DENITRIFICATION CATALYST AND DENITRIFYING METHOD USING THE SAME

摘要

PURPOSE: To provide a denitrification catalyst with which NOx in the exhaust gas from an inner combustion engine with a lean air-fuel ratio can be efficiently removed at an enough high gas space velocity, and to provide a denitrifying method using this catalyst showing high efficiency and high reliability to remove NOx in the exhaust gas from an inner combustion engine. CONSTITUTION: This catalyst is used to remove nitrogen oxides in exhaust gas of hydrocarbons in an oxygen-rich atmosphere. The catalyst consists of an alumina-titania carrier with deposition of silver and/or silver oxide. This alumina-titania catalyst is obtd. by adding titania to active alumina having >=120m<2> /g specific surface area, >=0.60g/cc balk density and <=1.80g/cc intrinsic density measured by a mercury pressurizing method. The denitrifying method for the exhaust gas from an inner combustion engine driven at a lean air-fuel ratio is carried out by allowing the exhaust gas to pass and touch through a denitrification catalyst layer. In this method, the catalyst is used as the catalyst constituting the denitrification catalyst layer.