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

摘要： 采用溶胶-凝胶法制备了TiO₂-Al₂O₃复合载体, 以柠檬酸为络合剂, 浸渍法制备了负载型Ni₂P/TiO₂-Al₂O₃催化剂前体, 程序升温H₂还原法制备了Ni₂P/TiO₂-Al₂O₃催化剂, 并用 X 射线衍射(XRD)、N₂吸附比表面积(BET)测定技术对催化剂的结构和性质进行了表征, 考察了浸渍方法、Ni/P摩尔比、Ni₂P负载量对其进行的二苯并噻吩(DBT)加氢脱硫(HDS)性能的影响。结果表明, 当Ni/P比低于1:1时, 能得到单一的Ni₂P物相;当Ni/P比为2:1时, 开始出现Ni₃P物相。采用Ni/P比为1:1、Ni₂P负载量为30%、采用共浸渍方法制备的Ni₂P/TiO₂-Al₂O₃催化剂具有最好的活性, 在360℃、3.0MPa、氢油比500 (体积比)、液时体积空速2.0h^-1的条件下反应4h时, 二苯并噻吩转化率为99.5%。

关键词: 磷化二镍, 加氢脱硫, 柠檬酸, 络合剂, 催化剂, 制备