Computational modeling of the mechanisms of the free radical‐chain reaction of alkanes with oxygen. The oxidation of isobutane, n‐butane, and isopentane

Abstract A general computational method for obtaining complete solutions of time‐dependent kinetic equations has been developed and applied to free radical‐initiated reactions of alkanes with oxygen. The method has been applied to the low‐temperature, peroxide‐initiated oxidations of isobutane and isopentane. Using available independently measured and estimated values for the rate constants and activation parameters for each of the 20 proposed reaction steps for the oxidation of isobutane, the rates and products have been calculated for both the liquid phase and gas phase in the range of 100°–155°C. The calculated rates and products of oxidation agree with published experimental values. The oxidation of isopentane was examined by a 32‐reaction model. The rate constants were estimated using values for the appropriate rate steps in the oxidation of n‐butane and isobutane. The calculation of the oxidation rate and products agree with our experiments.