Abstract: A one-step method was employed to prepare nitrogen-doped carbon material/γ-Al₂O₃ composite materials, which was subsequently used as supports to fabricate NiW@NCAL hydrodesulfurization catalysts. All the catalysts were thoroughly characterized by using elemental analysis, XRD, N₂ adsorption-desorption, NH₃ - TPD, H₂ - TPR, UV-Vis DRS, XPS, TEM, and pyridine infrared spectroscopy. Compared with NiW@AL and NiW@CAL, the hydrodesulfurization activity of NiW@NCAL was evaluated, and their structure-activity relationship was investigated using dibenzothiophene as a model compound. The results indicate that the incorporation of carbon materials and nitrogen-doped carbon materials on the surface of γ-Al₂O₃ effectively weakens the strong interaction between the active metal phase and γ-Al₂O₃, thereby reducing the content of nickel-aluminum spinel and aluminotungstate. The catalytic activity is enhanced with the proportion of the highly active NiWS active phase, which is due to the higher sulfidation degree resulting from the surface incorporation.This not only effectively reduces the hydrogen consumption in hydrodesulfurization reactions but also produces high-value aromatic compounds as by-products.

Key words: nitrogen-doped carbon materials, γ-Al₂O₃, NiW catalyst, hydrodesulfurization, NiWS active phase