Dynamic nuclear polarization 13C n.m.r. of coal

A novel n.m.r. method for determining the aromaticity of coal has been evaluated. Polarization transfer from the paramagnetic electrons is used to enhance the intensity of the 13C n.m.r. spectrum. Analysis of five samples of Gondwana bituminous steam coals shows that the aromaticity of inertinite is far greater than that of vitrinite and that variation of maceral composition is a major factor determining coal aromaticity. This has been confirmed by the study of maceral concentrates.