Pd/h-BN materials have been synthesized in order to find an appropriate catalyst for the selective hydrogenation of lactose into lactitol. The catalysts were prepared by wet impregnation (WI) or aqueous impregnation (Al) and characterized by XRD, XPS, TEM and CO chemisorption. They were all tested in the hydrogenation of lactose in order to evaluate the potential of boron nitride as support in this reaction and also to understand the needs in terms of structural properties of the catalyst, in direct comparison with the oxidation of lactose. Pd/alpha-Al2O3 and Pd/gamma-Al2O3 were also prepared in order to evaluate the influence of the support. In all cases, the catalysts prepared by WI were more active and selective than those prepared by Al. In both reactions, the catalysts containing many Pd particles smaller than 3 nm were not active. The most active and selective catalyst towards lactitol by lactose hydrogenation presented, at the surface of the support, palladium particles of pyramidal shapes and no particles smaller than 3 nm. This particular shape seems to be well suited for the hydrogenation reaction because H-2 chemisorption can take place on the pyramid edges while lactose, requiring flat surfaces, could adsorb on the triangular pyramid faces. (C) 2014 Elsevier B.V. All rights reserved.