Atmospheric chemistry of C xF 2 x + 1 CH [dbnd]CH 2 ( x = 1, 2, 4, 6, and 8): Kinetics of gas-phase reactions with Cl atoms, OH radicals, and O 3

Abstract

Long-path length FT-IR-smog chamber techniques were used to study the title reactions in 700 Torr of N 2 or N 2/O 2, diluent at 296 K. There was no discernable effect of C x F 2 x + 1 -group size on the reactivity of C x F 2 x + 1 CH CH 2 towards Cl atoms and OH radicals. Values of k(Cl + C x F 2 x + 1 CH CH 2) = (9.07 ± 1.08) × 10 −11 cm 3 molecule −1 s −1 and k(OH + C x F 2 x + 1 CH CH 2) = (1.36 ± 0.25) × 10 −12 cm 3 molecule −1 s −1 were measured. Ozone reacts more rapidly with CF 3CH CH 2 than with larger members of the series; k(O 3 + CF 3CH CH 2) = (3.5 ± 0.3) × 10 −19 cm 3 molecule −1 s −1 and k(O 3 + C x F 2 x + 1 CH CH 2) = (2.0 ± 0.4) × 10 −19 cm 3 molecule −1 s −1 ( x ≥ 2). The atmospheric lifetime of C x F 2 x + 1 CH CH 2 ( x ≥ 2) is approximately 8 days with 90% of removal occurring via reaction with OH and 10% via reaction with O 3.