Absolute Rate Constant for the Reaction of O(3P) with Ethanol

Article abstract of DOI:10.1021/j100402a049

The rate constant for the reaction of atomic oxygen with ethanol was measured directly by two experimental techniques: flash photolysis-resonance fluorescence (FP-RF, 297-886 K) and discharge flow-resonance fluorescence (DF-RF, 298-706 K).Kinetic complications in the DF-RF experiments from a fast secondary reaction and heterogeneous effects were overcome by operating at very low initial O-atom concentrations combined with the addition of excess O2.Under these conditions results obtained in the DF-RF experiments were in very close agreement with those from the FP-RF work, which was not perturbed by any apparent complication.The combined results show slight non-Arrhenius behavior and the data were accordingly fit to a three-parameter expression, 298-886 K, k₁(T) = 9.88 * 10^-19T^2.46 exp(-932/T), in units of cm³ molecule^-1 s^-1, with an error limit of about +/- 15percent over the given temperature range.In addition, initial variation experiments were carried out at 298 K in the DF-RF apparatus to investigate the mechanism of this reaction, and model calculations for an assumed mechanism were performed.Finally, the branching ratios for the three possible H-abstraction channels are discussed in light of the non-Arrhanius behavior displayed in the present rate data.