Preparation of Co-Mo/γ-Al2O3 catalyst and the catalytic hydrogenation effects on coal-related model compounds

Co-Mo/gamma-Al2O3 bimetallic catalyst was prepared by incipient wetness impregnation and the physicochemical properties were obtained by a series of characterization methods. The active components are mainly MoS2 and Co-Mo-S existing on gamma-Al2O3, the support. Meanwhile, the activity of catalyst in hydroconversion of four coal-related model compounds (CRMCs), dibenzyl ether, furan, thiophene and quinoline, was investigated. Hydroconversion products were analyzed by gas chromatography/mass spectrometry (GC/MS) and the possible reaction pathways were proposed according to the GC/MS data. Oxygen was removed from dibenzyl ether via the direct cleavage of Calk-O bridge bond to produce benzylium cation followed by the combination with H- to generate toluene. The hydroconversion of furan can be realized by the direct cleavage of C-ar-O bond and direct hydrogenation, respectively. For thiophene, H+ directly transferred to sulfur atom, leading to the cleavage of C-ar-S bond to produce H2S and 1,3-butadiene, which abstracted active hydrogen to yield butane. Another indirect desulfurization pathway for thiophene is hydrogenating to form tetrahydrothiophene and C-S bond cracking to produce butane. Hydroconversion of quinoline started with either N-ring or benzene ring, and the first one was the main pathway. (c) 2021 Energy Institute. Published by Elsevier Ltd. All rights reserved.