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High volatile bituminous coal was demineralized by a chemical method.The vibrations of the "aromatics" structure of graphite,crystalline or non-crystalline,were observed in the spectra at the 1600 cm-1 region.The band at 1477 cm-1 is assigned as VR band,the band at 1392 cm-1 as VL band and the band at 1540 cm-1 as GR band.Graphite structure remains after chemical leaching liberates oxygenated functional groups and mineral groups.The silicate bands between 1010 and 1100 cm-1 are active in the infrared (IR) spectrum but inactive in the Raman spectrum.Absorption arising from C-H stretching in alkenes occurs in the region of 3000 to 2840 cm-1.Raman bands because of symmetric stretch of water molecules were also observed in the spectrum at 3250 cm-1 and 3450 cm-1.Scanning electron microscopy analysis revealed the presence of a graphite layer on the surface.Leaching of the sample with hydrofluoric acid decreases the mineral phase and increases the carbon content.The ash content is reduced by 84.5wt% with leaching from its initial value by mainly removing aluminum and silicate containing minerals.