Catalytic combustion of hydrocarbons with Mn and Cu-doped ceria-zirconia solid solutions

The catalytic activity of a series of CeO2-ZrO2 mixed oxides in the total oxidation of methane and light hydrocarbons has been investigated. The influence of dopants like Mn and Cu has also been studied. It is shown that both MnOx and CuO at low loading dissolve within the ceria-zirconia lattice. This strongly influences the redox behaviour of the catalysts by promoting low-temperature reduction of Ce4+. In addition, the ternary oxides show better stability to repeated redox cycles, which is attributed to the presence of ZrO2. The catalytic activity of pure CeO2 is also enhanced in the presence of ZrO2, reaching a maximum with Ce0.92Zr0.08O2; a further promotion of activity is observed with the introduction of MnOx and CuO dissolved into CeO2-ZrO2 lattice.