Applied Catalysis A: General, Vol.413, 350-357, 2012
Nickel nanoparticles embedded in the framework of mesoporous TiO2: Efficient and highly stable catalysts for hydrodechlorination of chlorobenzene
Mesoporous TiO2-supported metallic Ni catalysts were prepared through a multicomponent assembly approach, where surfactant, titania, and nickel precursor were cooperatively assembled in a one-pot process. With the characterization of transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, N-2 physisorption, hydrogen temperature-programmed reduction, and hydrogen temperature-programmed desorption, the resultant Ni nanoparticles were identified to be homogenously embedded within the framework of TiO2 ranging in size from 1 to 6 nm. The embedment of Ni within the framework of support resulted in larger interface between Ni and support and thus stronger Ni-TiO2 interaction. During the gas-phase hydrodechlorination of chlorobenzene reaction, the as-prepared 0.23%-Ni/TiO2-DS delivered turnover frequency up to 1.5 times greater than that associated with the reference Ni/TiO2 catalyst prepared by conventional incipient-wetness impregnation method. Meanwhile, the as-prepared 0.23%-Ni/TiO2-DS also exhibited much improved stability for a continuous reaction of 30 h than the reference catalyst. The remarkable enhancement of the catalytic performances was found to depend on the strong metal-support interaction. (C) 2011 Elsevier B.V. All rights reserved.
Keywords:Nickel;Mesoporous titania;Embedment;Hydrodechlorination;Chlorobenzene;Metal-support interaction