INTEGRATED, MULTIPLE-STAGE CHROMATOGRAPHIC METHOD FOR THE SEPARATION AND IDENTIFICATION OF POLYCYCLIC AROMATIC-HYDROCARBONS IN COMPLEX COAL LIQUIDS

A multiple-stage methodology is described for the separation and identification of neutral polycyclic aromatic hydrocarbons (PAH) in complex coal liquids. Fractional distillation followed by adsorption chromatography on neutral alumina with subsequent reverse-phase high-performance liquid chromatography were used for the isolation of neutral PAH subfractions. Capillary column gas chromatography, gas chromatography-mass spectrometry, and direct-probe mass spectrometry were used for the identification of sample components. This method results in chemically less complex subfractions which enable more detailed characterization of both trace level and major neutral PAH components.