| 摘要 |
A NOx abatement composition comprises a NOx abatement catalyst and a NOx sorbent material which are dispersed in proximity to, but segregated from, each other on a common refractory carrier member (10). The NOx sorbent material comprises a basic oxygenated metal compound and optionally further comprises ceria. The NOx abatement catalyst contains a catalytic metal component including a platinum metal catalytic component. The catalytic metal component is segregated from the NOx sorbent material, which may be one or more of metal oxides, metal carbonates, metal hydroxides and mixed metal oxides. At least the catalytic metal component and the NOx sorbent material must be on, or comprise separate, particles; the particles may either be admixed or may be disposed in separate layers (20a, 20b) on the carrier member (10). A NOx abatement method employs the composition and includes periodically adjusting the gas being treated between lean and stoichiometric/rich operating cycles.
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