Hydrogen production through alcohol steam reforming on Cu/ZnO-based catalysts

Hydrogen production by steam reforming of methanol and ethanol is studied over a series of Cu/ZnO/Al2O3 catalysts prepared by different coprecipitation procedures and modified with the introduction of Ni and Co. The catalysts are characterized using N2 physisorption, X-ray diffraction (XRD), temperature programmed reduction (TPR) techniques, N2O decomposition, high resolution transmission electron microscopy (HR-TEM) and thermogravimetric analysis (TGA). Despite the influence of the preparation method on the texture and structure of Cu/ZnO/Al2O3 catalysts, their catalytic behavior appears not significantly affected. While Cu/ZnO/Al2O3 shows poor H2 selectivity in the ethanol steam reforming reaction, the presence of a second metal (Ni or Co) significantly improves the reforming reaction. Although coke deposition remains a drawback for these systems, formation of an alloy between Ni and Cu appreciably reduces carbon deposition with respect to the Co/Cu-based system.