| 摘要 |
<p>Disclosed is an exhaust purification catalyst in which the heat capacity of a downstream catalyst layer is larger than the heat capacity of an upstream catalyst layer, and the supporting capacity of noble metal in an upstream portion (high density portion) of the upstream catalyst layer is higher than the supporting capacity of noble metal in the other portion of the upstream catalyst layer. The flow- through support, such as a honeycomb soot filter, is loaded with catalyst, such as Pt, Pd, in decreasing amount from intake to outlet. Conversely, the thickness of the support layer of Pt, Pd, such as alumina particle, increases from inlet to outlet. Hence, the thermal capacity of the catalyst layer comprising catalyst and carrier particle is higher at the outlet /downstream end.</p> |
