Skip to main content
SpringerLink
Log in

NO x uptake mechanism on Pt/BaO/Al2O3 catalysts

  • Published:
Catalysis Letters Aims and scope Submit manuscript

The NO x adsorption mechanism on Pt/BaO/Al2O3 catalysts was investigated by performing NO x storage/reduction cycles, NO2 adsorption and NO + O2 adsorption on 2%Pt/(x)BaO/Al2O3 (x = 2, 8, and 20 wt%) catalysts. NO x uptake profiles on 2%\Pt/20%BaO/Al2O3 at 523 K show complete uptake behavior for almost 5 min, and then the NO x level starts gradually increasing with time and it reaches 75% of the inlet NO x concentration after 30 min time-on-stream. Although this catalyst shows fairly high NO x conversion at 523 K, only ~2.4 wt% out of 20 wt% BaO is converted to Ba(NO3)2. Adsorption studies by using NO2 and NO + O2 suggest two different NO x adsorption mechanisms. The NO2 uptake profile on 2%Pt/20%BaO/Al2O3 shows the absence of a complete NO x uptake period at the beginning of adsorption and the overall NO x uptake is controlled by the gas–solid equilibrium between NO2 and BaO/Ba(NO3)2 phase. When we use NO + O2, complete initial NO x uptake occurs and the time it takes to convert ~4% of BaO to Ba(NO3)2 is independent of the NO concentration. These NO x uptake characteristics suggest that the NO + O2 reaction on the surface of Pt particles produces NO2 that is subsequently transferred to the neighboring BaO phase by spill over. At the beginning of the NO x uptake, this spill-over process is very fast and so it is able to provide complete NO x storage. However, the NO x uptake by this mechanism slows down as BaO in the vicinity of Pt particles are converted to Ba(NO3)2. The formation of Ba(NO3)2 around the Pt particles results in the development of a diffusion barrier for NO2, and increases the probability of NO2 desorption and consequently, the beginning of NO x slip. As NO x uptake by NO2 spill-over mechanism slows down due to the diffusion barrier formation, the rate and extent of NO2 uptake are determined by the diffusion rate of nitrate ions into the BaO bulk, which, in turn, is determined by the gas phase NO2 concentration.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  1. S. Yoon A.G. Panov R.G. Tonkyn A.C. Ebeling S.E. Barlow M.L. Balmer (2002) Catal. Today 72 243 Occurrence Handle1:CAS:528:DC%2BD38Xis1ClsL8%3D Occurrence Handle10.1016/S0920-5861(01)00499-0

    Article  CAS  Google Scholar 

  2. P.L.T. Gabrielson (2004) Top. Catal. 28 177 Occurrence Handle10.1023/B:TOCA.0000024348.34477.4c

    Article  Google Scholar 

  3. M. Takeuchi S. Matsumoto (2004) Top. Catal. 28 151 Occurrence Handle1:CAS:528:DC%2BD2cXjt1SgtLg%3D Occurrence Handle10.1023/B:TOCA.0000024344.91688.e4

    Article  CAS  Google Scholar 

  4. N. Takahashi H. Shinjoh T. Iijima T. Suzuki K. Yamazaki K. Yokota H. Suzuki N. Miyoshi S. Matsumoto T. Tanizawa T. Tanaka S. Tateishi K. Kasahara (1996) Catal. Today 27 63 Occurrence Handle1:CAS:528:DyaK28XhtF2hs7Y%3D Occurrence Handle10.1016/0920-5861(95)00173-5

    Article  CAS  Google Scholar 

  5. W.S. Epling L.E. Campbell A. Yezerets N.W. Currier J.E. Parks (2004) Catal. Rev. Sci. Eng. 46 163 Occurrence Handle10.1081/CR-200031932

    Article  Google Scholar 

  6. W.S. Epling J.E. Parks G.C. Campbell A. Yezerets N.W. Currier L.E. Campbell (2004) Catal. Today 96 21 Occurrence Handle1:CAS:528:DC%2BD2cXns12isrY%3D Occurrence Handle10.1016/j.cattod.2004.05.004

    Article  CAS  Google Scholar 

  7. L. Olsson E. Fridell (2002) J. Catal. 210 340 Occurrence Handle1:CAS:528:DC%2BD38XmsFWnurY%3D Occurrence Handle10.1006/jcat.2002.3698

