| 摘要 |
<p>An exhaust gas purifying catalyst is constructed by laminating sequentially a first layer containing alumina, a second layer containing hydrocarbon adsorbent, and a third layer containing catalytic components on a monolithic support in which a cell sectional shape is a polygon. The second layer has a ratio Lmax/Lmin of a thickest portion (Lmax) at cell corner portions to a thinnest portion (Lmin) at cell flat portions in a range of 1 to 10, and has a thickness of 10 to 500 mu m. The catalyst can achieve the purification of HC, CO, and NOx with good balance, and improve the purification performance of cold HC by controlling a diffusion speed of the exhaust gases that pass through cells in a support and diffuse into a coating layer. <IMAGE></p> |
