NEGATIVE TEMPERATURE-COEFFICIENT IN THE C-2 TO C-13 HYDROCARBON OXIDATION .2. ANALYTICAL RESULTS

An analytical study is made of the products formed in the negative temperature coefficient zone for slow oxidation of alkanes. A clear increase in the formation of carbon oxides and olefins is obtained; these products are thought to be obtained from RCO3•, RCO•, and RO2• radicals. The results are explained by competition between two different mechanisms, namely L1 and L2. This competition explains the ratio of products obtained with various hydrocarbon oxygen ratios. The formation of olefins is shown to be assocated with the isomerization of RO2• radicals; the disproportionation reaction R• + O2 → olefin + HO2• is likely to be of a negligible importance, except in the case of t-C4H9 radicals. © 1979.