| 摘要 |
PURPOSE: To prevent the specific surface area of a carrier from being lowered at time of high temperature and to highly maintain the NOx storing capacity of NOx storing material. CONSTITUTION: This catalyst for purifying exhaust gas is composed of a carrier consisting of zirconium phosphate, at least one kind of NOx storing material selected from alkali metals, alkaline earth metals and rare earth elements carried on the carrier and catalytic noble metals carried on the carrier. In zirconium phosphate, heat resistance is high in itself and reaction with the NOx storing material is not caused. Since zirconium phosphate is an acidic oxide, SOx as an acidic oxide is kept away from it and sulfur poisoning is prevented. |
