| 发明名称 |
Exhaust gas purifying catalyst and method of preparing the same. |
| 摘要 |
<p>In order to obtain a three way catalyst having catalytic activity also at a temperature exceeding 900 DEG C as well as high purification ability with respect to NOx, a perovskite compound oxide which is expressed in a general formula Ln1-xAxMO3, where Ln represents one or at least two rare earth metals excluding Ce, A represents Ce or one or at least two alkaline earth metals, M represents one or at least two transition metals and 0<x<1, a heat resistant oxide containing Ce and Zr, or further containing a rare earth metal excluding Ce so that the same is at least partially in the form of a compound oxide or a solid solution, and a precious metal are coexistently mixed with each other. Heat resistance is improved by coexistence of the heat resistant oxide, while purification ability with respect to NOx is improved by coexistence of the precious metal. In order to obtain an exhaust gas purifying catalyst which exhibits sufficient purification activity also at a low exhaust gas temperature condition, a double structure is attained by a core of a perovskite compound oxide such as (La0.8Ce0.2) (Co0.4Fe0.6)O3 and an outer perovskite compound oxide, in which a precious metal is solidly dissolved, enclosing the core. When the precious metal is provided in excess, the excessive part thereof is dispersed in a fine particle state as a metal or an oxide.</p> |
| 申请公布号 |
EP0525677(A1) |
申请公布日期 |
1993.02.03 |
| 申请号 |
EP19920112717 |
申请日期 |
1992.07.24 |
| 申请人 |
DAIHATSU MOTOR COMPANY, LTD.;KABUSHIKI KAISHA TOYOTA CHUO KENKYUSHO |
发明人 |
TANAKA, HIROHISA;TSUBOI, HIDEFUMI;MATSUMOTO, SHINICHI;KIMURA, MAREO;SOBUKAWA, HIDEO;OZAWA, MASAKUMI |
| 分类号 |
B01D53/94;B01J23/00;B01J23/83;B01J23/89 |
主分类号 |
B01D53/94 |
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