关键词: 磷化二镍, 加氢脱硫, 柠檬酸, 络合剂, 催化剂, 制备

Abstract: The TiO₂-Al₂O₃ complex support was prepared by the sol-gel method. A nickel phosphide catalyst, Ni₂P/TiO₂-Al₂O₃ with citric acid (CA) as chelating agent, was prepared by impregnation method using citric acid (CA) as complexing agent. The catalysts were characterized by X-ray diffraction (XRD) and N₂-adsorption specific surface area measurements (BET). The catalytic performance of Ni₂P/TiO₂-Al₂O₃ was investigated by hydrodesulfurization (HDS) of dibenzothiophene (DBT). The effects of different, immersion sequences, Ni/P molar ratios and Ni₂P loadings on catalytic activity were studied. The results showed that, when the Ni/P molar ratio was less than 1:1, the single Ni₂P phase can be obtained. However, Ni₃P phase can be observed with the Ni/P molar ratio of 2:1. The Ni₂P/TiO₂-Al₂O₃ prepared by co-impregnation method with Ni/P molar ratio of 1:1, a loading of 30% exhibits the optimized catalytic performance. When reaction temperature was 360℃, pressure was 3.0MPa, and hydrogen/oil ratio was 500, and liquid hourly space velocity was 2.0h^-1, the conversion of dibenzothiophene HDS was 99.5%.

Key words: nickel phosphide, hydrodesulfurization, citric acid, chelating agent, catalyst, preparation