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Topics in Catalysis

, Volume 59, Issue 10–12, pp 1054–1058 | Cite as

Hysteresis Phenomena on Pt- and Pd-Diesel Oxidation Catalysts: Experimental Observations

  • H. DubbeEmail author
  • G. Eigenberger
  • U. Nieken
Original Paper

Abstract

In Diesel Oxidation Catalysts (DOC) platinum (Pt), palladium (Pd), or a combination of both (alloyed or multilayered) are the typical active components. During lightoff/lightout experiments, hysteresis phenomena of CO, NO, and HC conversion have repeatedly been reported and attributed to thermal effects, to surface coverage effects and/or to noble metal oxidation. A detailed understanding of the causes of these hysteresis phenomena will be crucial, especially for modeling purposes. The present contribution provides detailed experimental evidence on single component conversion as well as on the mutual influence of CO, NO, and HC on the respective conversion for close to commercial Pt- and Pd-only catalysts under isothermal conditions. It will be shown, that hysteresis effects on Pd-only catalysts mostly vanish after one lightoff. Contrarily, on Pt-only catalysts, a cyclic, stationary conversion hysteresis during lightoff/lightout experiments is observed for CO and NO. C3H6-only however does not show this phenomenon whereas small hysteresis in conversion can be observed in combination with CO and/or NO.

Keywords

NO oxidation Hysteresis Deactivation Reactivation Platinum Palladium 

Notes

Acknowledgments

Financial support by the FVV e.V. is gratefully acknowledged.

References

  1. 1.
    Gänzler AM, Casapu M, Boubnov A, Müller O, Conrad S, Lichtenberg H, Frahm R, Grunwaldt J-D (2015) J Catal 328:216–224CrossRefGoogle Scholar
  2. 2.
    Hauptmann W (2009) Ph.D. thesis, University of DarmstadtGoogle Scholar
  3. 3.
    Salomons S, Hayes RE, Votsmeier M, Drochner A, Vogel H, Malmberg S, Gieshoff J (2007) Appl Catal B 70:305–313CrossRefGoogle Scholar
  4. 4.
    Hauff K (2013) Ph.D. thesis, University of StuttgartGoogle Scholar
  5. 5.
    Eiswirth RM, Krischer K, Ertl G (1990) J Appl Phys A—Solids Surf 51:79–90CrossRefGoogle Scholar
  6. 6.
    Zorn K, Giorgio S, Halwax E, Henry CR, Grönbeck H, Rupprechter G (2011) J Phys Chem C 115:1103–1111CrossRefGoogle Scholar
  7. 7.
    Hauff K, Dubbe H, Tuttlies U, Eigenberger G, Nieken U (2013) Appl Catal B Env (Elsevier) 129:273–281CrossRefGoogle Scholar
  8. 8.
    Abedi A, Hayes R, Votsmeier M, Epling WS (2012) Catal Lett 142:930–935CrossRefGoogle Scholar
  9. 9.
    Levitsky AA, Polyak SS, Shtern VY (1984) Int J Chem Kinet 16:1275–1285CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  1. 1.Institute of Chemical Process EngineeringUniversity of StuttgartStuttgartGermany

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