Comparison of oxide, sulfide, carbide and nitride Ni-W catalysts supported USY-Al2O3 for ring opening of decalin

Abstract

The bimetallic Ni-W oxide catalyst supported on USY- Al2O3 has been prepared and converted into Ni-W sulfide, carbide and nitride catalysts. These four types of catalysts have been characterized by surface area measurements, pulsed CO chemisorption, thermogravimetric analysis, X-ray diffraction, temperature-programmed reduction and pyridine infrared spectroscopy. The initial decalin reaction activity of the catalysts decreases in the order of carbide catalyst>oxide catalyst>sulfide catalyst>>nitride catalysts. The catalysts deactivation decreases in the order of: sulfide catalyst>carbide catalyst>>nitride catalyst>oxide catalyst. The initial ring-opening activity decreases in the order of carbide catalyst>oxide catalyst ∼sulfide catalyst>>nitride catalyst. The catalyst activity has relation with the metal sites, the amount of the strong Brönsted acid sites and the surface area on the catalyst. Besides these, the catalyst deactivation also has the close relation with the coke produced on the catalyst during the reaction.