EXHAUST GAS PURIFYING CATALYST AND PURIFYING METHOD

摘要

PROBLEM TO BE SOLVED: To provide an exhaust gas purifying catalyst excellent in utility, which has an excellent NOx removing performance and durability even in an exhaust gas containing sulfur oxide, and in which a denitrifying performance is not reduced even at relatively low exhaust gas temperatures in the range of about 300°C to 400°C, and an exhaust gas purifying method using the same.

SOLUTION: A proton type β zeolite is used as a catalyst and contacts with an exhaust gas with a superfluous oxygen in the presence of ethanol and/or isopropyl alcohol as a reducing agent to reduce and remove a nitrogen oxide NOx from the exhaust gas. A SiO2/Al2O3molar ratio of the proton type β zeolite, an exhaust gas purifying catalyst, is preferably 20-70.

COPYRIGHT: (C)2004,JPO&NCIPI