CO preferential oxidation reaction aspects in a nanocrystalline CuO/CeO2 catalyst

CuO/CeO2 catalysts were prepared by the Pechini method and applied in the CO preferential oxidation (CO-PROX). The CuO content effects on the catalysts and the presence of H2O and CO2 in the reaction stream on the catalytic performance were investigated. The catalyst with 1.0 wt.% CuO presented the highest conversion and selectivity in the COPROX in the temperature range 100–250 °C. It was observed that the catalytic system is sensitive to the dispersion of the active phase and, independently of the copper content, the high activity of the CuO/CeO2 catalysts is closely related to the finely dispersed CuO species strongly interacting with CeO2 support. In the long-term stability test under the real CO-PROX condition with 10 mol% H2O and 15 mol% CO2 in the reactant stream, about 90% CO conversion can be maintained even at low temperature (150 °C) with 95% selectivity.