摘要
Application of high resolution^(13)C nuclear magnetic resonance(NMR)spectroscopy to characterize crude oil was demonstrated.The chemical shifts of^(13)C NMR functional groups that determine the composition of the oil sample were determined.Molar fractions of primary,secondary,quaternary,tertiary,aromatic groups,aromatic factor and average hydrocarbon chain length of aliphatic hydrocarbons of the oil sample according to^(13)C NMR spectra were determined.Detailed description of the^(13)C NMR spectra of the oil sample using a single consideration of three NMR spectra:^(13)C,^(13)C Attached Proton Test(APT),^(13)C with Gated Decoupling(GD)was performed.The different contribution of the studied oil sample in the aliphatic(10e75 ppm)and aromatic(115e165 ppm)areas of the^(13)C NMR spectra was determined.The presence of all major hydrocarbon components in the studied oil sample was established on the quantitative level,the aromaticity factor and the mean length of the hydrocarbon chain were evaluated.Quantitative fractions of aromatic molecules and functional groups constituting oil hydrocarbons were determined.In this work we demonstrate that the attached proton test and gated decoupling^(13)C NMR spectroscopy can afford all information to complete the chemical shift assignment of an oil sample,especially for determination of long range 1He^(13)C coupling constants and^(13)C multiplicity.
基金
the Ministry of Science and Higher Education of the Russian Federation under agreement No.075-15-2020-931 within the framework of the development program for a world-class Research Center"Efficient development of the global liquid hydrocarbon reserves.".
