Journal of Power System Engineering (동력기계공학회지)

The Korean Society for Power System Engineering (한국동력기계공학회)
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NH3 Generation Characteristics of a LNT Catalyst Downstream

LNT 촉매 후단의 NH3 생성 특성

  • Seo, Choong-Kil (Department of Automotive & Mechanical Engineering, Howon University)
  • 서충길 (호원대학교 자동차기계공학과)
  • Received : 2015.03.23
  • Accepted : 2015.12.23
  • Published : 2016.02.28
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Abstract

As diesel engines have high power and good fuel economy on top of less $CO_2$ emissions, their market shares are increasing not only in commercial vehicles but also in passenger cars. LNT, urea-SCR and combination of them have been developed for after-treatment of the exhaust gas to reduce NOx on diesel vehicles. The aim of this study is to investigate the $NH_3$ generation characteristics of LNT catalyst downstream. It was found from the experiments of the LNT catalyst that $H_2$ was useful as a reductant in SCR catalyst because it can enhance the de-NOx performance and improve $NH_3$ selectivity. The $NH_3$ generation of the LNT, when hydrothermally aged at $900^{\circ}C$ for 18 hr, increased to about 90ppm at $300^{\circ}C$ due to Pt sintering and Ba agglomeration. LNT catalyst was most sulfur poisoning at $500^{\circ}C$. The $NH_3$ slip increased due to the reduction of residence time according to SV increase.

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References

  1. C. K. Seo, H. N. Kim, B. C. Choi and M. T. Lim, 2011, "The Optimal Volume of a Combined System of LNT and SCR Catalysts", Journal of Industrial and Engineering Chemistry, Vol. 17, No. 6, pp. 382-385. https://doi.org/10.1016/j.jiec.2010.10.033
  2. C. K. Seo, H. N. Kim and B. C. Choi, 2010, "Characteristics of Adsorption, Desorption of Exhaust Gases and Deactivation of LNT and SCR Catalysts for Diesel Vehicles", Journal of The Korean Society for Power System Engineering, Vol. 14, No. 12, pp. 13-19.
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