Effects of hydrogen and FeNi-S/γ-Al2O3 on the hydroconversion of extraction residue from Geting bituminous coal in cyclohexane

Extraction residue from Geting bituminous coal (ERGBC) via ultrasonic extraction with isometric carbon disulfide/acetone binary solvent was subjected to thermal dissolution (TD), thermal dissolution under pressurized nitrogen (TDN), non-catalytic hydroconversion (NCHC), and catalytic hydroconversion (CHC) in cyclohexane at 300 degrees C for 3 h. The catalyst was prepared by thermally decomposing Fe(CO)(5) and Ni(CO)(4) onto gamma-Al2O3. The reaction mixtures from TD, TDN, NCHC, and CHC were sequentially extracted with petroleum ether, carbon disulfide, methanol, acetone, and isometric acetone/carbon disulfide binary solvent to afford extracts 1-5 (E-1-E-5). Detailed characterizations of the extracts were performed with a gas chromatography/mass spectrometer (GC/MS) and Fourier transform infrared spectrometer. The results show that the yields of E-1 and E-3 from CHC are appreciably higher than those from others, suggesting the great influence of CHC on the breakage of -CH2- and -O-linkages connected to condensed aromatic rings. According to analysis with GC/MS, alkanes and arenes are the most abundant species in each E-1, in which most of the arenes are methylarenes. Arenols and phthalates are the predominant oxygen-containing organic compounds. Arenes with 1 or 2 ring(s) markedly increase by using H-2, especially in the presence of the catalyst. The H catalytically generated over FeNi-S/gamma-Al2O3 and the stabilizing effect of H-2 on the generated radicals could play crucial roles in cleaving bridged linkages connected to condensed aromatic rings and thereby enhance the yields of alkylarenes through NCHC and CHC. Related mechanisms for the formation of some species derived from NCHC and CHC of ERGBC are discussed. (C) 2016 Elsevier B.V. All rights reserved.