Preparation and Performance of Ni<sub>2</sub>P/TiO<sub>2</sub>-Al<sub>2</sub>O<sub>3</sub> for Hydrodenitrogenation

A series of TiO2-Al2O3 composite supports were prepared by hydrolysis and deposition of tetrabutyl titanate on macropore Al2O3, and the nickel phosphide catalyst, Ni2P/TiO2-Al2O3, Ni2P/TiO2 and Ni2P/ Al2O3 were prepared by incipient wetness impregnation and in situ H2 reduction method. Their hydrodenitrogenation(HDN) performance were evaluated on a continuous-flow fixed-bed reactor by using quinoline as the model molecules . The results show that the TiO2-Al2O3 composite support still retained the pore properties of macropore Al2O3, and anatase TiO2 were well dispersed on the Al2O3 surface. Different supports had great influence on the reduction behaviour of the oxidic precusors and HDN activity of phosphide catalysts.The main active phase after reduction was Ni2P phase for the TiO2 supportd catalyst, but only Ni12P5 appeared for the TiO2-Al2O3 and Al2O3 supported catalyst. The TiO2-Al2O3 supported catalyst with the Ti /Al atomic ratio of 0.12 exhibited the highest HDN activity among all catalysts.