| 摘要 |
<p>In a preferred method for treating diesel-fuelled engine exhaust to reduce emission of particulates having cores of carbonaceous material and condensable hydrocarbons deposited on the carbonaceous material, the condensable hydrocarbons in the exhaust are contacted with a catalytically-active solid acid material having hydrogen ions releasably retained at acidic sites thereof, and the condensable hydrocarbons in contact with the sites are cracked as hydrogen ions are released from the sites. The solid acid material is desirably a Y-type zeolite with hydrogen (H) cations (HY zeolite), or hydrolyzed multi-valent cations, such as lanthanum (LaY zeolite), cerium (CeY zeolite) and calcium (CaY zeolite), and is supported on a ceramic or metal monolith. The HY zeolite is preferred. The Y-type zeolite is conveniently mixed with washcoat precursor particles and applied as a layer on said monolith.</p> |
