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NOx Reduction with the HC-SCR System over Cu/Zeolite Based Catalysts
Technical Paper
2015-01-2012
ISSN: 0148-7191, e-ISSN: 2688-3627
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English
Abstract
Diesel engine is one the effective solutions for reducing CO2 and recognized as a leading candidate for mitigating global warming. To comply with increasingly stringent emission standards, all diesel engines require some sort of NOx control systems such as selective catalytic reduction (SCR) systems. The SCR catalyst for reducing NOx from diesel engines is classified into two groups, urea-SCR and HC-SCR catalyst, respectively. Although the urea-SCR catalyst is widely recognized as promising de-NOx technology in respect to the NOx conversion efficiency, it have some outstanding issues such as ammonia slip, urea injection, storage space, freezing and some infrastructures for supplying urea water solutions. In an attempt to overcome the inherent shortcoming of existing urea-SCR catalyst, hydrocarbons have been considered as alternative reducing agents for SCR process, instead of NH3. SCR of NOx with hydrocarbons (HC-SCR) is an attractive way for NOx abatement under lean burn conditions, i.e. in an oxygen rich atmosphere, especially when the diesel exhaust is used as reducing agents. In this system, high NOx conversion efficiency is required over wide temperature range and exhaust flow rate. This study focuses on the HC-SCR system to evaluate the de-NOx performance with a newly developed catalytic reactor in steady and transient conditions, respectively. The performance of HC-SCR catalysts, Cu/ZSM-5 and Cu/β-zeolite prepared by Cu ion-exchange of the parent zeolites, was contrasted and compared under a variety of operating conditions using a laboratory scale test bench. The catalytic reactor has an advantage of evaluating the NOx conversion for all after-treatment devices at both steady and transient conditions. In this study 4 kinds of Cu/zeolite catalysts with a volume of 8 cc were evaluated with the synthetic gas supply module and 25,000 and 50,000 h−1 of GHSV (Gas Hourly Space Velocity). The reducing agent, n-C4H10, was injected from a gas injector equipped upstream of a catalytic reactor.
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Citation
Lee, K., Ogita, Y., Sato, S., and Kosaka, H., "NOx Reduction with the HC-SCR System over Cu/Zeolite Based Catalysts," SAE Technical Paper 2015-01-2012, 2015, https://doi.org/10.4271/2015-01-2012.Also In
References
- Knafl A. , Han M. , Bohac SV. , Assanis DN. , Szymkowicz PG. Comparison of Diesel Oxidation Catalyst Performance on an Engine and a Gas Flow Reactor SAE Technical Paper 2007-01-0231 2007
- Choi B. C. and Lee K. S. LNT/CDPF catalysts for simultaneous removal of NOx and PM from diesel vehicle exhaust Chemical Engineering Journal 240 476 486 2014
- Cavataio G. , Girard JW. and Lambert CK. Cu/Zeolite SCR on High Porosity Filters: Laboratory and Engine Performance Evaluations SAE Technical Paper 2009-01-0897 2009
- Morcos M. , Ayyappan P. and Harris T. Characterization of DPF Ash for Development of DPF Regeneration Control and Ash Cleaning Requirements SAE Technical Paper 2011-01-1248 2011
- Iwamoto M. , Yahiro H. and Tanda K. Catalytic Decomposition of Nitrogen Monoxide over Copper Ion-Exchanged Zeolites. Influence of Zeolite Structure and Aluminum Content on the Catalytic Activity Studies in Surface Science and Catalysis 44 219 226 1989
- Hamada H. , Kintaichi Y. , Sasaki M. , Ito T. and Tabata M. Selective reduction of nitrogen monoxide with propane over alumina and HZSM-5 zeolite: Effect of oxygen and nitrogen dioxide intermediate Applied Catalysis 70 L15 L20 1991
- Held W. , König A. , Richter T. , and Puppe L. Catalytic NOx Reduction in Net Oxidizing Exhaust Gas SAE Technical Paper 900496 1990
- Małgorzata A.-T. , Andrzej K. , Patrick D. C. and Gérald D.-M. SCR NOx mechanistic study with a mixture of hydrocarbons representative of the exhaust gas from coal combustion over Rh/Ce 0.62 Zr 0.38 O 2 catalyst Fuel 150 21 28 2015
- Li L. and Guan N. HC-SCR reaction pathways on ion exchange ZSM-5 catalysts Microporous and Mesoporous Materials 117 450 457 2009
- Long Z. M. , Li J. H. and Woo S. I. Recent advances in the selective catalytic reduction of NOx by hydrogen in the presence of oxygen Energy & Environmental Science 10 8799 8814 2012
- Cheng X. , Bi X. T. Reaction kinetics of selective catalytic reduction of NOx by propylene over Fe/ZSM-5 Chemical Engineering Journal 211 212 453 462 2012
- He H. , Zhang X. , Wu Q. , Zhang C. and Yu Y. Review of Ag/Al 2 O 3 -Reductant System in the Selective Catalytic Reduction of NOx Catalysis Surveys from Asia 12 38 55 2008
- Liu X. , and Woo S. I. Recent Advances in Catalytic DeNOx Science and Technology Catalysis Reviews: Science and Engineering 48 43 89 2006
- Houel V. , James D. , Millington P. , Pollington S. , Poulston S. , Rajaram R. and Torbati R. A comparison of the activity and deactivation of Ag/Al 2 O 3 and Cu/ZSM-5 for HC-SCR under simulated diesel exhaust emission conditions Journal of Catalysis 230 150 157 2005
- Kim P. S. , Kim M. K. , Cho B. K. , Nam I. S. , Oh S. H. Effect of H 2 on deNOx performance of HC-SCR over Ag/Al 2 O 3 : Morphological, chemical, and kinetic changes Journal of Catalysis 301 65 76 2013
- Sato S. , Ogita Y. , Lee K. S. and Kosaka H. A study on the improvement of NOx conversion efficiency of HC-SCR system The 25th Internal Combustion Engine Symposium, JSAE Paper 20143877 66 1 9 2014