Influence of the Interaction of Nickel and Copper with Ceria on Ethanol Steam Reforming over Ni-Cu-CeO[sub.2] Catalysts

Catalysts of nickel-ceria, nickel-copper-ceria, and copper-ceria were explored with respect to their properties for hydrogen production through ethanol steam reforming (ESR). They were prepared by coprecipitation of the components within inverse microemulsions to achieve intimate contact between them, and the catalysts were characterized by N[sub.2] adsorption measurements, XRD, Raman spectroscopy, TPR, and XPS. The catalysts were tested for the ESR reaction, and they were regenerated with oxygen when significant deactivation took place, as occurred for the copper-containing systems. In contrast, the nickel–ceria catalyst exhibits a high activity and stability despite the formation of an important amount of carbon deposits during the course of the ESR test. The presence of nickel sites, which strongly interact with the ceria support, and which are affected by the presence of copper, and the limitation of copper for C-C bond breaking are invoked to explain the results obtained on the whole.