A Facile Method to Synthesize Ni2P Catalysts and their Catalytic Performances in Hydrotreating Reactions

The bulk and supported Ni2P catalysts (Ni2P/gamma-Al2O3 and Ni2P/MCM-41) were facile prepared by using nickel metal as nickel source via thermal treatment of hypophosphite in a separated reactor. The thermal decomposition behaviors of sodium hypophosphite were studied by online mass spectra. The effects of atmosphere, temperature, reaction time, and P/Ni atomic ratio on the as-prepared Ni2P catalysts were investigated. The Ni2P catalysts can also be obtained by using NiCl2 as nickel source but not for NiO. Since the nickel source is nickel metal and Ni2P catalysts were prepared in a separated reactor, the as-prepared Ni2P catalysts from Ni-0 can be directly used without further purification, but the as-synthesized Ni2P catalyst from NiCl2 source should be further treated to remove the residues (such as Cl-) before use. As the active species for hydrodenitrogenation (HDN), Ni2P shows much higher activity than Ni-0. For hydrodearomatization (HDA), Ni2P/MCM-41 shows much lower activity than Ni/MCM-41 but much better resistance to S-containing compounds in hydrogenation of naphthalene. The mechanism for synthesizing Ni2P catalysts with this facile method is proposed by online mass spectra.