Specifics of the composition of monocyclic aromatic hydrocarbons in asphaltite from the Ivanovskoe deposit

Research paper by V. R. Antipenko, O. A. Golubina, I. V. Goncharov, S. V. Nosova, S. B. Ostroukhov

Indexed on: 01 May '07Published on: 01 May '07Published in: Petroleum Chemistry


The molecular composition of alkyl substituted monocyclic aromatic hydrocarbons from asphaltite of the Ivanovskoe deposit was analyzed by means of the gas chromatography-mass spectrometry technique. Unlike most crude oils and natural bitumens, asphaltite is characterized by an unusual composition of practically all isobaric-homologous series of this class of hydrocarbons. The specific features of the composition of these series is a strong prevalence of C12-C23 1-alkyl-2,3,6-trimethylbenzenes with an irregular isoprenoid chain. These compounds are derivatives of isorenieratene, a carotenoid that occurs in anoxic photosynthetic green sulfur bacteria of the Chlorobiaceae family (Chlorobium genus). The ortho-isomers evidently prevail among C13-C25 alkyltoluenes, thus indicating a low level of catagenetic transformation of the asphaltite. n-Alkylbenzenes are practically absent from the monoalkylbenzene series; these are represented by the complete set of C17-C19 phenylalkanes. Such compounds were detected for the first time in natural bitumens.