| abstract |
(57) [Summary] [Objective] A method for purifying exhaust gas containing nitrogen oxides, carbon monoxide, and hydrocarbons. A method for reducing nitrogen oxides to nitrogen by contacting nitrogen oxides with a catalyst together with a reduced product, wherein the catalyst uses iridium as an active metal, and the reduced product is kerosene, light oil, gasoline or the above. An exhaust gas purification method, wherein fuel is converted into hydrocarbon containing a large amount of aromatic or olefin components by thermal decomposition or catalytic decomposition. |