The gas phase reactions of hydroxyl radicals with a series of aliphatic alcohols over the temperature range 240–440 K

Abstract Absolute rate constants were determined for the gas phase reactions of OH radicals with a series of aliphatic alcohols using the flash photolysis resonance fluorescence technique. Experiments were performed over the temperature range 240–440 K at total pressures (using Ar diluent gas) between 25–50 Torr. The kinetic data for methanol ( k 1 ), ethanol ( k 2 ), and 2‐propanol ( k 3 ) were used to derive the Arrhenius expressions\documentclass{article}\pagestyle{empty}\begin{document}$$ k_1 = (4.8 \pm 1.2) \times 10^{ - 12} \exp [- (480 \pm 70)/T]\,{\rm cm}^3\, {\rm molecule}^{ - 1} {\rm s}^{ - 1} $$\end{document}\documentclass{article}\pagestyle{empty}\begin{document}$$ k_2 = (7.4 \pm 3.2) \times 10^{ - 12} \exp [- (240 \pm 110)/T]{\rm cm}^3 {\rm molecule}^{ - 1} {\rm s}^{ - 1} $$\end{document}and\documentclass{article}\pagestyle{empty}\begin{document}$$ k_3 = (5.8 \pm 1.9) \times 10^{ - 12} \exp [- (30 \pm 90)/T]\,{\rm cm}^3\, {\rm molecule}^{ - 1} {\rm s}^{ - 1} $$\end{document}At 296 K, the measured rate constants (in units of 10 −13 cm 3 molecule −1 s −1 ) were: k 1 = (8.61 ± 0.47), k 2 = (33.3 ± 2.3), and k 3 = (58.1 ± 3.4). Room temperature rate constants for the OH reactions with several other aliphatic alcohols were also measured. These were (in the above units): 1‐propanol, (53.4 ± 2.9); 1‐butanol, (83.1 ± 6.3) and 1‐pentanol, (108 ± 11). The results are discussed in terms of the mechanisms for these reactions and are compared to previous literature data.