Methods for selecting and applying a layer of Cu—Mn spinel phase to ZPGM catalyst systems for TWC application

摘要

The present disclosure relates to selecting the layer of applying ZPGM active phase in washcoat, or applying ZPGM active phase in overcoat, for achieving optimized performance and enhanced thermal stability. Applying ZPGM active phase catalyst in overcoat shows improvements compare to applying ZPGM active phase in washcoat. The selected active phase material may include a chemical composition that is substantially free from PGM, including a formulation of stoichiometric Cu—Mn spinel structure active phase deposited on Niobium-Zirconium support oxide. The selected active phase layer applied in overcoat may include a washcoat of alumina coated on a suitable ceramic substrate. The disclosed active phase may be applied in overcoat to maximize efficiency of catalyst systems, which may exhibit enhanced catalytic activity properties, which may stable after aging and under steady state and oscillating condition, showing optimized performance purifying gases in TWC condition.

主权项

1. A method for optimizing a catalytic component, comprising:
applying to a substrate a first washcoat comprising AL203, applying to the substrate of a second washcoat or an overcoat having at least one active phase catalyst composition comprising Cu—Mn and a support oxide comprising Nb205-Zr02, wherein a loading of Cu—Mn in the catalyst composition is from 25 to 34%, and a loading of the Nb205-Zr02 in the catalyst composition is from 66 to 75%, based on a total loading of the catalyst composition.