authors.forename: O J
authors.initials: OJ
authors.lastname: Nielsen
authors.forename: M D
authors.initials: MD
authors.lastname: Hurley
authors.forename: T J
authors.initials: TJ
authors.lastname: Wallington
authors.forename: H
authors.initials: H
authors.lastname: Chishima
authors.forename: K
authors.initials: K
authors.lastname: Tonokura
authors.forename: S A
authors.initials: SA
authors.lastname: Mabury
authors.forename: J W
authors.initials: JW
authors.lastname: Martin
authors.forename: D A
authors.initials: DA
authors.lastname: Ellis