Phosphorus resistant three-way catalyst
AssigneeBASF SE
InventorsFudong Liu, Michel Deeba
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Abstract
Described are three-way conversion (TWC) catalytic articles effective to abate hydrocarbons (HCs), carbon monoxide (CO), and nitrogen oxides (NOx) from an engine exhaust gas containing phosphorous impurities. The disclosed catalytic article has a layered catalytic material, wherein the first layer of the catalytic material is disposed directly on the substrate and a second layer is disposed on top of the first layer. The second layer includes phosphorus resistant materials that prevent catalytic poisoning of the catalytic article by the phosphorous impurities. In particular, the second layer includes a phosphorus trap material having an alkaline earth metal component and a rhodium component impregnated on a phosphorus-resistant support material.
Claims21
A TWC catalytic article, comprising:
- a catalytic material on a substrate, the catalytic material comprising a first layer disposed on the substrate and a second layer disposed on the first layer,
- wherein the second layer comprises:
- a phosphorous trap material comprising an alkaline earth metal component and a metal oxide, wherein the alkaline earth metal component is supported on the metal oxide or the alkaline earth metal component is in the form of a composite with the metal oxide, and
- a rhodium component impregnated on a phosphorus-resistant support material, wherein the phosphorus-resistant support material is a zirconia-based support material and comprises from 50 wt % to 99 wt % zirconia;
- and
- wherein the catalytic material is effective for three-way conversion to oxidize carbon monoxide and hydrocarbons and reduce nitrogen oxides.
Dependencies are inferred from the claim text.