1. Home
  2. Honda R&D Technical Review Vol.25 N...
  3. Elucidation of Deterioration Mechan...

Technical Review e-Book: Summary

Elucidation of Deterioration Mechanism and Improvement of Durability for Lean NOx Catalyst

Article of Honda R&D Technical Review Vol.25 No.1

Summary

The exhaust gas temperatures of diesel engines have been falling gradually due to engine efficiency improvement and body weight reduction. Thus, an NOx aftertreatment system that has high NOx conversion at lower temperature is required for these engines. To meet demand, the development of a new Lean NOx Catalyst with a new De-NOx mechanism has been carried out. However, it has recently been found that Lean NOx Catalyst has a durability issue during aging in an actual exhaust gas environment. The deterioration mechanism of Lean NOx Catalyst was clarified and durability enhancement of the material was conducted. As a result of an analysis using a combination of surface analysis and ab-initio calculation, it was found that the sulfur in exhaust gas was irreversibly adsorbed onto platinum in the form of sulfate, which reduced catalyst activity. A new Lean NOx Catalyst that has high durability even after aging with exhaust gas was developed by improving NO2 adsorption activity and NO2 reduction activity, which had been degraded by sulfur poisoning.

Reference

(1) Guo, G., Dobson, D., Warner, J., Ruona, W., et al.: Advanced Urea SCR System Study with a Light Duty Diesel Vehicle, SAE Technical Paper 2012-01-0371 (2012)
(2) Moon, S., Choi, B., Lee, H., Hyun, G., et al.: Development of DPF/SCR System for Heavy Duty Diesel Engine, SAE Technical Paper, 2012-01-0369 (2012)
(3) Adouane, D., Dutilleul, H., Guibert, P., Teixeira, M., et al.: Impact of Thermal and Engine Ageing on a Fully Formulated Lean NOx Trap, SAE Technical Paper, 2012-01-1746 (2012)
(4) Kim, K., Cho, S.: The Emission Development for Lean NOx Trap System to Meet Tier2Bin5, SAE Technical Paper, 2010-01-0566 (2010)
(5) Chen, X., Schwank, J.: Investigation on NOx Storage Characteristics and Aging Influence of Lean NOx Trap Model Catalyst BaO-Pt/Al2O3, SAE Technical Paper, 2010-01-0364 (2010)
(6) Kouakou, A., Fresnet, F., Granger, P., and Dainhaut, F.: New Insight in Ammonia Formation During the Purge of a Lean NOx Trap in Vehicles Running Conditions, SAE Technical Paper, 2009-01-2710 (2009)
(7) AL-Harbi, M., Epling, W., Yezerets, A., Currier, N., et al.: The Effects of Thermal Degradation on the Performance of a NOx Storage/Reduction Catalyst, SAE Technical Paper, 2009-01-0631 (2009)
(8) Morita, T., Suzuki, N., Satoh, N., Wada, K., Ohno, H.: Study on Low NOx Emission Control Using Newly Developed Lean NOx Catalyst for Diesel Engines, SAE Technical Paper 2007-01-0239 (2007)
(9) Delley, B.: An All-Electron Numerical Method for Solving the Local Density Functional for Polyatomic Molecules, J. Chem. Phys., 92, 508 (1990)
(10) Delley, B.: From molecules to solids with the DMol3 approach, J. Chem. Phys., 113, 7756 (2000)
(11) Vosko, S. H., Wilk, L., Nusair, M.: Accurate spin-dependent electron liquid correlation energies for local spin density calculations: a critical analysis, Can. J. Phys., 58, 1200 (1980)

Author (organization or company)

Yuichi MATSUO(Automobile R&D Center)、Shinya ISHIMARU(Automobile R&D Center)、Masanori HASHIMOTO(Automobile R&D Center)、Tetsuo ENDO(Automobile R&D Center)、Yoshiaki MATSUZONO(Automobile R&D Center)、Makoto NAGATA(N. E. CHEMCAT CORPORATION)

We would like to get your opinion on this research paper. (This is only applicable to registered members.)

The readers of this research paper have also selected these research papers.

Elucidation of Hydrocarbon Purification Mechanism of Catalyst for Lean Burn Engine Using Surface Analysis and Ab-initio Calculation with Large-scale Cluster Model
Article of Honda R&D Technical Review Vol.31 No.1
Detailed Structural Analysis of Pd Particles through Use of XAFS and STEM-EELS in Tandem
Article of Honda R&D Technical Review Vol.29 No.1
Development of New 1.6 L 2-stage Turbocharged Diesel Engine for Honda CR-V
Article of Honda R&D Technical Review Vol.27 No.2