| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a catalyst for cleaning exhaust gas capable of exhibiting excellent NO<SB>X</SB>adsorption performance even after duration, and to provide a production method thereof. <P>SOLUTION: The catalyst for cleaning exhaust gas is an orthorombic complex compound which comprises noble metal, porous body and Ba<SB>X</SB>Sr<SB>1-X</SB>CO<SB>3</SB>and has the spacing d of (111) plane of the Ba<SB>X</SB>Sr<SB>1-X</SB>CO<SB>3</SB>satisfying d=3.63±0.07 Å in X-ray diffraction measurement in the case of heating the catalyst for cleaning exhaust gas from ≥500 to <800°C and cooling the catalyst to the ordinary temperature. The crystallite diameter of the Ba<SB>X</SB>Sr<SB>1-X</SB>CO<SB>3</SB>is ≤40 nm. The catalyst for cleaning exhaust gas is produced by depositing the noble metal to the porous body and impregnating a mixed aqueous solution including Ba and Sr into the noble metal-carrying porous body. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
