Abstract:The aim of the present work was to investigate steam reforming of ethanol with regard to H 2 production over transition metal catalysts supported on CeO 2 . Various parameters concerning the effect of temperature (400-800˝C), steam-to-carbon (S/C) feed ratio (0.5, 1.5, 3, 6), metal entity (Fe, Co, Ni, Cu) and metal loading (15-30 wt.%) on the catalytic performance, were thoroughly studied. The optimal performance was obtained for the 20 wt.% Co/CeO 2 catalyst, achieving a H 2 yield of up to 66% at 400˝C. In addition, the Co/CeO 2 catalyst demonstrated excellent stability performance in the whole examined temperature range of 400-800˝C. In contrast, a notable stability degradation, especially at low temperatures, was observed for Ni-, Cu-, and Fe-based catalysts, ascribed mainly to carbon deposition. An extensive characterization study, involving N 2 adsorption-desorption (BET), X-ray diffraction (XRD), Scanning Electron Microscopy (SEM/EDS), X-ray Photoelectron Spectroscopy (XPS), and Temperature Programmed Reduction (H 2 -TPR) was undertaken to gain insight into the structure-activity correlation. The excellent reforming performance of Co/CeO 2 catalysts could be attributed to their intrinsic reactivity towards ethanol reforming in combination to their high surface oxygen concentration, which hinders the deposition of carbonaceous species.