Buliangou subbituminous coal (BSBC) was sequentially extracted under ultrasonication with petroleum ether, carbon disulfide, methanol, acetone, and isometric carbon disulfide/acetone mixed solvent to afford extracts and residue (R-E) from the extraction. Then the R-E was subjected to sequential thermal dissolution (TD) at 320 degrees C with cyclohexane, benzene, methanol, ethanol, and isopropanol to afford soluble portions and residue (R-TD) from the TD. BSBC, R-E, and R-TD were characterized by Brunauer-Emmett-Teller method, X-ray photoelectron spectrometry (XPS), thermogravimetry, Fourier transform infrared (FTIR) spectrometry, and Curie-point pyrolysis (CPP)-gas chromatography/mass spectrometry to track the effects of the sequential extraction and TD on the coal structure. In total, 27.6 wt% of organic matter was released from BSBC by the ultrasonic extraction and subsequent TD. Both average pore diameter and total pore volume of R-E and R-TD increased; while specific surface area of R-E and R-TD decreased compared to the corresponding parameters of BSBC. No significant difference in the distribution of functional groups was observed in FTIR spectra between BSBC and R-E, while the absorbances of aliphatic and COO moieties significantly decreased in FTIR spectrum of R-TD compared to FTIR spectra of BSBC and R-E. According to the CPP-gas chromatography/mass spectrometric analysis, significant differences in the distributions among the volatile species from the pyrolyses of BSBC, R-E, and RID at 500 degrees C were observed. Alkenes and oxygen-containing species were only identified in the volatile species from the pyrolyses of BSBC and R-E rather than from the R-TD pyrolysis. The cleavage of C-alpha-C-beta bond in longer-chain alkylbenzenes and alkyltoluenes significantly proceeded during the pyrolysis. (C) 2016 Elsevier B.V. All rights reserved.