Rate constants for the reaction of OH radicals with CHF2Cl, CF2Cl2, CFCl3, and H2 over the temperature range 297–434 °K

Abstract

Rate constants for the reaction of OH radicals with CHF2Cl, CF2Cl2, CFCl3, and H2 have been determined over the temperature range 297–434 °K using a flash photolysis–resonance fluorescence technique. The following Arrhenius expressions were obtained: k1(CHF2Cl) =1.21×10−12e−(3250±300)/RT cm3 molecule−1 sec−1, k1(CF2Cl2) <1×10−15 cm3 molecule−1 sec−1 (T=297–424 °K), k1(CFCl3) <1×10−15 cm3 molecule−1 sec−1 (T=297–424 °K), k1(H2) =5.9×10−12 e−(3990±300)/RT cm3 molecule−1 sec−1. The rate constants for the reaction of OH radicals with H2, which were used to check the experimental system, are in good agreement with literature values. The atmospheric significance of the reaction of OH radicals with CHF2Cl is briefly discussed.