Catalytic hydroconversion of Geting bituminous coal over FeNi–S/γ-Al2O3

• CHC over FeNi–S/γ-Al2O3 obviously increased the yield of soluble portion from GBC.
• Some –CH2− and –O − linkages could be connected to condensed aromatic rings in GBC.
• The catalytically formed active hydrogen atoms may play a crucial role in CHC of GBC.
• Polar and involatile species were identified by ASAP/TOF-MS analysis.

FeNi/γ-Al2O3 was prepared by thermally decomposing iron pentacarbonyl and nickel tetracarbonyl onto γ-Al2O3. Geting bituminous coal (GBC) was subjected to noncatalytic hydroconversion (NCHC) and catalytic hydroconversion (CHC) in the presence of FeNi/γ-Al2O3 and sulfur at 300 °C for 3 h. The reaction mixtures from both NCHC and CHC were fractionated to extracts 1–5 (E1–E5) by sequential extraction. The molecular compositions of E1–E5 were characterized with a Fourier transform infrared spectrometer, gas chromatography/mass spectrometer (GC/MS), and atmospheric solid analysis probe/time of flight-mass spectrometer (ASAP/TOF-MS). The results show that the yields of E1–E5 from CHC of GBC are obviously higher than those from NCHC. According to GC/MS analysis, the group components in E1 from the CHC are dominated by alkanes, arenes, and arenols in remarkable higher yields than those from NCHC, and most of the arenes and arenols are alkyl-substituted ones. The addition of active hydrogen atoms catalytically generated over FeNi–S/γ-Al2O3 to the ipso-position of condensed aromatic rings (CARs) in GBC could play a crucial role in cleaving–CH2− and–O − linkages connected to the CARs and thereby enhanced the yields of alkylarenes and alkylarenols through CHC. Meanwhile, the partial hydrogenation of some CARs during CHC could promote the radical hydrogen transfer along with thermal rupture of some relatively strong bonds to produce soluble molecules. According to ASAP/TOF-MS analysis, the soluble species from both NCHC and CHC have molecular mass distributions ranging from 100 to 500 u. A series of polar and/or involatile organic species.