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http://dx.doi.org/10.9726/kspse.2016.20.1.018

NH3 Generation Characteristics of a LNT Catalyst Downstream  

Seo, Choong-Kil (Department of Automotive & Mechanical Engineering, Howon University)
Publication Information
Journal of Power System Engineering / v.20, no.1, 2016 , pp. 18-23 More about this Journal
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.
Keywords
Diesel engine; Catalyst; Lean NOx Trap; Selective Catalytic Reduction; $NH_3$;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
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