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A Comparison of Conversion Efficiencies of Individual Hydrocarbon Species Across Pd- and Pt-Based Catalysts as a Function of Fuel-Air Ratio
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Abstract
Individual hydrocarbon conversion efficiencies of engine-out emissions have been measured for four different catalyst formulations (Pd-only, trimetallic, Pd/Rh, and Pt/Rh) during stoichiometric and rich operation. The measurements were carried out as a function of fuel-air equivalence ratio (Φ) using a dynamometer-controlled 1993 Ford V8 engine and capillary gas chromatography. HC conversion efficiency was examined in terms of mass conversion efficiency and also using three new definitions of catalyst conversion efficiency. The efficiencies across the four catalysts show similar trends with Φ for almost all HC species. The catalyst efficiencies for alkanes, alkenes, and aromatic species decrease as Φ increases above stoichiometric: alkane efficiencies decrease faster than alkenes which in turn decrease faster than aromatics. All efficiencies fall to zero near Φ = 1.08 except those of MTBE and acetylene, which remain near 100%. The formaldehyde efficiency decreases from 92% at Φ = 1.0 to 78% at Φ= 1.068 for all Pd-based catalyst technologies
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Siegl, W., Kaiser, E., Adamczyk, A., Guenther, M. et al., "A Comparison of Conversion Efficiencies of Individual Hydrocarbon Species Across Pd- and Pt-Based Catalysts as a Function of Fuel-Air Ratio," SAE Technical Paper 982549, 1998, https://doi.org/10.4271/982549.Also In
Taking Gasoline Vehicles Beyond Ulev: Catalyst System Approaches
Number: SP-1392; Published: 1998-10-19
Number: SP-1392; Published: 1998-10-19
References
- Cadle, S. H. Gorse, R. A. Carlock, M. Knapp, K. T. Cullen, K. Lawson, D. R. “Real-World Vehicle Emissions: A Summary of the Fourth Annual CRC-APRAC On-Road Vehicle Emissions Workshop,” J. Air Waste Manage. Assoc. 44 1180 1994
- Kelly, N. A. Groblicki, P. J. “Real-World Emissions from a Modern Production Vehicle Driven in Los Angeles,” J. Air Waste Manage. Assn. 43 1351 1993
- Denis, M. J. St. Cicero-Fernandez, P Winer, A. M. Butler, J. W. Jesion, G. “Effects of In-Use Driving Conditions and Vehicle/Engine Operating Parameters on “Off-Cycle” Events: Comparison with Federal Test Procedure Conditions,” J. Air Waste Manage. Assn. 44 31 1994
- “Proposed Regulations for Low-Emission Vehicles and Clean Fuels - Staff Report and Technical Support Document,” California Air Resources Board Sacramento, CA 5 13 90
- Carter, W. P. L. “Development of Ozone Reactivity Scales for Volatile Organic Compounds,” J. Air Waste Manage. Assoc. 44 881 1994
- DiCicco, D. M. Adamczyk, A. A. Patel, K. S. “The Effect of Fuel Sulfur Level on the HC, CO, and NO x Conversion Efficiencies of Pd/Rh, Pt/Rh, Pd-Only, and Trimetal Catalysts,” 210th National Meeting of the American Chemical society Division of Fuel Chemistry Paper No. 145 1995
- Kaiser, E. W. Siegl, W. O. “High Resolution Gas Chromatographic Determination of the Atmospheric Reactivity of Engine-Out Hydrocarbon Emissions from a Spark-Ignited Engine,” J. High Resolution Chromatography 17 264 1994
- Siegl, W. O. Richert, J. F. O. Jensen, T. E. Schuetzle, D. Swarin, S. J. Loo, J. F. Prostak, A. Nagy, D. Schlenker, A. M. “Improved Emissions Speciation Methodology for Phase II of the Auto/Oil Air Quality Improvement Research Program. Hydrocarbons and Oxygenates.,” SAE Technical Paper No. 930142 Society of Automotive Engineers 1993
- Kaiser, E. W. Siegl, W. O. Henig, Y. I. Anderson, R. W. Trinker, F. H. “Effect of fuel structure on emissions from a spark ignited engine” Environ. Sci. & Technol. 25 2005 1991
- Kaiser, E. W. Rothschild, W. G. Lavoie, G. A. “The Effect of Fuel and Operating Variables on Hydrocarbon Species distributions in the Exhaust from a Multi-cylinder Engine,” Comb. Sci. Technol. 32 245 1983
- Pelz, N. Dempster, N. Hundleby, G. Shore, P. “The compsition of gasoline engine hydrocarbon emissions - an evaluation of catalyst and fuel effects,” SAE Technical Paper No. 902074 Society of Automotive Engineers 1990
- Dearth, M. A. Gierczak, C. A. Siegl, W. O. “On-line Measurement of Benzene and Toluene in Dilute Vehicle Exhaust by Mass Spectrometry,” Environ. Sci. Technol. 26 1573 1992
- Summers, J. C. Silver, R. G. “Catalytic Control Issues Associated with the Use of Reformulated Gasolines,” SAE Technical Paper No. 902072 Society of Automotive Engineers 1990
- Drake, M. C. Sinkevitch, R. M. Quader, A. A. Olson, K. L. Chapaton, T. J. “Effect of Fuel/Air Variations on Catalyst Performance and Hydrocarbon Emissions During Cold-Start and Warm-Up,” SAE Technical Paper No. 962075 Society of Automotive Engineers 1996
- Nagel, H. Frey, R. Hartgerink, C. Rikeit, H.-E Greiner, R.-D Klein, Ch. Boesl, U. “On-Line Analysis of Individual Aromatic hydrocarbons in Automotive Exhaust: Dealkylation of the Aromatic Hydrocarbons in the Catalytic Converter” SAE Paper No. 971606 Society of Automotive Engineers 1997