Ethanol adsorption on platinum catalysts supported on Al2O3 and ZrO2 was studied by temperature-programmed desorption (TPD) and DRIFTS analysis. TPD of ethanol showed that the alumina support favoured the dehydration and decomposition ethanol, besides the water-gas shift reaction. DRIFTS analyses showed different intermediate species on the Pt/Al2O3 and Pt/ZrO2 catalysts. On the Pt/Al2O3 catalyst it was observed formation and decomposition of acetate species. On the Pt/ZrO2 were observed ethoxy species. Catalytic tests of the partial oxidation of ethanol showed that the H-2 selectivity was higher on the Pt/Al2O3 compared to the Pt/ZrO2 catalyst. Marked difference was observed for the H-2/CO ratio, suggesting preferential WGSR for Pt/Al2O3 and the reverse WGSR for the Pt/ZrO2 catalyst. These results allowed proposing different reaction routes.