The compositional features of thermally soluble fractions from two Chinese coals in cyclohexane

Shengli lignite (SL) and Shenmu-Fugu subbituminous coal (SFSBC) were subjected to thermal dissolution in cyclohexane at 300°C for 1 h under hydrogen. The reaction mixtures were extracted with petroleum ether (PE) and the PE-extractable fractions (PEEFs) were analyzed with a gas chromatography/mass spectrometer. The results show that the PEEFs from thermally dissolved SL (TDSL) and thermally dissolved SFSBC (TDSFSBC) mainly consist of alkanes, alkenes, arenes, and oxygen-containing organic compounds (OCOCs); the yields of alkanes and alkenes in the PEEF from TDSFSBC are appreciably higher than those from TDSL, while the yields of arenes and oxygen-containing organic compounds in the petroleum ether-extractable fraction from thermally dissolved Shenmu-Fugu subbituminous coal are significantly lower than those from thermally dissolved Shengli lignite; arenols are dominant OCOCs in the PEEF from TDSL, while main OCOCs in the PEEFs from TDSFSBC are arenols and esters.