| 摘要 |
PROBLEM TO BE SOLVED: To provide a catalyst apparatus for cleaning an exhaust gas wherein an NOx reduction catalyst is used so as to exhibit a high rate of cleaning NOx. SOLUTION: In a catalyst apparatus for cleaning an exhaust gas disposed in an exhaust passage and provided with an NOx reduction catalyst 5 carrying a noble metal that reductively detoxifies NOx, provision is made for a means disposed upstream of the NOx reduction catalyst 5 and forming channeling in the flow of an exhaust gas in the exhaust passage. The NOx reduction catalyst 5, when viewed from its upstream side, is formed so that the density of a carried novel metal may be higher in a first region 5a coming into contact with the exhaust gas in a relatively large amount per unit time and per unit area than in a second region 5b coming into contact with the exhaust gas in a relatively small amount. |
