abstract |
Exhaust emission control catalysts capable of efficiently removing nitrogen oxide in exhaust containing a large amount of oxygen emitted from a diesel engine and the like and reducing the generation of particulate matter in the exhaust under high temperature conditions, and a method for controlling the emission of exhaust using the exhaust emission control catalysts. The exhaust emission control catalysts contain copper, praseodymium, and yttrium. The method for controlling the emission of exhaust purifies exhaust containing hydrocarbon and nitrogen oxide in a mole ratio (hydrocarbon/nitrogen oxide) within a range of 0.5 to 30 by bringing the exhaust into contact with the exhaust emission control catalysts. It is possible to efficiently remove nitrogen oxide in the exhaust by reduction while suppressing the oxidation of sulfur dioxide in the exhaust. |