A new shock tube study of the H + O2 → OH + O reaction rate using tunable diode laser absorption of H2O near 2.5 μm

The rate coefficient of the reaction H + O2 → OH + O was determined using tunable diode laser absorption of H2O near 2.5 μm behind reflected shock waves over the temperature range 1100–1530 K, at approximately 2 atm. Detailed kinetic analysis of the recorded H2O temporal profiles yielded the rate coefficient expression: k = (1.12 ± 0.08) × 1014 exp [(−7805 ± 90)/T] cm3 mol−1 s−1, with estimated uncertainties of ±4.6% at 1500 K and ±8.8% at 1100 K. Excellent agreement between this study and that of Masten et al. (1990) was found in the overlapping temperature range. By combining the results of these two studies, the reaction rate coefficient over the range 1100–3370 K was found to be described well by: k=(1.04±0.03)×1014exp[(-7705±40)/T]cm3mol-1s-1.