Kinetics and products of the reactions of CH3O2 with Cl and ClO

The mechanisms of the reactions CH3O2 + Cl --> products (1) and CH3O2 + ClO --> products (2) have been studied at 298 K using a discharge now reactor coupled to laser induced fluorescence for the detection of CH3O, observed as a product of both reactions, and mass spectrometry for the detection of other species. In the kinetic study of reaction (1), the channel producing the Criegee radical, CH2O2, has been found to be preponderant compared to the CH3O forming channel : CH3O2 + Cl --> CH3O + ClO (1a), k(1a) = (2.0 +/- 0.4) x 10(-11) cm(3) molecule(-1) s(-1) and CH3O2 + Cl --> CH2O2 + HCl (1b), k(1b) = (2.0 +/- 0.4) x 10(-10) cm(3) molecule(-1) s(-1). The study of reaction (2) aimed at identifying the reaction pathways : CH3O2 + ClO --> CH3O + ClOO (2a) and CH3O2 + ClO --> CH3OCl + O-2 (2b). The branching ratio for the first channel has been determined : alpha(2a) = 0.3 + 0.1. These results are compared with other recent literature data and their atmospheric implication is briefly discussed.