Enrichment of oxygen-containing aromatics in an extract from Zhundong subbituminous coal

Zhundong subbituminous coal (ZSBC) was exhaustively extracted with isometric carbon disulfide (CDS)/acetone mixed solvent to afford extract 1 (E-1), which was sequentially extracted with petroleum ether (PE) and CDS to afford extracts 2 (E-2) and 3 (E-3). E-3 was gradiently eluted into effluent portions 1 to 5 (EPs 1 to 5) through a silica gel-packed column sequentially with PE, CDS/PE mixed solvents with volume ratio of 3:7, 1:1 and 7:3, and CDS. According to analysis with a gas chromatography/mass spectrometer, in total, 22 alkyl phenyl carbonates were enriched into EP3, and anthraquinone and its two derivatives, nine polycyclic aromatic ketones and two polycyclic aromatic lactones into EP4. Most of the oxygen-containing aromatics are value-added chemicals.