Study on the Composition of Asphaltenes in Oils of Various Chemical Nature Using Oxidation Catalysed by Ruthenium Ions

The structure of asphaltenes of oils sampled in various oil and gas provinces and differing from each other in chemical types and contents of asphaltene components has been studied using an oxidation reaction catalysed by ruthenium ions. Structural fragments, covalently bound through Car-C links with the aromatic rings of their molecules, and the compounds occluded in the hollow cells of macromolecular structures in asphaltenes are shown to be present in all the samples under investigation. The covalently bound fragments are represented by normal and branched alkanes, cheilanthanes, gopanes, and aromatic structures of the biphenyl type. Typical biological markers, n-alkanes and hopanes, have been identified among occluded compounds. n-Alkylbenzenes, n-alkyltoluenes, n-alkylxylenes, n-alkyltrimethylbenzenes, and alkylbenzothiophenes are additionally found in the composition of non-oxidised naphthenic aromatic oil compounds.