KINETICS OF VAPOR-PHASE HYDROCARBON–OZONE REACTIONS

Abstract

The reactions of nine olefinic and aromatic hydrocarbons with ozone in the vapor phase have been investigated in static and dynamic systems. Some of the rate constants for the olefin–ozone reactions are in good agreement with previously published data, whereas others are larger than values previously reported. Rate constants for trans-2-butene–, isobutene–, and ethylene–ozone reactions were measured between 30 and 100 °C. The activation energies for the reaction of ozone with trans-2-butene, isobutene, and ethylene are 0.2 ± 0.3, 2.8 ± 0.4, and 4.2 ± 0.4 kcal/mole. In general, the reactions of hydrocarbons with ozone are non-stoichiometric. However, these reactions do appear to be second order. The rates of reaction between alkylbenzenes and ozone are too low to be of importance in air pollution studies.