Sequence studies in liquid phase hydrocarbon oxidation. Part 4.—Hydroperoxide-alcohol and hydroperoxide-ketone transitions in the oxidation of ethylbenzene

Abstract

The rates of consumption of α-phenylethylhydroperoxide molecules during the oxidation of ethylbenzene at 120°C have been measured using radioactive tracer procedures; balance equations for the total activities and concentrations were used for the calculations. In order to obtain a coherent set of rates a hydrogen transfer reaction between hydroperoxide molecules and peroxy radicals had to be taken into account. It was established that ketone and alcohol molecules were formed mainly as a result of the induced decomposition of the hydroperoxide and the contribution to their formation by termination processes was <10 % of their total formation rates. The formation rates of alcohol and ketone via hydroperoxide molecules were very similar. The relative reactivity of hydroperoxide and ethylbenzene molecules toward peroxy radicals was found to be two. Further kinetic data, such as ease of oxidation and kinetic chain length both for the oxidation of the parent hydrocarbon and its main intermediate, have been determined.