Seven Hungarian coal samples of different ranks were examined by solvent extraction, liquid chromatographic (LC) separation of the extracts and analysis of the aliphatic and aromatic hydrocarbon LC fractions by high-resolution gas chromatography. The LC fraction distribution is characteristic of the coal. The gas chromatograms of the two hydrocarbon LC fractions show strong similarities for related samples and can server as "fingerprints" of the coals. For the n-alkanes, parameters such as "carbon preference index" can be calculated. For other aliphatic and aromatic hydrocarbons, respectively, the retention and "PAH indices" are presented. © 1981.
Alexander, G., & Hazai, I. (1981). Chromatographic Fingerprinting of coal extracts. Journal of Chromatography A, 217(C), 19–38. https://doi.org/10.1016/S0021-9673(00)88059-0