High resolution solid state 13C - NMR study of Feng Feng fat coal

Three samples of Feng Feng fat coal were investigated by 13C - CP, 13C - CP/ MAS TOSS and DD techniques. Twelve Structural parameters and the aromatic cluster size of each sample were obtained. From the study of the three samples, deashed coal, pyridine extraction residues and hydrogenated pyridine - insoluble products, it can be seen that both aromaticity (fa) and aromatic bridgehead (fB a) increased as the carbon content increased; While the aliphatic carbon decreased with increasing carbon content. The average carbon numbers of aromatic cluster in the three samples were 18, 18 and 19, respectively.