Bimetallic Ru/Ni supported catalysts for the gas phase hydrogenation of acetonitrile

摘要

A family of bimetallic Ni-Ru catalysts supported on a mesoporous SBA-15 silica was prepared by conventional impregnation method, with constant metal molar loadings, but varying Ni/(Ni + Ru) atomic ratios. The corresponding Ni and Ru monometallic catalysts were also prepared for comparison. These catalysts were characterized by XRD, N2 adsorption-desorption at -196 °C, TEM, XPS, H2-TPR, chemisorption of H2 at r.t., H2-TPD and NH3-TPD techniques. Finally, they were also tested in the hydrogenation of acetonitrile reaction, in the gas phase and at atmospheric pressure. Acetonitrile conversion values depended on the Ni/(Ni + Ru) composition of the bimetallic catalysts. Ru-rich bimetallic catalysts exhibited acetonitrile conversion values higher than that of pure Ni one; thus, although selectivity patterns remained almost unchanged, primary amine yields were increased. These higher conversion values resulted as a consequence of enhanced specific activity of Ni° atoms, attributable to a strong interaction between both metals, Ni and Ru, likely because NiRu alloy nanoparticles were formed.