    Article  CAS  Google Scholar 

  8. F. Prinetto G. Ghiotti I. Nova L. Lietti E. Tronconi P. Forzatti (2001) J. Phys. Chem. B 105 12732 Occurrence Handle1:CAS:528:DC%2BD3MXoslSnt7k%3D Occurrence Handle10.1021/jp012702w

    Article  CAS  Google Scholar 

  9. J. Dawody M. Skoglundh S. Wall E. Fridell (2005) J. Mol. Catal. A 225 259 Occurrence Handle1:CAS:528:DC%2BD2cXhtVKrsbnO Occurrence Handle10.1016/j.molcata.2004.09.011

    Article  CAS  Google Scholar 

  10. L. Olsson E. Fridell M. Skoglundh B. Andersson (2002) Catal. Today 73 263 Occurrence Handle1:CAS:528:DC%2BD38XktVejsrw%3D Occurrence Handle10.1016/S0920-5861(02)00009-3

    Article  CAS  Google Scholar 

  11. L. Olsson R.J. Blint E. Fridell (2005) Ind. Eng. Chem. Res. 44 3021 Occurrence Handle1:CAS:528:DC%2BD2MXitlSjtrk%3D Occurrence Handle10.1021/ie0494059

    Article  CAS  Google Scholar 

  12. I. Nova L. Castoldi L. Lietti E. Tronconi P. Forzatti F. Prinetto G. Ghiotti (2004) J. Catal. 222 377 Occurrence Handle1:CAS:528:DC%2BD2cXhvV2gsLk%3D Occurrence Handle10.1016/j.jcat.2003.11.013

    Article  CAS  Google Scholar 

  13. F. Prinetto G. Ghiotti I. Nova L. Castoldi L. Lietti E. Tronconi P. Forzatti (2003) Phys. Chem. Chem. Phys. 5 4428 Occurrence Handle1:CAS:528:DC%2BD3sXnsl2ksLs%3D Occurrence Handle10.1039/b305815h

    Article  CAS  Google Scholar 

  14. W.S. Epling G.C. Campbell J.E. Parks (2003) Catal. Lett. 90 45 Occurrence Handle1:CAS:528:DC%2BD3sXnsFShu7g%3D Occurrence Handle10.1023/A:1025864109922

    Article  CAS  Google Scholar 

  15. J. Despres M. Koebel O. Korcher M. Elsener A. Wokaun (2003) Appl. Catal. B 43 389 Occurrence Handle1:CAS:528:DC%2BD3sXkvF2gsr4%3D Occurrence Handle10.1016/S0926-3373(03)00004-3

    Article  CAS  Google Scholar 

  16. J. Szanyi J.H. Kwak J. Hanson C. Wang T. Szailer C.H.F. Peden (2005) J. Phys. Chem. B 109 7339 Occurrence Handle1:CAS:528:DC%2BD2MXit12ju7Y%3D Occurrence Handle10.1021/jp044160z

    Article  CAS  Google Scholar 

  17. J. Szanyi J.H. Kwak D.H. Kim S.D. Burton C.H.F. Peden (2005) J. Phys. Chem. B 109 27 Occurrence Handle1:CAS:528:DC%2BD2cXhtVKitL7P Occurrence Handle10.1021/jp044993p

    Article  CAS  Google Scholar 

  18. L. Castoldi I. Nova L. Lietti P. Forzatti (2004) Catal. Today 96 263 Occurrence Handle10.1016/j.cattod.2004.05.006

    Article  Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Institute for Interfacial Catalysis, Pacific Northwest National Laboratory, Richland, WA, 99352, USA

    Ja Hun Kwak, Do Heui Kim, Tamás Szailer, Charles H. F. Peden & János Szanyi

Authors
  1. Ja Hun Kwak
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Do Heui Kim
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Tamás Szailer
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Charles H. F. Peden
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. János Szanyi
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Do Heui Kim.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Kwak, J.H., Kim, D.H., Szailer, T. et al. NO x uptake mechanism on Pt/BaO/Al2O3 catalysts. Catal Lett 111, 119–126 (2006). https://doi.org/10.1007/s10562-006-0153-4

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10562-006-0153-4

Keywords

Search

Navigation