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The electric power generation, and hydrogen as a vector, in fuel cells, is a process of high energy efficiency and low environmental impact. However, hydrogen production has its still high cost, because the H2 gas is not available in nature. Therefore, we study the steam reforming reaction of ethanol for the production of H2, featuring an environmentally friendly process, with low CO2 emissions in nature as well as being economically viable in Brazil, a major world producer of ethanol. Assuming the reform of ethanol follows similar mechanism to the methanol reforming, whose catalyst for industrial use is composed of Cu/ZnO/Al2O3, it can be considered that copper catalysts on n-type semiconductor oxide should be effective in reforming reaction ethanol. Thus, replacement of zinc oxide of niobium pentoxide, both characteristics semicondução n-type catalysts may generate similarly. In this work study the performance of the catalysts Cu/ZnO/Al2O3 (commercial catalyst HiFUEL Alfa Aesar) and Cu/Nb2O5/Al2O3 in the ethanol steam reforming reaction. The catalysts were characterized by adsorption/desorption of N2 and NH3-TPD analysis. The catalytic tests were carried out using a mixture of water:ethanol in a molar ratio equal to 10:1, reactant liquid flow rate of 1 ml/min to 573K. The gaseous product was analyzed on-line by gas chromatography. Results of the textural analysis show that the synthesized catalyst has a specific surface area about three times greater than the commercial catalyst, which has micropores on its surface. For NH3-TPD analysis it showed that the strongest acid sites are the commercial catalyst than in the synthesized catalysts. This may occur due to the provision of materials on the catalyst surface, a consequence of the preparation method of the catalyst and the use of different materials. The catalysts showed similar behavior as the selectivity for hydrogen, but the synthesized catalyst showed higher conversion than the commercial catalyst. In analyzing the gaseous products, there was significant production of H2 and CH4 in the reaction with both, and small amounts of CO2, C2H4 and C2H6 but only the synthesized catalyst was carbon monoxide. The catalytic tests show that the conversion and the production of hydrogen by the reaction between water and ethanol is more satisfactory the weaker the acidity of the catalyst, disfavoring the ethanol dehydration reaction.