bei Google ScholarTitelangaben
Walter, Stefanie ; Ruwisch, Lutz ; Göbel, Ulrich ; Hagen, Gunter ; Moos, Ralf:
Radio-frequency-based determination of the oxygen and the NOx storage level of NOx storage catalysts.
2018
Veranstaltung: CAPOC11 - 11th International Congress on Catalysis and Automotive Pollution Control
, Oct. 29 - 31, 2018
, Brussels, Belgium.
(Veranstaltungsbeitrag: Kongress/Konferenz/Symposium/Tagung
,
Poster
)
Abstract
In recent years, research on microwave-based catalyst state diagnosis for diesel engines has focused mainly on SCR systems. To increase the efficiency of exhaust aftertreatment systems, SCR catalysts can be combined with NOx storage catalysts (NSC). For optimum performance, the degree of loading of the storage components has to be monitored. Up to now, in commercial application this has been done indirectly by using mathematical models. In this paper the opportunities of a simple radio frequency (RF) based method for a direct determination are highlighted. Therefore, a commercial NSC was investigated between 210 and 390 °C. A linear dependence between the RF signals and the stored amount of NO was found. Furthermore, the RF parameters are not directly affect by the NO or oxygen concentration, but only indirectly by amount of stored NO, which depends on the NO concentration. By evaluating multiple signals, which are based on different material effects, a separate determination of the oxygen and NOx storage level could be realized.