Preparation of Al2O3–CeO2 by Hydrothermal Method Supporting Copper Oxide for the Catalytic Oxidation of CO and C3H8

A series of Al2O3–CeO2 carriers were synthesized by hydrothermal method, and CuO/Al2O3–CeO2 catalysts were prepared by ultrasound-assisted impregnation for the catalytic oxidation of CO and C3H8. These prepared samples have been characterized by XRD, BET, TEM, XPS, and other techniques. The 15 wt % CuO/A1C1 catalyst exhibited the best catalytic activity, and the light-off temperatures (T50) of CO and C3H8 were 67 and 325 °C, respectively. XRD results showed that the dispersion of CuO on the catalyst surface was improved by the introduction of CeO2 into the CuO/Al2O3 catalyst. Besides, with the addition of CeO2 content, the specific surface area and pore volume of the sample gradually decrease. XPS results suggest that the synergistic effect (Ce3+ + Cu2+ ↔ Ce4+ + Cu+) is conducive to the generation of oxygen vacancies and improves the activity of the catalyst. Both H2-TPR and O2-TPD temperatures shift toward lower temperatures, indicating that redox reactions are more likely to occur. Finally, based on the results of in situ DRIFTS, the surface Cu+ species obtained from the reduction of Cu2+ play a crucial role in the catalytic oxidation of CO and C3H8.