CO preferential oxidation in H2-rich stream over the CuO-MnOx mixed oxide catalysts prepared by a facile mechanochemical preparation method.

The CuMn samples with various CuO weight percentages were synthesized by the mechanochemical route. The catalytic activity of the prepared samples was determined in the preferential oxidation of CO process (CO-PROX) in the temperature range of 40–250 °C. According to the XRD results, the 5CuMn and 10CuMn samples exhibited the spinel phase in their structures. The spinel phase formation enhanced the CO adsorption active sites and modified the redox properties. The results indicated that the copper incorporation into the manganese oxide modified the catalytic activity and structural properties. The 5CuMn catalyst with the highest BET area (72.1 m2 g−1) possessed 96% CO conversion and 50% CO 2 selectivity at 70 °C (GHSV = 30,000 ml/h.g cat) and significant resistance in the presence of water due to the formation of hydroxyl groups over the catalyst surface. The catalyst activity remained stable for 14 h at 130 °C. Furthermore, the influence of calcination temperature, feed composition, and GHSV value on the catalytic performance of the 5CuMn catalyst was studied. • The Cu–Mn catalyst with 5 wt% Cu exhibited a CO conversion higher than 90% at 70 °C. • 5 wt%. CuO-MnOx showed a Cu 1.5 Mn 1.5 O 4 spinel structure. • 5 wt%. CuO-MnOx catalyst exhibited sufficient stability in the presence of water vapor. [ABSTRACT FROM AUTHOR]