High performance and stability of copper loading on mesoporous ceria catalyst for the preferential oxidation of CO

Abstract

Copper (Cu) doped mesoporous (MSP) ceria catalysts with different Cu dopings were prepared by deposition-precipitation (DP) method for the preferential CO oxidation in a H₂- rich stream (CO-PROX). The synthesized MSP ceria presents the higher surface area of 293.2 m²/g and more ordered structure than commercial ceria All copper-MSP ceria catalysts show high dispersion of Cu, long-range order of three dimensional pore structure and still maintain fluorite structure of MSP ceria. Moreover, the reduction temperature of the Cu-catalysts shift to the lower temperature comparing to pure MSP ceria and the reduction of Ce⁴⁺ to Ce³⁺ is decreasing when increasing the copper content. The MSP ceria catalyst with 7 wt% Cu loading (7Cu/MSP ceria) shows the highest activity at 110 ℃ with 100% CO conversion, and the temperature at 100 % CO conversion shifts to 130 ℃ in the presence of CO₂ and H₂O Moreover, the 7Cu/MSP ceria also performs the high stability over 48 h in various feed components which is attractive for using as a catalyst in purification of hydrogen due to the slight change of the fluorite structure and surface composition after PROX reaction.