For the purpose of extraction and identification of cyclic alkane hydrocarbons in oil from the Taribani field, Georgia, concentrates isolated from 200-350oC fractions have been studied. The concentrate preparation included the following steps: (a) distillation of a crude oil, (b) dearomatization of distillates by silica gel, (c) three-stage thermal diffusion separation of isoalkanes and cycloalkanes, and (d) thiourea adduction. Ten thermal diffusion fractions were obtained. A mixture of the IX and X fractions and separately the VIII fraction were studied. The extracts from these fractions with thiourea were studied as well. Composition of concentrates has been determined by the gas chromatography – mass spectrometry (GC-MS) method.The main components of the VIII thermodiffusion fraction were C11- C22 isoprenoid alkanes. Among them the predominant were pristane C19 and the phytane C20, the well-known biomarkers of oil. In the VIII thermodiffusion faction including dimethyl-, trimethyl-, tetramethyl-, ethyl-, methyl-ethyl-, diethyl-, propyl, methyl-propyl adamantanes, were identified.
 
 
 
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