OXIDE CATALYST MATERIAL FOR REMOVING NITROGEN OXIDE AND NITROGEN OXIDE REMOVING METHOD

摘要

PURPOSE:To provide an oxide catalyst having high NOX reductive decomposition action under a high oxygen concn. atmosphere containing steam and purifying a harmful substance such as exhaust gas of an internal combustion engine of every kind. CONSTITUTION:As an oxide catalyst material for removing nitrogen oxide such as NOX or the like, composite oxide whose main crystal phase is a spinnel structure containing Ni and Ga as main metal elements and characterized in that the count ratio of Ga to Ni by fluorescent X-ray analysis is 1.4 or more is used. This oxide catalyst material is brought into contact with exhaust gas containing nitrogen oxide in an oxidizing atmosphere wherein oxygen is present in high concn. and reductive gas such as hydrocarbon is present to remove nitrogen oxide by reductive decomposition.