This content is not included in your SAE MOBILUS subscription, or you are not logged in.
The NH 3 -SCR Reaction Performance with Fe/Zeolite Based Catalytic Honeycomb Substrate
ISSN: 0148-7191, e-ISSN: 2688-3627
Published April 20, 2009 by SAE International in United States
Annotation ability available
Stringent NOx emission legislation accelerates the study of NOx aftertreatment. Urea-SCR system which is one of promising NOx reduction measures has been widely studied and been put to practical use not only for heavy duty vehicles but also passenger cars. As SCR catalyst, although use of zeolite ion-exchanged with transition metals (M/zeolite) has been under intense investigation, in particular, NOx conversion performance at low temperatures are still a challenging problem. Increasing the number of active sites is one of countermeasures to solve the problem.
In this study, a catalytic honeycomb substrate mainly comprised of M/zeolite (NCH structure) and a conventional wash coated type catalyst(conventional structure) were prepared, respectively. To clarify the advantage of NCH structure, a relationship between NH3 adsorption and NOx conversion of the NCH structure and of the conventional structure were evaluated in both synthetic gas bench and engine bench. As a result, it was found that NCH structure has possibility to increase controllability of NH3 breakthrough due to its higher NH3 adsorptive capability and that NOx conversion performance of the NCH structure is always superior to the conventional structure at a given NH3 adsorption ratio. Especially at low temperatures, the NCH structure exhibits approximately 1.6 times NOx conversion performance of the conventional structure.
CitationIdo, T., Kunieda, M., Miwa, Y., Yoshimura, K. et al., "The NH3-SCR Reaction Performance with Fe/Zeolite Based Catalytic Honeycomb Substrate," SAE Technical Paper 2009-01-0906, 2009, https://doi.org/10.4271/2009-01-0906.
- Heck R. M. et al. “Catalytic abatement of nitrogen oxides–stationary applications” Catal. Today 53 519 523 1999
- Forzatti P. et al. “Environmental catalysis for stationary applications” Catal. Today 62 51 65 2000
- Fritz N. et al. “On-Road Demonstration of NOx emission Control for Heavy Duty Diesel Trucks with SINOx Urea SCR System” SAE Paper 1999-01-0111 1999
- Hirata K. et al. “Development of Urea-SCR System for Heavy-Duty Commercial Vehicles” SAE Paper 2005-01-1860 2005
- Helden R. v. et al. ” Optimization of urea SCR deNOx System for HD Diesel Engines” SAE Paper 2004-01-0154 2004
- Ido T. et al. “Fundamental Study of Newly Developed Flow Through Catalytic Honeycomb for Improving NOx Emission” MinNOx2008 presentation 2008
- Cavataio G. et al. “Laboratory Testing of Urea-SCR Formulations to Meet Tir 2 Bin 5 Emissions” SAE 2007-01-1575
- Sano T. et al. “Influence of Crystallinity of HZSM-5 Zeolite on Its Dealumination Rate” Zeolites 19 80 86 1997
- Savara A. et al. “Catalytic reduction of NH4NO3 by NO: Effects of solid acids and implications for low temperature DeNOx processes” Appl. Catal. B 81 251 257 2008
- Koebel M. et al. “Urea-SCR: a promising technique to reduce NOx emissions from automotive diesel engine” Catal. Today 59 335 345 2000
- Kleemann M. et al. “Hydrolysis of Isocyanic Acid on SCR Catalyst” Ind. Eng. Chem. Res. 39 4120 4126 2000
- Piazzesi G. et al. “Isocyanic acid hydrolysis over Fe-ZSM5 in urea-SCR” Catal. Commun. 7 600 603 2006