Coal of Vorkuta region: composition of hydrocarbons of biomarkers, possibility of obtaining an ashless concentrate

The biomarkers composition of bitumen isolated from the Vorkuta region coals (the Vorgashorskaya, Komsomolskaya and Oktyabrskaya mines) was studied by gas-chromatography-mass spectrometry. The values of Paq and Pwax coefficients indicate a pronounced contribution of aquatic vegetation to the composition of the initial organic mass of the coals, while the distribution of C27-C29 sterane hydrocarbons is characterized by the dominance of C29 sterane. The coals of the Vorkuta region were heterogeneous in composition of the aromatic fraction of bitumen. The predominance of the retene is characteristic for the coals of Vorgashor, as for coal of Komsomolskaya and Oktyabrskaya, this hydrocarbon does not stand out against the background of other aromatic compounds. For the three coal samples ashless extracts were obtained with N-methylpyrrolidone. The resulting hypercoal was studied by solid state13C NMR. Significant differences in the chemical structure of the initial coal, hypercoal and residue are not recorded.