Effects of preparation method and sulfur poisoning on the hydrogenation and ring opening of tetralin on NiW/zirconium-doped mesoporous silica catalysts

Nickel-tungsten supported on zirconium-doped mesoporous silica catalysts was prepared by using different methodologies and successfully tested at the hydrogenation and ring opening of tetralin. The preparation method has an important influence on surface properties such as dispersion. location, and reducibility of NiW species as deduced from H-2-TPR, H-2 chemisorption, FTIR spectra of CO adsorbed, and XPS studies. Thus, when nickel, in the form of nickel citrate, is first incorporated followed by tungsten, a catalyst is obtained with the highest acidity and the best catalytic performance, yielding a full conversion of tetralin (100%) as well as high yields of hydrogenation (42.7%) and ring-opening (56.1%) products under mild conditions (6.0 MPa of H-2 and 375degreesC). This catalyst exhibits a good thiotolerance in the presence of 300 ppm of dibenzothiophene in the feed, maintaining a high catalytic activity in the hydrogenation and ring-opening reactions after 6 h on stream. (C) 2003 Elsevier Inc. All rights reserved.