Relative rate coefficients of OH radical reactions with CF3CFCClCF3 and CF3CHCHCH2OH. Ozone depletion potential estimate for CF3CFCClCF3

Abstract

The relative rate method was used to determine the rate coefficients for the reactions of OH radicals with CF3CFCClCF3 (k1) and CF3CHCHCH2OH (k2). Experiments were carried out at (298 ± 2) K and atmospheric pressure using ultra pure air or ultra pure nitrogen as the gas bath. The k1 value was measured relative to those of chloroethane and ethane, and the k2 value was measured relative to those of cyclohexene and 1-pentene. The following rate coefficients were derived in units of cm3 molecule-1 s-1: k1 = (3.3 ± 0.9) × 10-13 and k2 = (3.3 ± 0.9) × 10-11. This is the first experimental determination of k1 and k2. The rate coefficients were used to estimate the atmospheric lifetimes for the studied haloalkenes considering the OH-initiated oxidation process. The ozone depletion potential (ODP) for CF3CFCClCF3 was estimated following a recently-developed technique based on Lagrangian trajectories, which takes into account the time and location of the release of the short-lived halogenated species. © 2012 Elsevier Ltd.