Optimized CuO-CeO2 catalysts for COPROX reaction

F. MARIÑO, G. BARONETTI, M. LABORDE, A. LE VALANT, N. BION, F. EPRON, D. DUPREZ

INTERNATIONAL JOURNAL OF HYDROGEN ENERGY

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Elsevier; Año: 2008 vol. 33 p. 1345 - 1353

0360-3199

CuO2CeO2 catalyst precursors were synthesized by homogeneous thermal decomposition of urea. Catalysts containing different Cu/Ce ratios were obtained after calcination of the precursors at 450 _C and characterized by ICP-OES, N2 adsorption, XRD and TPR. Catalytic tests were performed in the temperature range 1002300 _C to evaluate the activity of these samples for the COPROX reaction. A strong synergy between Cu and Ce is evidenced by the difference in the catalytic activity of the individual oxides (CuO and CeO2), a mechanical mixture of both oxides and a Cu–Ce mixed catalyst. The synergy between Cu and Ce is confirmed by the improvement of the reducibility of both cations in the mixed samples. Nitric acid and ammonium carbonate washed catalysts, especially high-copper-content samples, are more active than the untreated catalysts suggesting that the washing procedure could provoke a destruction of the polycrystalline structure that improves the contact between the reactants and the catalytic sites