OH Reaction Kinetics and Atmospheric Impact of 1-Bromopropane

Abstract

The temperature-dependent rate constant for the reaction of the OH radical with 1-bromopropane has been measured using the discharge flow technique with laser-induced fluorescence detection of the OH radicals. Rate constants were measured as a function of temperature between T = 271 K and T = 363 K. The temperature dependence is well described by a simple Arrhenius expression, k(T) = A exp[−E/(RT)]. We find that A = (5.75 ± 0.9) × 10-12 cm3 molecule-1 s-1 and E/R = 504 ± 50 K for the OH reaction rate with CH3CH2CH2Br. The reaction rate at T = 277 K is 9.3 × 10-13 cm3 molecule-1 s-1, which implies that the atmospheric lifetime for CH3CH2CH2Br is approximately 15 days using the scaling method of Prather and Spivakovsky. In addition, the quantitative infrared spectrum for 1-bromopropane has been obtained using a Fourier transform spectrometer. Together with the atmospheric lifetime estimate, this spectrum implies global warming potentials of 1.0, 0.3, and 0.1 for integration time horizons of 20, 100, and 500...