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Reactions Over A Double Layer Tri-Metal Three-Way Catalyst
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Abstract
The reactions over a commercially available double layer tri-metal type (Pt, Pd, Rh) passenger car catalyst were analysed. A parameter study was performed in synthetic exhaust gases at: steady state conversion, periodic oscillations, and controlled transients. The influences of gas phase composition, temperature, adiabatic heat of reaction and lambda oscillations were investigated. The reactions of nitrogen oxides, propene and carbon monoxide were simultaneously analysed. Fast response emission analysers were used to record the dynamic properties of the catalysts.
The catalyst was found to have high conversion rates and high oxygen storage capacity at relatively low temperatures. The presence of sulphur dioxide was found to reduce the conversion of CO and NOx substantially. An emission increase of 40-70 % was observed for steady state conditions and at oscillating conditions the increase was more than 100%. The experimental results were simulated in a dynamic model and a simplified reaction mechanism which explained the differences was proposed. The implications for catalyst diagnostics were discussed.
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Jobson, E., Hjortsberg, O., Andersson, S., and Gottberg, I., "Reactions Over A Double Layer Tri-Metal Three-Way Catalyst," SAE Technical Paper 960801, 1996, https://doi.org/10.4271/960801.Also In
References
- Shelef M. Graham G.W. “Why Rhodium in automotive three-way catalysis” Catal. Rev. Sci. Eng. 36 3 433 457 1994
- Nieuwenhuys B.E. Sierra J. Tanaka K-i. Hirano H. “Differences in behaviour of Pt, Rh and Pt-Rh alloy surfaces toward NO reduction” Environmental Catalysis, chpt 10 American Chemical Society 1994
- Burch R. Millington P.J. Walker A.P. “Mechanism of the selective reduction of nitric oxide by propene on platinum-based catalysts in the presence of excess oxygen” Symp on NO x red. 207th National Meeting American Chemical Society San Diego March 13-18 1994
- Muraki H. Sobukawa H. Kimura M. Isogai A. “The effect of palladium on the performance of three-way catalyst” SAE 900610
- Schweich D. “Flow heat and mass transfer in a monolithic catalytic reactor” Catalysis and Automotive Pollution Control II; Proceedings Elsevier 1991 437
- Leclerc J.P. Schweich D. Villermaux J. “A new theoretical approach to catalytic converters” Catalysis and Automotive Pollution Control II; Proceedings Elsevier 1991 465
- Jobson E. Smedler G. Malmberg P. Bernler H. Hjortsberg O. Gottberg I. Rosén Å. “Nitrous oxide formation over three-way catalysts” SAE 940926
- Jobson E. Laurell M. Högberg E. Bernler H. Lundgren S. Wirmark G. Smedler G. “Deterioration of three-way Automotive Catalysts, Part 1 Steady State and Transient Emissions of Aged Catalysts” SAE 930937
- Schlatter J.C. Taylor K. “Platinum and Palladium addition to supported Rhodium catalysts for automotive emission control” J.Catal. 49 42 50 1977
- Monroe D.R. Krueger M.H. Beck D.D. D'Aniello M.J. Jr. Catalysis and Automotive Pollution Control II; Proceedings Elsevier 1991 593
- Hepburn J.S. Dobson D.A. Hubbard C.P. Guldberg S.O. Thanasiu E. Watkins W.L. Burns B.D. Gahndi H.S. “A review of the dual EGO Sensor Method for OBD-II Catalyst Efficiency Monitoring” SAE 942057
- Iguchi S. Kihara T. Harada J. Tanaka T. Katoh K. “NO x storage reduction 3-way catalyst for lean burn system” Fortschrittberichte, 16 Internationales Wiener Motorensymposium 1995 249
- Yamada T. Kayano K. Funabiki M. ‘Platinum metals-ceria synergism in autoexhaust catalyst” New Aspects of Spillover Effect in Catalysis Elsevier 1993 329
- Lundgren S. Spiess G. Hjortsberg O. Jobson E. Gottberg I. Smedler G. “Sulphur adsorption and desorption on fresh and aged Ce containing catalysts” Studies in surface science and catalysis 96 1995 763
- Golunski S.E. Hatcher H.A. Rajam R.R Truex T.T. “Origins of low-temperature three-way activity in Pt/CeO 2 ” Appl.Catal. B: Environmental 5 1995 367 376
- Shelef M. Gahndi H.S. Ind.Eng.Chem.Proc.Res. Dev. 8 393 1972