摘要 |
The object is to provide an exhaust gas purification catalyst that exhibit high nitrogen oxide purification performance, and to provide a simple and efficient method for producing the catalyst, in which the amount of the waste liquid is reduced, further, an object of the invention is to provide a zeolite-containing catalyst for purifying nitrogen oxides, which does not use an expensive noble metal or the like and which has high nitrogen oxide purification performance. The present invention relates to a catalyst for purifying nitrogen oxides, which comprises: zeolite at least containing an aluminium atom and a phosphorus atom in the skeleton structure thereof; and a metal supported on the zeolite, wherein a fluctuation coefficient of intensity of the metal is at least 20%, when performing an element mapping of the metal in the catalyst with an electron probe microanalyzer, and, a catalyst for purifying nitrogen oxides, which comprises the zeolite containing at least a silicon atom, a phosphorus atom and an aluminium atom, and having an adsorption retention rate of at least 80% in a water vapor repetitive adsorption/desorption test at 90°C. |