Preparation of supported nickel phosphide catalyst by surface modification method and its performance in hydrodeoxygenation

With MCM-41 as support, the supported Ni₂P/MCM-41 catalyst is prepared by first reducing the Ni₂P precursors at low temperature (673 K) and then modifying the surface with air; the as-prepared Ni₂P/MCM-41 catalyst was characterized by X-ray diffraction (XRD), N₂-sorption, scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS) and CO uptake. The catalytic performance of Ni₂P/MCM-41 in hydrodeoxygenation (HDO) of benzofuran (BF) was investigated to elucidate the effect of surface modification with air on the catalyst structure and HDO activity. The results show that pure Ni₂P acts as the active phase on the surface of modified Ni₂P/MCM-41 catalyst; the surface modification can decrease the aggregation of P species and promote the formation of small and highly dispersed Ni₂P active phase. Under 573 K, 3.0 MPa, a weight hourly space velocity of 4.0 h^-1 and a H₂/oil volume ratio of 500, the yield of O-free products reaches 88% for HDO of BF over the modified Ni₂P/MCM-41 catalyst, which is about 50% higher than that over the catalyst prepared by conventional temperature-programmed reduction method.