Comparison of four different synthetic routes of Ni2P/TiO2-Al2O3 catalysts for hydrodesulfurization of dibenzothiophene

Ni2P/TiO2-Al2O3 is a very promising hydrodesulfurization catalyst, however the catalysts reported so far all use the temperature-programmed reduction (H-2-TPR) method and the reduction temperature can be as high as 973 K. It is important to develop more feasible methods to prepare this material. Herein, Ni2P/TiO2-Al2O3 catalysts were successfully synthesized at a low reduction temperature (573 K) based on NiCl2 center dot 6H(2)O and NH4H2PO2 (method I). Three other methods were also used to prepare the Ni-P/TiO2Al2O3 catalysts in this work. The catalysts were characterized using XRD, TEM, FT-IR, XPS, CO uptake, and N-2 sorption measurements. Experimental results indicate that the preparation method had a major influence on the physicochemical properties of the catalysts and the HDS activity. Among the four methods examined, method I could more effectively suppress the formation of AlPO4 and favor the formation of Ni2P, which can be attributed to the relatively low reduction temperature and the flowing hydrogen used in this method. The hydrodesulfurization activity results indicate that the Ni2P/TiO2Al2O3 catalyst prepared by method I gave a high HDS conversion of 100.0% at a reaction temperature of 583 K. The results suggest that method I provides a simple and energy-efficient route for the preparation of the Ni2P/TiO2-Al2O3 catalyst with excellent catalytic performance for the HDS of dibenzothiophene.