The catalytic performance of cobalt catalysts supported on gamma-Al2O3, TiO2, ZrO2 were studied for bio-ethanol steam reforming (BESR) reaction. The supported catalysts (10 wt%Co) were prepared by impregnation and characterized through Thermogravimetric analysis (TGA), H-2 chemisorption, laser Raman Spectroscopy, Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFrS), and temperature-programmed reaction (TPRxn). The metallic cobalt sites were found to correlate with the BESR reaction activity. The reaction and H2 chemisorption showed that ZrO2 supported catalyst showed the best dispersion and best catalytic activity. Over the 10% Co/ZrO2 catalyst, using a H2O:EtOH:inert molar ratio of 10:1:75 and a GHSV = 5000 h(-1), 100% ethanol conversion and a yield of 5.5 mol H-2/Mol EtOH were obtained at 550 degrees C and atmospheric pressure. (c) 2007 Elsevier B.V. All rights reserved.