Construction and modification of macromolecular structure model for vitrinite from Shendong 2^-2 coal

Sink-float centrifugation was used to get the vitrinite (SDV) from Shendong raw coal. The SDV was studied by ¹3C-CP/MAS NMR to reveal the structure characteristics of carbon atom and 12 structure parameters. The results indicate that naphthalene with condensation degrees of 2 is the main form of aromatic carbon in SDV. Benzene ring and aromatic ring with heteroatom is another existing form. Based on structure parameters and elemental analysis, macromolecular structure model of SDV is constructed. ¹3C chemical shift of SDV macromolecular structure is calculated by commercial software of ACD/CNMR predictor. According to the calculation results, macromolecular structure model of SDV is corrected, and finally the calculated chemical shift diagram of model can tally well with the experimental result.