Résumé
A Cu/CeO2/Al2O3 catalyst (6.6% Cu, 13.8% Ce) based on a structurally organized mesoporous alumina was prepared by a new single-step sol–gel method starting from Al butoxide and Ce and Cu stearates. The sample was characterized by N2 adsorption, XRD, TPR and Cu dispersion measurements and tested as catalyst for the SRM (methanol steam reforming) and OSRM (methanol autothermal reforming) reactions. The material showed a huge surface area (360m2g−1) and resulted to contain very dispersed CeO2 and CuO phases on a poorly crystalline alumina matrix. A highly dispersed Cu metallic phase was obtained after a reductive treatment with H2. Catalytic tests showed that the unreduced material was fairly active for the OSRM process, but the activity increases appreciably after the pre-reduction treatment. The activity for the OSRM process resulted high, in terms of hydrogen production rate, if compared with data on similar Cu/Ce/Al systems, but the activity for SRM, in the absence of oxygen was, on the other hand, very low. This behaviour was explained either considering the occurrence of H spillover or the CeO2 assisted oxidation of Cu to Cu+.