| abstract |
A catalyst and a method for selectively reducing nitrogen oxides ('NOx') with ammonia are provided The catalyst includes a first component comprising a zeolite or mixture of zeolites a second component comprising at least one member selected from the group consisting of cerium, iron, copper, gallium, manganese, chromium, cobalt, molybdenum, tin, rhenium, tantalum, osmium, banum, boron, calcium, strontium, potassium, vanadium, nickel, tungsten, an actinide, mixtures of actinides, a lanthanide, mixtures of lanthamdes, and mixtures thereof, optionally an oxygen storage mateπal and optionally an inorganic oxide The catalyst selectively reduces nitrogen oxides to nitrogen with ammoma at high temperatures The catalyst has high hydrothermal stability The catalyst has high activity for conversion of low levels of nitrogen oxides in exhaust streams |