EXHAUST GAS PURIFYING CATALYST

摘要

PURPOSE:To further improve NOx cleaning function and prevent sintering of palladium by further improving a three-dimensional catalyst for which palladium is used. CONSTITUTION:Palladium, alkaline earth metals, and platinum are contained as catalytically active components and more palladium is contained than platinum (Pt<=Pd) by weight conversion. The balance between the properties of palladium which has excellent three dimensional activity near theoretical air-fuel ratio and the properties of platinum which has excellent NOx cleaning function in lean atmosphere becomes the optimum and the NOx cleaning function near the theoretical air-fuel ratio and in the lean atmosphere side is improved.