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Hydrocarbon Reactivity in a Plasma-Catalyst System: Thermal Versus Plasma-Assisted Lean NOx Reduction
Technical Paper
2001-01-3565
ISSN: 0148-7191, e-ISSN: 2688-3627
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Sector:
Event:
Spring Fuels & Lubricants Meeting & Exhibition
SAE International Fall Fuels & Lubricants Meeting & Exhibition
Language:
English
Abstract
The steady-state reduction of NOx at temperatures between 150-300°C has been investigated under simulated lean-burn conditions using a two-stage transient flow reactor system consisting of non-thermal plasma in combination with a sodium Y zeolite catalyst. Reactivity comparisons were made with and without plasma operation in order to identify the plasma-generated hydrocarbon species necessary for the selective catalytic reduction (SCR) of NOx. With propene as the hydrocarbon in the feed, NO is completely oxidized to NO2 in the plasma and the formation of oxidized carbon-containing species include formaldehyde, acetaldehyde, carbon monoxide, carbon dioxide, and methanol. Fourier transform infrared (FTIR) measurements indicate a close carbon balance between plasma inlet and outlet gas feed concentrations, signifying the major species have been identified.
Plasma-assisted NOx conversion over the sodium Y zeolite catalyst is improved with supplemental acetaldehyde injection, primarily through the removal of NO from the feed stream. In addition, the thermal (no plasma) reduction of NO is much greater with acetaldehyde as the reductant compared to propene, demonstrating that the NOx reduction reaction is controlled by the acetaldehyde present in the gas feed. The thermal catalytic NOx conversion with acetaldehyde in a NO-containing feed is much higher than that in a NO2-containing feed, indicating that plasma conversion of NO to NO2 is not required for NOx reduction. The higher activity of NO is due to the increased formation of HCN, a partial reduction product that can be removed using a downstream Pt/Al2O3 catalyst. Octane, which is more representative of hydrocarbons found in diesel fuel/exhaust, forms acetaldehyde over the catalyst and yields comparable NOx reduction activity. At similar acetaldehyde concentration levels entering the catalyst, thermal NOx conversion with the feed containing NO and acetaldehyde is comparable to the plasma-assisted NOx conversion efficiency with the feed containing propene and NO, suggesting that an appropriate hydrocarbon can reduce NO without the use of non-thermal plasma.
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Citation
Schmieg, S., Cho, B., and Oh, S., "Hydrocarbon Reactivity in a Plasma-Catalyst System: Thermal Versus Plasma-Assisted Lean NOx Reduction," SAE Technical Paper 2001-01-3565, 2001, https://doi.org/10.4271/2001-01-3565.Also In
References
- Taylor K.C. “Nitric Oxide Catalysis in Automotive Exhaust Systems” Catal. Rev.-Sci. Eng. 35 4 457 481 1993
- Hoard J. “Plasma-Catalysis for Diesel Exhaust Treatment: Current State of the Art” SAE 2001-01-0185 2001
- Plasma Exhaust Aftertreatment SAE SP-1395 Hoard J. Servati H. Society of Automotive Engineers, Inc. Warrendale, PA 1998
- Herling D. Smith M. Baskaran S. Kupe J. “Application of Non-Thermal Plasma Assisted Catalyst Technology for Diesel Engine Emission Reduction” SAE 2000-01-3088 2000
- Aardahl C.L. Habeger C.F. Balmer M.L. Rappe K.G. Tran D.N. Avila M. Park P.W. Koshkarian K.A. Chanda A. “Plasma-Enhanced Catalytic Reduction of NO x in Simulated Lean Exhaust” SAE 2000-01-2961 2000
- Penetrante B.M. Brusasco R.M. Merritt B.T. Pitz W.J. Vogtlin G.E. Kung M.C. Kung H.H. Wan C.Z. Voss K.E. “Plasma-Assisted Catalytic Reduction of NO x ” SAE 982508 1998
- Balmer M.L. Tonkyn R. Kim A. Yoon S. Jimenez D. Orlando T. Barlow S.E. Hoard J. “Diesel NO x Reduction on Surfaces in Plasma” SAE 982511 1998
- Penetrante B.M. Brusasco R.M. Merritt B.T. Vogtlin G.E. “Sulfur Tolerance of Selective Partial Oxidation of NO to NO 2 in a Plasma” SAE 1999-01-3687 1999
- Herling D. Smith M. Hemingway M. Goulette D. Silvas T. “Evaluation of Corona Reactors of Several Geometries for a Plasma Assisted Nitrogen Oxide Emission Reduction Device” SAE 2000-01-2899 2000
- Tonkyn R. Yoon S. Barlow S.E. Panov A. Kolwaite A. Balmer M.L. “Lean NO x Reduction in Two-Stages: Non-Thermal Plasma Followed by Heterogeneous Catalysis” SAE 2000-01-2896 2000
- Fisher G.B. DiMaggio C.L Yezerets A. Kung M.C. Kung H.H. Baskaran S. Frye J.G. Smith M.R. Herling D.R. LeBarge W.L. Kupe J. “Mechanistic Studies of the Catalytic Chemistry of NO x in Laboratory Plasma-Catalyst Reactors” SAE 2000-01-2965 2000
- Panov A.G. Tonkyn R.G. Balmer M.L Peden C.H.F. Malkin A. Hoard J.W. “Selective Reduction of NO x in Oxygen Rich Environments with Plasma-Assisted Catalysis: The Role of the Plasma and Reactive Intermediates” SAE 2001-01-3513 2001
- Tonkyn R.G Barlow S.E. Balmer M.L. Orlando T.M. Hoard J. Goulette D. “Vehicle Exhaust Treatment Using Electrical Discharge Methods” SAE 971716 1997
- Hoard J. Laing P. Balmer M.L. Tonkyn R. “Comparison of Plasma-Catalyst and Lean NO x Catalyst for Diesel NO x Reduction” SAE 2000-01-2895 2000
- Penetrante B.M. Brusasco R.M. Merritt B.T. Pitz W.J. Vogtlin G.E. “Feasibility of Plasma Aftertreatment for Simultaneous Control of NO x and Particulates” SAE 1999-01-3637 1999
- Balmer M.L. Tonkyn R. Yoon S. Kolwaite A. Barlow S.E. Maupin G. Hoard J. “NO x Destructive Behavior of Select Materials When Combined with a Non-Thermal Plasma” SAE 1999-01-3640 1999
- Miyadera T. “Selective Reduction of Nitric Oxide with Ethanol Over an Alumina-Supported Silver Catalyst” Appl. Cat. B: Environ. 13 157 165 1997
- Schuchmann X. Laidler X. “Pyrolysis of Acetaldehyde in the Presence of NO” Intl. J. Chem. Kinetics 11 349 380 1970
- 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
- Willi R. Roduit B. Koeppel R.A. Wokaun A. Baiker A. “Selective Reduction of NO by NH 3 Over Vanadia-Based Commercial Catalyst: Parametric Sensitivity and Kinetic Modeling” Chem. Eng. Sci. 51 11 2897 2902 1996
- Siegl W.O. Hammerle R.H. Herrmann H.M. Wenclawiak B.W. Luers-Jongen B. “Organic Emissions Profile for a Light-Duty Diesel Vehicle ” Atmospheric Environment 33 797 805 1999