| 摘要 |
Described are ZPGM catalyst systems which are free of any platinum group metals for reducing emissions of carbon monoxide, nitrogen oxides, and hydrocarbons in exhaust streams. ZPGM catalyst systems may include a substrate, a washcoat, and an overcoat. Both manganese and copper may be provided as catalysts, with copper in the overcoat and manganese preferably in the washcoat. The manganese can also be provided in the overcoat, but when in the overcoat should be stabilized for greatest effectiveness. A carrier material oxide may be included in both washcoat and overcoat. It has been discovered that the ZPGM catalyst systems are effective even without OSM in washcoat and the ZPGM catalysts within washcoat and overcoat may be best prepared by co-milling an aqueous slurry that includes manganese with alumina for the washcoat and copper and cerium salts with alumina and an OSM, for overcoat prior to overcoating and heat treating. Disclosed ZPGM TWC systems in catalytic converters may be employed to decrease the pollution caused by exhaust from various sources, such as automobiles, utility plants, processing and manufacturing plants, airplanes, trains, all-terrain vehicles, boats, mining equipment, and other engine-equipped machines. |
| 主权项 |
1. An apparatus for reducing emissions from an engine having associated therewith an exhaust system, the apparatus providing a reaction effective for selective catalytic reduction, comprising:
at least one source of exhaust comprising hydrocarbons and carbon monoxide; and a catalyst system, comprising:
a substrate;a catalyst;a washcoat suitable for deposition on the substrate; andan overcoat suitable for deposition on the substrate or the washcoat;wherein the catalyst comprises about 10% to about 16% by weight of copper, about 12% to about 20% by weight of cerium, and about 5% to about 10% by weight of manganese; andwherein the catalyst is suitable for deposition on a coat selected from the group consisting of at least one of the washcoat and the overcoat. |
