Dependence of Coal Surface Wettability on the Petrographic Composition

Based on a comparison of elemental analysis data and IR- and C-13 NMR-spectroscopic data, principal differences in the chemical compositions of lithotypes isolated from Kuznetsk Basin coals of different ranks based on characteristic properties were established. The influence of the chemical composition and physical properties (porosity and surface topography) of the lithotypes on the wettability of their surfaces with water was found. It was shown that coals with high concentrations of fusainized components have increased surface hydration due to developed porosity, pronounced surface texture, coal matter mineralization, and the presence of aromatic fragments with substituted oxygen heteroatoms, which have greater hydrophilicity than that of hydrocarbon structures, in the organic matter of coal (OMC).