METHOD AND CATALYST FOR TREATING GAS COMBUSTION EXHAUST GAS

PURPOSE:To simultaneously and efficiently remove nitrogen oxide, lower hydrocarbon and CO in exhaust gas with a single catalyst by catalytically reacting gas combustion exhaust gas generated under a condition wherein the ratio of raw material gas and air becomes the lean side of the raw material gas in the presence of a catalyst obtained by loading a metal such as Co or the like on a mordenite type zeolite carrier. CONSTITUTION:Gas combustion exhaust gas generated under such a condition that the ratio of raw material gas and air becomes the lean side of the raw material gas and containing nitrogen, oxygen, steam and CO2 as principal components and lower hydrocarbon, especially, methane, nitrogen oxide and CO as small amount components is catalytically reacted in the presence of a catalyst obtained by making a mordenite type zeolite carrier carry a metal selected from Co, Mn, Rh, platinum and Pd. As a result, a small amount of nitrogen oxide, lower hydrocarbon, especially, methane and CO contained in the gas combustion gas containing a relatively large amount of oxygen and steam at the same time in a gas engine can be simultaneously and efficiently removed using the single catalyst.