Mechanism of pyrolysis of some normal and branched C6-C9 alkanes. Composition of their pyrolysis products

Abstract

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.

Experimental study of hydrocarbon structure effects on the composition of its pyrolysis products

“…Studies of homological hydrocarbons were performed mainly for linear and non-linear alkanes [29,[35][36][37][38], but they were not aimed at developing the structure-selectivity relationships. Their goals were mainly the research of radical reactions mechanism including the confirmation of Rice-Kosiakoff theory [3,16,26,29,34,35,39], the estimation of reaction order and reaction rates of pyrolysis reactions [3,7,13,16,24,26,29,34,[39][40][41][42], or the effect of temperature on the selectivity of products formation [3,13,16,24,26,29,34,35,38,41].…”

Hydrocarbon fuel effects in solid-oxide fuel cell operation: an experimental and modeling study of n-hexane pyrolysis

“…12 Previous studies have shown that low conversion hexane pyrolysis proceeds via the Rice-Herzfeld mechanism and that the observed low conversion experimental behavior of n-alkanes can be accounted for with minor adjustments to the mechanism. [13][14][15] However, as already stated, under SOFC conditions fuel conversion might be extensive, and it is necessary to include secondary reactions to account for product distributions and the molecular weight growth that leads to observed deposit formation.…”

Coke Formation during Thermal Cracking of n-Octane

“…Models are suggested to explain the experimental data. Recently, Doue and Guiochon (1969) cracked octane at a relatively lower temperature of 443 "C and a pressure range of 2-10 bars with conversions varying from 1 to 4%. However, the gaseous products were only partially analyzed and no attempt was made to analyze the liquid products.…”