KMNAL OF zyxwvutsrq MO LEC ULA R C A TA LYSIS ELSEVIER Journal of Molecular Catalysis 88 ( 1994) 213-222 Effect of the method of preparing Ru-Mo/Si02 catalysts in their behaviour in CO hydrogenation M. Josefina Perez Zurita, Irene S. Henriquez, Mireya R. Goldwasser, M.Luisa Cubeiro Centro de Catdlisis, Petroleo y Petroquimica. Escuela de Quimica, Facultad de Ciencias. Universidad Central de Venezuela, Apartado Postal 47102, Caracas, Venezuela Geoffrey C. Bond* Department of Chemistry, Brunei University, Oxbridge, VB8 3PH, UK (Received June 10, 1993; accepted October 5, 1993) zyxwvutsrqponmlkjihgfedcbaZYXW Abstract Sequential impregnation of SiOZ by RuC13 and then by (N&) 6M07024, followed by drying and reduction in H, at 623 K, afforded catalysts in which, according to their benzene hydrogenation activity, the Ru particles were progressively covered by MO-containing species, the effect being greatest when RuCl, was introduced first. With catalysts of this type, in CO hydrogenation, oxygenate formation occurred at low MO content but was eliminated as the MO concentration was increased. When the MO salt was applied first to the support, oxygenate formation was greater and did not diminish significantly on raising the MO content. A semi-quantitative model is developed in which oxygenates are formed at Ru-MO sites; the hydrocarbon-forming process is not however much inhibited by the presence of MO, and may take place on MO species covering the Ru particles. Key words: carbon monoxide; hydrogenation; molybdenum; ruthenium: silica 1. Introduction Much effort has been devoted to the synthesis of higher alcohols from CO+H2. two strategies in particular having been explored: ( 1) the addition to methanol-forming metals, particularly Cu, of components to promote chain-growth, and (2) the modification of hydrocarbon-forming metals, particularly Ru, by adding components that suppress CO *Corresponding author. Fax. ( + 44-895) 256844. 0304-5102/94/$07.00 0 1994 Elsevier Science B.V. All rights reserved SSDI0304-5102(93)E0261-E