Preparation of Ni-Mo2C/carbon catalysts and their stability in the HDS of dibenzothiophene

•Carbothermal hydrogen reduction (CHR) temperature decreased to 550 °C by Ni addition in Ni-Mo2C/carbon catalyst synthesis.•Ni addition increases S uptake during HDS, resulting in the rapid formation of Mo2C-MoS2 core-shell structures.•The core-shell Mo2C-MoS2 structures promote direct desulfurization (DDS) of dibenzothiophene.•HDS activity of Mo2C enhanced with Ni addition up to Ni:Mo < 0.38.

The HDS activity and stability of Ni-Mo2C/AC catalysts, prepared by carbothermal hydrogen reduction (CHR) at different temperatures and with different Ni:Mo ratios, is reported. The highest HDS activity occurred for catalysts with Ni:Mo ratios of 0.38 and 0.19, when prepared at the relatively low CHR temperature of 550 and 600 °C, respectively. Partial sulfidation of the Ni-Mo2C/AC catalysts occurred rapidly upon reaction in 2 wt% dibenzothiophene (DBT) at 350 °C and 2.1 MPa H2. Uptake of S was enhanced with increased Ni content, resulting in the formation of Mo2C-MoS2 core-shell structures. The stack height of the MoS2 shell increased with increased Ni content and promoted the direct desulfurization of DBT.

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