| 摘要 |
The invention relates to new compositions based on a mixed cerium and zirconium oxide (solid solutions) having very high specific surfaces, that is to say at least greater than 80 m<2>/g and preferably of at least 100 m<2>/g or even 150m<2>/g, the said surfaces moreover being thermally stable. The amounts of zirconium in solid solution in the cerium oxide can be very large, for example between 1 and 60 atom %. They are obtained according to a process consisting in heating an aqueous mixture containing, in the required stoichiometric proportions, a soluble cerium compound, such as ceric nitrate, and a soluble zirconium compound, such as zirconyl nitrate, in recovering, especially by filtration, the reaction product thus formed and then finally, optionally, in calcining this product. The compositions according to the invention can be used as catalysts and/or catalyst supports (substrates), in particular in the field of automobile afterburning. <IMAGE> |
