Influence of support on catalytic activity of Ni catalysts in p-nitrophenol hydrogenation to p-aminophenol

The catalytic activities of kieselguhr-, TiO2-, and Al2O3-supported Ni catalysts in hydrogenation of p-nitrophenol to p-aminophenol were investigated. The supported Ni catalysts were characterized by N-2 adsorption/desorption, X-ray diffraction, temperature-programmed reduction, and temperature-programmed desorption of ammonia techniques, The catalytic activities of the supported Ni catalysts were in an order of Ni/kieselguhr >> Ni/TiO2 > Ni/Al2O3. The acidities of the supported Ni catalysts were in an order of Ni/Al2O3 >> Ni/TiO2 > Ni/kieselguhr. The acidity of the supported Ni catalyst significantly affected the catalytic activity. (C) 2008 Elsevier B.V. All rights reserved.