Long chain n-alkyl and n-alkylthio radicals : Reactivities towards hydrogen donor additives under gas phase condition

Abstract

Fossil fuel model compounds such as didodecylsulphide 1 , 1-dodecanethiol 2 and didodecylsulphone 3 were thermally decomposed under gas phase and short contact time reaction conditions with defined medium composition. Intermolecular H-transfer occurs with sulphided species while intramolecular β-scissions and H-transfers are probably involved during decomposition of the dodecyl radical. The appearance of light alkyl radicals and the presence of thiyl and mercapto radicals clearly activate thermal conversion of the starting material. H-donor additives have a weak effect on the various intramolecular mode of fragmentation of the n-alkyl chains but they are able to inhibit the activity of light and thiyl radicals improving the yield of liquid n-olefins. In all cases only traces of n-alkanes are formed by intermolecular H-transfer.