Rate constants for the reactions of CH3O with CH2O, CH3CHO and i-C4H10

The rate constants for the reactions of CH3O radicals with 3 reactants have been measured by two different techniques : laser photolysis (LP) and fast flow reactor (FF), both coupled with a detection of CH3O radicals by laser induced fluorescence. The reaction with formaldehyde CH2O has been measured in the temperature range 295 - 450 K. Both sets of results (LP and FF) are in excellent agreement and lead to a pressure independent rate constant of k(1) (1.1+/-0.3) x 10(-12) exp(-9.6+/-1.0 kJ mol(-1)/ RT) cm(3) s(-1). The reaction with acetaldehyde CH3CHO has been measured between 286 and 493 K. Both sets of experiments are again in excellent agreement and lead to a pressure independent rate constant of k(2) = (5.7+/-1.3) x 10(-13) exp(-5.2+/-0.7 kJ mol(-1)/RT) cm(3) s(-1). No reaction could be detected with isobutane i-C4H10 at temperature up to 356 K, leading to an upper limit for k(3) less than or equal to 2.5 x 10(-15) cm(3) s(-1).