Ni2P Catalysts Supported on Titania-Modified Alumina for the Hydrodesulfurization of Dibenzothiophene

• Published in: Industrial & engineering chemistry research 2011-10, Vol.50 (19), p.11043-11048
• Main Authors: Chen, Tao, Yang, Bolun, Li, Shasha, Wang, Kaile, Jiang, Xuedong, Zhang, Yong, He, Guanwei
• Format: Article
• Language: English
• Subjects: Applied sciences; Chemical engineering; Exact sciences and technology; Kinetics, Catalysis, and Reaction Engineering
• ISSN: 0888-5885; 1520-5045
• DOI: 10.1021/ie201188v

Nickel phosphide catalysts supported on the TiO2–Al2O3 composite oxide were successfully prepared by impregnation of nickel phosphate precursors followed by temperature-programmed reduction. The catalysts were characterized by X-ray diffraction, thermogravimetric analysis, IR spectroscopy, N2 adsorption, and X-ray photoelectron spectroscopy. The catalytic activity was characterized in a fixed-bed reactor for hydrodesulfurization using a model liquid-feed dibenzothiophene, which contained 2000 mg/kg sulfur. Experimental results indicate that the TiO2–Al2O3 composite support effectively prevents the formation of aluminum phosphates due to the strong interaction between phosphorus and γ-Al2O3, and it also shows strong interactions with Ni and P species on the surface, which is the main reason for the enhancement in hydrodesulfurization activity and stability. Among the Ni2P/TiO2–Al2O3 samples tested, the catalyst at a Ni loading of 15 wt % showed the highest activity with a steady-state dibenzothiophene conversion of 99.9% at 613 K, 2.5 MPa, WHSV 3 h–1, and volume ratio of hydrogen/oil of 450.