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

Abstract

Powders in the ZrO₂-M_xO_y and [20CeO₂-80ZrO₂ (mol%)]-M_xO_y system were prepared from zirconium sulfated slurry. The components M_xO_y are 1-16 groups of metal oxides in the Periodic Table including transition and rare earth. The influence of M_xO_y 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.