A series of TiO2 supported Ru-Cu bimetallic catalysts was investigated for the hydrogenolysis of glycerol. The catalysts were characterized by H-2 chemisorption, X-ray diffraction (XRD), scanning transmission electron microscopy (STEM/EDS) and X-ray photoelectron spectroscopy (XPS). The addition of copper led to an increase in the selectivity to 1,2-propanediol. The highest activity and selectivity was observed for a 1:1 Cu/Ru mass ratio. The results were explained in terms of the interaction between Ru and Cu. Copper diluted large Ru ensembles that are responsible for C-C bond cleavage leading to ethylene glycol production instead of the desired 1,2-propanediol. The presence of Cu also inhibited the deactivation exhibited by monometallic Ru. Among all the catalysts, the 2.5Ru-2.5Cu/TiO2 catalyst exhibited the best performance in the hydrogenolysis of glycerol. (C) 2014 Elsevier B.V. All rights reserved.