Preparation of Mixed Oxide Powders in the Systems ZrO2-MxOy and [20CeO2-80ZrO2(mol%)]-MxOy from Zirconium Sulfated Slurry for the Purification Catalysts of Automotive Emission

Powders in the ZrO2-MxOy and [20CeO2-80ZrO2 (mol%)]-MxOy system were prepared from zirconium sulfated slurry. The components MxOy are 1-16 groups of metal oxides in the Periodic Table including transition and rare earth. The influence of MxOy addition on specific surface area (SA) and oxygen storage capacity (OSC) was investigated. It was found that, compared with additive-free powders, the powders containing La, Pr, Nd, Sm, Eu, Gd, Tb or Dy had high SA values at 1000°C. On the other hand, the powders containing V, Cr, Co, Ni or Cu had high OSC values at 610°C and 1000°C. It may be concluded that the powders containing rare earth metals show high SA values and those containing transition metals show high OSC values exhibiting high thermal stability.