| abstract |
The catalyst for purifying exhaust gas carries iridium as a catalytically active material, sulfur for improving the iridium catalytic activity, and, if necessary, platinum. The sulfur is preferably contained as lactic acid muscle. The exhaust gas purification method is a method for circulating the exhaust gas from an internal combustion engine to the exhaust gas purification catalyst by setting the exhaust gas temperature at the inlet of the exhaust gas purification catalyst to 200 to 700 ° C. The above constitution and method exhibit activity in a wide temperature range in exhaust gas purification, in particular in the removal of nitrogen oxides under an oxidizing atmosphere, and also have excellent heat resistance, durability and excellent practicality. |