MCM-41 mesoporous molecular sieves supported nickel - physico-chemical properties and catalytic activity in hydrogenation of benzene

Siliceous, aluminosilicate and niobosilicate mesoporous molecular sieves of MCM-41 type have been used as matrices for nickel incorporated via the wet impregnation. The N-2 adsorption, XRD, H-2-TPR and Ni dispersion study were applied for the characterization of the prepared catalysts. The metal-support interaction (MSI) was the highest in Ni/NbMCM-41 material as indicated from H-2-TPR results, in which the highest dispersion of nickel occurs. Hydrogen chemisorption strength and the reducibility of Ni-species are inversely proportional to MSI strength. Both parameters determine the catalytic activity of the mesoporous materials in the hydrogenation of benzene at higher temperatures (423-473 K), whereas their activity at lower temperatures increases with increasing Ni dispersion. The kinetic study allows the determination of the activation energy in the benzene hydrogenation on Ni/MCM-41 which is very low, 36.5 kJ mol(-1). (C) 2002 Elsevier Science B.V. All rights reserved.