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Numerical Modeling of NO Reduction Over Cu-ZSM-5 Under Lean Conditions
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Abstract
Some catalysts such as copper zeolites have shown promise for direct NO decomposition and selective NO reduction via hydrocarbons in lean exhausts. This paper describes modeling calculations for the performance of a Cu-ZSM-5 NOx reduction catalyst. The numerical model simulates the multi-component transport and reaction processes that occur within a catalyzed monolith support. The surface boundary conditions for the reacting species are satisfied through use of multi-dimensional Newton-Raphsson iteration. The model is used to formulate global rate expressions for the oxidation of C3H6 and the reduction of NO by adjusting kinetic parameters until predicted conversion efficiencies match experimental data. Then the numerical model is compared to data from higher space velocities to test the validity of the kinetic model. The comparison at higher space velocity shows reasonable agreement, although additional optimization of the kinetic parameters is possible. The simulated interactions within the catalytic passage demonstrate important features of the selective NO reduction and show that optimal lean NOx catalyst performance may require high transport rates of the reductant species to the catalyst surface.
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Citation
Boehman, A., "Numerical Modeling of NO Reduction Over Cu-ZSM-5 Under Lean Conditions," SAE Technical Paper 970752, 1997, https://doi.org/10.4271/970752.Also In
Diesel Engine Combustion Processes and Emission Control Technologies
Number: SP-1246; Published: 1997-02-24
Number: SP-1246; Published: 1997-02-24
References
- Heywood, J. B. Internal Combustion Engines McGraw-Hill New York, NY 581 585 1988
- Iwamoto, M. Hamada, H. “Removal of Nitrogen Monoxide from Exhaust Gases Through Novel Catalytic Processes,” Catal. Today 10 57 71 1991
- Cho, B. K. “Nitric Oxide Reduction by Hydrocarbons over Cu-ZSM-5 Monolith Catalyst under Lean Conditions: Steady-State Kinetics,” J. Catal. 142 418 429 1993
- Feeley, J. S. Deeba, M. Farrauto, R. J. “Abatement of NO x from Diesel Engines: Status and Technical Challenges,” SAE Paper 950747 1995
- Li, Y. Armor, J. N. “Selective Catalytic Reduction of NO x with Methane over Metal Exchanged Zeolites,” Appl. Catal. B:Environ. 2 239 256 1993
- Zhang, X. Waiters, A. B. Vannice, M. A. J. Catal. 146 568 578 1994
- Konno, M. Chikahisa, T. Iwamoto, M. “Catalytic Reduction of NO x in Actual Diesel Engine Exhaust,” SAE Paper 920091 1992
- Cho, B. K. “Nitric Oxide Reduction by Ethylene over Cu-ZSM-5 under Lean Conditions: Study of Reaction Dynamics by Transient Experiments,” J. Catal. 155 184 195 1995
- Boehman, A. L. Niksa, S. Moffat, R. J. “Catalytic Oxidation of Carbon Monoxide in a Large Scale Planar Isothermal Passage,” SAE 922332 1992
- Narula, C. K Allison, J. E. Bauer, D. R. Gandhi, H. S. “Materials Chemistry Issues Related to Advanced Materials Applications in the Automotive Industry,” Chem. Mater. 8 984 1003 1996
- Boehman, A. L. Simons, J. W. Niksa, S. McCarty, J. G. “Dynamics Stress Formation During Catalytic Combustion of Methane in Ceramic Monoliths,” Comb. Sci. Tech. 1996
- Press, W. H. Flannery, B. P. Teukolsky, S. A. Vetterling, W. T. Numerical Recipes University of Cambridge Press Cambridge, UK 269 273 1986
- Boudart, M. Djéga-Mariadassou, G. Kinetics of Heterogeneous Catalytic Reactions Princeton University Press Princeton, NJ 90 105 1984
- Voltz, S. E. Morgan, C. R. Liederman, D. Jacob, S. M. “Kinetic Study of Carbon Monoxide and Propylene Oxidation on Platinum Catalysts,” Ind. Eng. Chem. Prod. Res. Develop. 12 294 301 1973
- Oh, S. H. Cavendish, J. C. Transients of Monolithic Catalytic Converter: Response to Step Changes in Feedstream Temperature as Related to Controlling Automobile Emissions,” Ind. Eng. Chem. Prod. Res. Develop. 21 29 37 1982
- Oh, S. H. Fisher, G. B. Carpenter, J. E. Goodman, D. W. “Comparative Studies of CO-O 2 and CO-NO Reactions over Single Crystal and Supported Rhodium Catalysts,” J. Catal. 100 360 376 1986
- Kee, R. J. Miller, J. A. Jefferson, T. H. “CHEMKIN: A General-Purpose, Problem-Independent, Transportable, Fortran Chemical Kinetics Code Package,” Sandia Report SAND80-8003 1980