Experimental determination of the equilibrium constant of the reaction CH₃ + O₂ ⇄ CH₃O₂ during the gas‐phase oxidation of methane

Abstract

Abstract For the experimental determination of the equilibrium constant of the reaction CH 3 + O 2 ⇄ CH 3 O 2 (1), the process of methane oxidation has been studied over the temperature range of 706–786 K. The concentration of CH 3 O 2 has been measured by the radical freezing method, and that of CH 3 from the rate of accumulation of ethane, assuming that C 2 H 6 is produced by the reaction CH 3 + CH 3 → C 2 H 6 (2). The equilibrium constant of reaction (1) has been obtained at four temperatures. For the heat of the reaction the value Δ ˚H 298 = ‐32.2 ± 1.5 kcal/mol is recommended.