Research on properties and hydrotreating activity of alumina-supported nickle molybdenum nitrides

A series of alumina-supported nickel molybdenum nitrides were prepared by temperature programmed reduction successfully. Their physic-chemical properties were determined by XRD, BET, H₂-TPR and XPS, and their catalytic performance were evaluated through the hydrotreating reaction with thiophene or tetralin as feedstock. Based on the results of XRD, it can be concluded that the crystalline structure of supported nickel molybdenum nitrides was Ni₂Mo₃N. From H₂-TPR analysis, it was found that the peak at low temperature range (200℃~400℃) was due to the reduction of surface oxygen on passivated nickel molybdenum nitrides. XPS results showed that there were Mo⁶⁺, Mo⁴⁺ and Mo^δ+ ions on the surface of supported nickel molybdenum nitrides, among which the content of Mo^δ+ ions was the most. Nickel molybdenum nitrides catalysts had good HDS activity and stability. But their HDA stability was not satisfied, especially with the presence of sulfur.