High methane combustion activity of PdO/CeO₂–ZrO₂–NiO/γ-Al₂O₃ catalysts

PdO/CeO2–ZrO2–NiO/γ-Al2O3 catalysts were prepared for the combustion of methane at moderate temperatures. The introduction of a small amount of NiO within the cubic fluorite CeO2–ZrO2 structure as a promoter effectively enhanced the oxygen release and storage abilities of the catalysts, thereby achieving the complete oxidation of methane. The catalyst with the highest activity for methane combustion was 11.3 mass% PdO/20 mass% Ce0.64Zr0.16Ni0.2O1.9/γ-Al2O3, and efficient combustion was realized at a temperature as low as 300 °C.