The pyrolysis products of twelve Ca to C9 alkanes have been analyzed by gas chromatography. The compositions of the products are tentatively predicted on the basis of a classical radical mechanism, taking into account radical isomerizations by 1-4 and 1-5 intramolecular transfers of hydrogen atoms. In the experimental conditions used in this work (temperature, 440-500'; pressure, 3 to 20 bars; reactor of clean sealed Pyrex tubes) the reaction is homogeneous, and hydrogen is formed only in small amounts. The experimental results are shown to be in agreement with theory if it is assumed that 1-5 hydrogen atom transfers are very fast and that the rates of 1-4 and intermolecular transfers are often similar, their relative value depending much on steric hindrance.

The rate of formation of alkanes in the pyrolysis of n-hexadecane is shown to be drastically reduced in the presence of an inert gas.The experimental results are in good quantitative agreement with the predictions of a theoretical model, which assumes that the decomposition of alkyl radicals is not monomolecular, because the Maxwell–Boltzmann activation process would be perturbed by a bimolecular reaction having a lower activation energy.