Rare earth metal modified CuO/γ-Al2O3 catalysts in the CO oxidation

The nano-support γ-Al2O3 was prepared by chemical precipitation and combined with supercritical CO2 drying. The products were characterized by XRD diffraction, N2 physical adsorption–desorption, and transmission electron microscope (TEM) analysis. The supercritical CO2 drying method inhibited the agglomeration of particles and increased the sample's surface area. The rare earth metal modified CuO/Al2O3 catalysts were prepared by an impregnation method, and the catalytic activity for CO oxidation was investigated. Catalyst particles containing 3–4 components gave excellent catalytic activity. Lanthanum modified CuO/γ-Al2O3 catalysts show a significant promoting effect and the catalytic activity is comparable to the Ce containing catalysts.

Graphical AbstractFigure optionsDownload as PowerPoint slideResearch Highlights
► Al2O3 nanoparticle sized support with loose aggregation and high specific surface area can be obtained by simple precipitation process and supercritical CO2 drying.
► The two component catalysts using Al2O3 as support were prepared by doping lanthanides on CuO/Al2O3. The CeO2–CuO/Al2O3 and La2O3–CuO/Al2O3 catalysts both show high synergistic catalytic activity for CO oxidation.
► The samples prepared by impregnating CuO supported on Al2O3 with lanthanide nitrate show higher catalytic activity compared with that obtained by co-impregnating Al2O3 with lanthanide nitrate and copper nitrate.