Temperature-Dependent Kinetic Study of the Reaction of Hydroxyl Radicals with Hydroxyacetone.

The kinetics of the reaction of OH radicals with hydroxyacetone has been investigated as a function of temperature at a total pressure of helium of 2.0-2.1 Torr and over an extended temperature range of T = 250-830 K and as a function of pressure at T = 301 K in the pressure range 1.0-10.4 Torr. The rate constant of the reaction OH + CH3C(O)CH2OH → products (1) was measured using both absolute (from the kinetics of OH consumption in excess of hydroxyacetone) and relative rate methods (k1 = 4.7 × 10-22 × T3.25 exp (1410/T) cm3 molecule-1 s-1 at T = 250-830 K). The present data combined with selected previous temperature-dependent studies of reaction (1) yield k1 = 4.4 × 10-20 × T2.63 exp (1110/T) cm3 molecule-1 s-1, which is recommended from the present work at T = 230-830 K (with conservative uncertainty of 20% at all temperatures). k1 was found to be independent of the pressure in the range from 1.0 to 10.4 Torr of He at T = 301 K. The present results are compared with previous experimental and theoretical data.