Slurry-Phase Hydrogenation of Different Asphaltenes to Liquid Fuels on Dispersed MoS2 Nanocatalysts

Xiaoping Wang; Huaijun Ma; Donge Wang; Lin Wang; Yiwen Yang; Jianqiang Han; Wei Qu; Lin Yang; Shuaiqi Wang; Zhijian Tian

doi:10.1021/acsomega.3c01174

Slurry-Phase Hydrogenation of Different Asphaltenes to Liquid Fuels on Dispersed MoS₂ Nanocatalysts

ACS Omega. 2023 Apr 26;8(18):16384-16394. doi: 10.1021/acsomega.3c01174. eCollection 2023 May 9.

Authors

Xiaoping Wang^{1

2}, Huaijun Ma¹, Donge Wang¹, Lin Wang¹, Yiwen Yang¹, Jianqiang Han¹, Wei Qu¹, Lin Yang^{1

2}, Shuaiqi Wang^{1

2}, Zhijian Tian¹

Affiliations

¹ State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P.R. China.
² University of Chinese Academy of Sciences, Beijing 100049, P.R. China.

Abstract

Asphaltene, the most complex and recalcitrant fraction of heavy oil, was investigated in this study to gain new insights into its structure and reactivity. Two types of asphaltenes, ECT-As and COB-As, were extracted from ethylene cracking tar (ECT) and Canada's oil sands bitumen (COB), respectively, and used as reactants for slurry-phase hydrogenation. Characterization of ECT-As and COB-As was carried out by a combination of techniques, including XRD, elemental analysis, simulated distillation, SEM, TEM, NMR, and FT-IR, to gain insights into their composition and structure. A dispersed MoS₂ nanocatalyst was used to study the reactivity of ECT-As and COB-As under hydrogenation conditions. The results showed that under optimal catalytic conditions, the vacuum residue content of hydrogenation products could be reduced to less than 20%, and the products contained over 50% light components (gasoline and diesel oil), indicating that ECT-As and COB-As were effectively upgraded. The characterization results indicated that ECT-As contained a higher aromatic carbon content, shorter alkyl side chains, fewer heteroatoms, and less highly condensed aromatics than COB-As. The light components (gasoline and diesel oil) of ECT-As hydrogenation products mainly consisted of aromatic compounds with 1-4 rings, with the alkyl chains mainly composed of C1-C2, while light components of COB-As hydrogenation products were mainly composed of aromatic compounds with 1-2 rings and C11-C22 paraffins. The characterization of ECT-As and COB-As and their hydrogenation products revealed that ECT-As was an "archipelago type" asphaltene, composed of multiple small aromatic nuclei interconnected through short alkyl chains, while COB-As was an "island type" asphaltene, with long alkyl chains connected to aromatic nuclei. It is suggested that the structure of asphaltene has a significant impact on both its reactivity and product distribution.