OXIDATION OF CH3CCL3 AND CH3CFCL2 IN THE ATMOSPHERE - KINETIC-STUDY OF OH REACTIONS

The kinetics of the reactions OH + CH3CCl3 (1) and OH + CH3CFCl2 (2) h ave been studied using the EPR discharge-flow method. Highly purified reagents were used in order to avoid any overestimation of the measure d rate constants due to the presence of reactive impurities. The resul ts are : k1 = (1.2 +/- 0.2) x 10(-14) at 298 K and k2 = (2.4 +/- 0.6) x 10(-12) exp [-(1790 +/- 100)/T] between 298 K and 479 K, in cm3 mole cule-1s-1. These data are compared with earlier ones, and their atmosp heric significance is discussed in relation with the calculation of th e tropospheric lifetimes or ozone depletion potentials of man-made hal ogenated molecules.