Chemistry and structure of coal-derived asphaltenes, Phase I. Quarterly progress report, October--December 1975

Based on x-ray diffraction, a method has been developed for characterizing coals and coal-derived asphaltenes. The parameter thus obtained is termed aromaticity, an indicator for the amount of carbon atoms in the skeleton which is being aromatic. Provisional data indicate fairly large amounts of polar resin are still occluded in the crude asphaltene (separated by conventional pentane precipitation). This resin is more aromatic than the asphaltene from which the occluded resin has been removed. The extent of aromaticity has been estimated by both x-ray and color intensity methods.