Resumen
Cu/Nb2O5 and Cu/Nb2O5/Al2O3 were studied as catalysts in ethanol steam-reforming for hydrogen production. They were prepared through impregnation, with different copper and Nb2O5 concentrations. Cu/ZnO/Al2O3 (G66), a commercial catalyst for methanol reforming was used for comparison. Temperature-programmed reduction data showed incomplete reduction of the copper, resulting in two reduction peaks, in opposition to CuO bulk, whose reduction occurred in one step (only one peak), it evidences a copper modification through Nb2O5. Results of diffuse reflectance spectra also evidenced the interaction. The catalytic tests showed that the niobium oxide dispersion on alumina improved the catalyst action; the ternary catalysts are the ones that show higher hydrogen production. They also produce ethyl ether as side product. The binary catalysts don't present parallel reaction, probably because when Cu/Nb2O5 is dispersed on alumina there is another type of catalytic site production, which produces ethyl ether.