Surface and structural properties of titania-supported Ru catalysts for hydrogenolysis of glycerol

A series of catalysts with different Ru contents supported on titania were prepared by conventional impregnation (IM) and deposition-precipitation (DP) methods. These catalysts were characterized by X-ray diffraction, temperature programmed reduction, transmission electron microscopy, X-ray photoelectron spectroscopy and CO chemisorption. The catalysts were evaluated for selective hydrogenolysis of glycerol. The glycerol conversion and the selectivity towards 1,2-propanediol depend on the method of catalyst preparation and on the Ru content. The catalyst with low Ru content exhibited maximum conversion, in turn was related to its dispersion. The catalysts prepared by DP method showed stable activity even with crude glycerol containing alkali salts as impurity. The catalyst exhibited consistent activity upon reuse. The high activity of Ru/TiO2 catalyst is due to the presence of well-dispersed nano size Ru particles on titania. The low activity of the IM catalyst is because of large domains of Ru and because of the presence of residual Cl- ions. (C) 2010 Elsevier B.V. All rights reserved.