SHOCK-TUBE STUDY OF THE REACTION BETWEEN CH3 AND H-2

The reaction between CH3 radicals and H-2 was investigated in shock wa ves at temperatures between 1250 and 1950 K and densities from 3 to 20 mol/m(3) using C2H6N2 and CH3I as methyl radical sources. CH3 consump tion was followed using time resolved UV absorption at 213.9 nm. The r ate coefficient expressions k(1) = 2.1 x 10(13) exp(-7780K/T) cm(3) mo l(-1) s(-1) for the reaction of CH3 with H-2 and k(13) = 3.2 x 10(13) exp(-13400K/T) cm(3) mol(-1) s(-1) for the CH3I decomposition reaction in Ar were derived. By use of the equilibrium constant and measured k (1) values, the expression k(-1) = 4.4 x 10(14)exp(-7840K/T) cm(3) mol (-1) s(-1) for the reaction CH4 + H --> CH3 + H-2 was derived.