| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an NOx removal catalyst excellent in catalyst characteristics, in particular, low temperature activity. <P>SOLUTION: The NOx catalyst includes a defective perovskite type composite oxide represented by formula (1), AB<SB>2</SB>O<SB>4</SB>(1), (wherein A represents an alkali earth metal, and B represents a rare earth element) and an alkali earth metal oxide. Substantially, only a diffraction pattern of the defective perovskite type composite oxide is detected in power X-ray diffraction. The alkali earth metal oxide has a crystallite diameter of not larger than 1 nm. A manufacturing method of the NOx removal catalyst includes the step of executing thermal decomposition of a brownmillerite-type composite oxide represented by formula (2), A<SB>3</SB>B<SB>4</SB>O<SB>9</SB>(2), (wherein A represents an alkali earth metal, and B represents a rare earth element). <P>COPYRIGHT: (C)2010,JPO&INPIT |
