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New Insights into the Unique Operation of Small Pore Cu-Zeolite SCR Catalyst: Overlapping NH3 Desorption and Oxidation Characteristics for Minimizing Undesired Products
ISSN: 0148-7191, e-ISSN: 2688-3627
Published April 01, 2014 by SAE International in United States
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An operational challenge associated with SCR catalysts is the NH3 slip control, particularly for commercial small pore Cu-zeolite formulations as a consequence of their significant ammonia storage capacity. The desorption of NH3 during increasing temperature transients is one example of this challenge. Ammonia slipping from SCR catalyst typically passes through a platinum based ammonia oxidation catalyst (AMOx), leading to the formation of the undesired byproducts NOx and N2O. We have discovered a distinctive characteristic, an overlapping NH3 desorption and oxidation, in a state-of-the-art Cu-zeolite SCR catalyst that can minimize NH3 slip during temperature transients encountered in real-world operation of a vehicle. In this work we show new insights, gained from NH3 temperature programmed desorption and oxidation experiments, into the Cu-zeolite catalyst functions responsible for the overlap of NH3 desorption and oxidation characteristics and the impact of hydrothermal treatment on these functions.
CitationKamasamudram, K., Kumar, A., Luo, J., Currier, N. et al., "New Insights into the Unique Operation of Small Pore Cu-Zeolite SCR Catalyst: Overlapping NH3 Desorption and Oxidation Characteristics for Minimizing Undesired Products," SAE Technical Paper 2014-01-1542, 2014, https://doi.org/10.4271/2014-01-1542.
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