This content is not included in your SAE MOBILUS subscription, or you are not logged in.
Development of Three-Way Catalysts Enhanced NOx Purifying Activity
ISSN: 0148-7191, e-ISSN: 2688-3627
Published April 03, 2018 by SAE International in United States
This content contains downloadable datasetsAnnotation ability available
Growing concerns about the depletion of raw materials as vehicle ownership continues to increase is prompting automakers to look for ways of decreasing the use of platinum-group metals (PGMs) in the exhaust systems. This research has developed a new catalyst with strong robustness against fluctuations in the exhaust gas and excellent nitrogen oxide (NOx) conversion performance. One of the key technologies is a new OSC material that has low surface area (SA) and high OSC performance. We enhanced the pyrochlore- ceria/zirconia (CZ) which has a very small SA. In order to enhance the heat resistance and promote the OSC reaction, we selected and optimized the additive element. This material showed high OSC performance especially in the temperature range of 400 degrees or less. Another key technology is washcoat structure that has high gas diffusivity by making connected pore in the washcoat (New pore forming technology). The connected pore means that some pores are connected each other unlike conventional structure which has isolated pores. Compared with the conventional washcoat structure, the new technology has high gas diffusivity. As a result, the developed catalyst showed high NOx purifying activity which enabled nearly 30% reduction of precious metal usage.
CitationChinzei, I., Saito, Y., Morikawa, A., Kato, S. et al., "Development of Three-Way Catalysts Enhanced NOx Purifying Activity," SAE Technical Paper 2018-01-0942, 2018, https://doi.org/10.4271/2018-01-0942.
Data Sets - Support Documents
|[Unnamed Dataset 1]|
- Rohart, E., Larcher, O., Hédouin, C., Allain, M. et al. , “Innovative Materials with High Stability, High OSC, and Low Light-off for Low PGM Technology,” SAE Technical Paper 2004-01-1274 , 2004, doi:10.4271/2004-01-1274.
- Kanazawa, T., Suzuki, J., Takada, T., Suzuki, T. et al. , “Development of Three-Way Catalyst Using Composite Alumina-Ceria-Zirconia,” SAE Technical Paper 2003-01-0811 , 2003, doi:10.4271/2003-01-0811.
- Tanabe, T., Morikawa, A., and Hatanaka, M., “Metal-Support Interaction in Three-Way Catalyst (5)-Sintering Suppression of Rh Supported on Nd Surface Enriched ZrO2 Support,” Shokubai 52(6):465-466, 2010.
- Yoshida, T., Sato, A., Suzuki, H., Tanabe, T. et al. , “Development of High Performance Three-Way-Catalyst,” SAE Technical Paper 2006-01-1061 , 2006, doi:10.4271/2006-01-1061.
- Aoki, Y., Yoshida, T., Tanabe, T., Hatanaka, M. et al. , “Development of Double-Layered Three-Way Catalysts,” SAE Technical Paper 2009-01-1081 , 2009, doi:10.4271/2009-01-1081.
- Fujiwara, T., Takagi, N., Ichinose, H., Yoshioka, M. et al. , “Development of High Performance Three-Way-Catalyst Technology to Lower NOx Emission,” SAE Technical Paper 2009-01-1398 , 2009, doi:10.4271/2009-01-1398.
- Dong, F., Suda, A., Tanabe, T., Nagai, Y. et al. , “Dynamic Oxygen Mobility and a New Insight into the Role of Zr Atoms in Three-Way Catalysts of Pt/CeO2-ZrO2,” Catalysis Today 93-95:827-832, 2004.
- Nagai, Y., Yamamoto, T., Tanaka, T., Yoshida, S. et al. , “X-Ray Absorption Fine Structure Analysis of Local Structure of CeO2-ZrO2 Mixed Oxides with the Same Composition Ratio (Ce/Zr=1),” Catalysis Today 74:225-234, 2002, doi:10.1016/S0920-5861(02)00025-1.
- Kato, S., Yamaguchi, S., Uyama, T., Yamada, H. et al. , “Characterization of Secondary Pores in Washcoat Layers and Their Effect on Effective Gas Transport Properties,” Chemical Engineering Journal 324:370-379, 2017, doi:10.1016/j.cej.2017.05.055.
- Morikawa, A., Yamamura, K., Tanabe, T. et al. , “Development of High Heat-resistant Pyrochlore Type Oxygen Storage Material pCP,” Presentation at the 26th Fall Meeting of the Ceramic Society of Japan, 2014.