Liquid-phase autoxidation of organic compounds at elevated temperatures. Absolute rate constant for intermolecular hydrogen abstraction in hexadecane autoxidation at 120–190°C

The absolute rate constants for the intermolecular hydrogen abstraction reactions of secondary hydrogens by secondary alkylperoxy radicals in hexadecane autoxidation, k₃, have been determined in the temperature range of 120–190°C using the stirred flow reactor technique. Absolute rate constants determined in this study for hexadecane are in good agreement with those determined for other hydrocarbons in liquid phase, on a per hydrogen basis, at lower temperatures. Arrhenius parameters for k₃/H derived from this study are A = 10^8.6 M^?1 s^?1 and E_a = 16.0 kcal/mol. The values of these parameters provide experimental confirmation for previous estimates made from both lower temperature reactions in the liquid phase and higher temperature reactions in the gas phase. © 1994 John Wiley & Sons, Inc.