| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a ceria-zirconia-based compound oxide having superior characteristics as a cocatalyst in emission gas purifying catalyst used near to engines, and its manufacturing method. <P>SOLUTION: The ceria-zirconia-based compound oxide is manufactured by performing a first stage of preparing an acid solution containing cerium (III) ions and zirconium ions, a second stage of oxidizing the cerium (III) ions to cerium (IV) ions by adding a peroxodisulfate to the acid solution, a third stage of preparing a slurry solution of cerium sulfate and zirconium sulfate by heating the solution containing the cerium (IV) ions and unreacted peroxodisulfate, a fourth stage of preparing cerium-zirconium-based hydroxide slurry by adding a base to the slurry solution prepared in the third stage, a fifth stage of subjecting the hydroxide slurry to solid-liquid separation, followed by washing, drying and firing. <P>COPYRIGHT: (C)2008,JPO&INPIT |
