Skip to main content
SpringerLink
Log in

Transient Redox Behavior of a NH3-SCR Cu-CHA SCR Catalyst: Effect of O2 Feed Content Variation

  • Original Paper
  • Published:
Topics in Catalysis Aims and scope Submit manuscript

Abstract

Notwithstanding the high efficiency of the modern NH3-SCR technology in reducing NOx from Diesel engines exhausts, their removal is still a concern in view of the forthcoming application of more stringent environmental guidelines. Actually, a large fraction of the total NOx emitted by the engine derives from transient engine operations, especially at low temperature. In this context, herein we systematically investigate the effect of oxygen feed content variation under Standard SCR reaction conditions over a reference Cu-CHA catalyst. Transient Response Methods (TRM) have been applied to mimic lean to rich and rich to lean transients. Steady state experiments reveal that the higher the O2 feed content, the higher the NOx conversion and N2O formation, with N2O turning out to be very sensitive to oxygen concentration changes. Additionally, through TRM runs, it is possible to obtain quantitative information on the average fraction of oxidized Cu sites (CuII/Cutot) at the Standard SCR steady state. Particularly, the NOx conversion and the CuII fraction increase both with temperature and with O2 feed content. Hence, the higher the oxidized copper fraction, the higher the N2O formation in the Standard SCR reaction.

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

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8

Similar content being viewed by others

Data Availability

Not applicable.

Code Availability

Not applicable.

References

  1. Seykens X, Kupper F, Mentink P, Ramesh S (2018) Towards ultra-low NOx emissions within GHG phase 2 constraints: main challenges and technology directions. SAE Technical Paper 2018-01-0331. https://doi.org/10.4271/2018-01-0331

  2. Nova I, Tronconi E (2014) Urea-SCR technology for deNOx aftertreatment of diesel exhausts. Springer-Verlag, New York

    Book  Google Scholar 

  3. Selleri T, Melas AD, Joshi A, Manara D, Perujo A, Suarez-Bertoa R (2021) An overview of lean exhaust deNOx aftertreatment technologies and NOx emission regulations in the european union. Catalysts 11:404

    Article  CAS  Google Scholar 

  4. Brandenberger S, Kröcher O, Tissler A, Althoff R (2008) The state of the art in selective catalytic reduction of NOx by ammonia using metal-exchanged zeolite catalysts. Catal Rev: Sci Eng 50:492–531

    Article  CAS  Google Scholar 

  5. Gramigni F, Iacobone U, Nasello ND, Selleri T, Usberi N, Nova I (2021) Review of hydrocarbon poisoning and deactivation effects on Cu-zeolite, Fe-zeolite, and vanadium-based selective catalytic reduction catalysts for NOx removal from lean exhausts. Ind Eng Chem Res 60:6403–6420

    Article  CAS  Google Scholar 

  6. Beale AM, Gao F, Lezcano-Gonzalez I, Peden CHF, Szanyi J (2015) Recent advances in automotive catalysis for NOx emission control by small-pore microporous materials. Chem Soc Rev 44:7371–7405

    Article  CAS  PubMed  Google Scholar 

  7. Gao F, Peden CHF (2018) Recent progress in atomic-level understanding of Cu/SSZ-13 selective catalytic reduction catalysts. Catalysts 8:140–163

    Article  Google Scholar 

  8. Borfecchia E, Beato P, Svelle S, Olsbye U, Lamberti C, Bordiga S (2018) Cu-CHA—a model system for applied selective redox catalysis. Chem Soc Rev 47:8097–8133

    Article  CAS  PubMed  Google Scholar 

  9. Paolucci C, Di Iorio JR, Schneider WF, Gounder R (2020) Solvation and mobilization of copper active sites in zeolites by ammonia: consequences for the catalytic reduction of nitrogen cxides. Acc Chem Res 53:1881–1892

    Article  CAS  PubMed  Google Scholar 

  10. Liu C, Kubota H, Amada T, Kenichi K, Takashi T, Zen M, Kakuya U, Junya O, Atsushi S, Takuya T, Nao T, Tsuneji S, Ken-ichi S (2020) In situ spectroscopic studies on the redox cycle of NH3–SCR over Cu-CHA zeolites. ChemCatChem 12:3050–3059

    Article  CAS  Google Scholar 

  11. Hu W, Selleri T, Gramigni F, Fenes E, Rout KR, Liu S, Nova I, Chen D, Gao X, Tronconi E (2021) On the redox mechanism of low-temperature NH3-SCR over Cu-CHA: a combined experimental and theoretical study of the eeduction half cycle. Angew Chemie 133:7273–7280

    Article  Google Scholar 

  12. Chen L, Janssens TVW, Vennestrøm PNR, Jansson J, Skoglundh M, Gröbeck H (2020) A complete multi-site reaction mechanism for low-temperature NH3-SCR over Cu-CHA. ACS Catal 10:5646–5656

    Article  CAS  Google Scholar 

  13. Hu W, Gramigni F, Nasello ND, Usberti N, Iacobone U, Liu S, Nova I, Gao X, Tronconi E (2022) Dynamic binuclear CuII sites in the reduction half-cycle of low-temperature NH3-SCR over Cu-CHA catalysts. ACS Catal 12(9):5263–5274

    Article  CAS  Google Scholar 

  14. Gramigni F, Nasello ND, Usberti N, Iacobone U, Selleri T, Hu W, Liu S, Gao X, Nova I, Tronconi E (2021) Transient kinetic analysis of low-temperature NH3-SCR over Cu-CHA catalysts reveals a quadratic dependence of Cu reduction rates on CuII. ACS Catal 11:4821–4831

    Article  CAS  Google Scholar 

  15. Gao F, Szanyi J (2018) On the hydrothermal stability of Cu/SSZ-13 SCR catalysts. Appl Catal A Gen 560:185–194

    Article  CAS  Google Scholar 

  16. Luo J, Gao F, Kamasamudram K, Currier N, Peden CHF, Yezerets A (2017) New insights into Cu/SSZ-13 SCR catalyst acidity. Part I: nature of acidic sites probed by NH3 titration. J Catal 348:291–299

    Article  CAS  Google Scholar 

  17. Paolucci C, Parekh AA, Khurana I, Di Iorio JR, Li H, Caballero JDA, Shih AJ, Anggara T, Delgass WN, Miller JT, Ribeiro FH, Gounder R, Schneider W (2016) Catalysis in a cage: condition-dependent speciation and dynamics of exchanged cu cations in SSZ-13 zeolites. J Am Chem Soc 138:6028–6048

    Article  CAS  PubMed  Google Scholar 

  18. Villamaina R, Liu S, Nova I, Tronconi E, Ruggeri MP, Collier J, York A, Thompsett D (2019) Speciation of Cu cations in Cu-CHA catalysts for NH3-SCR: Effects of SiO2/AlO3 ratio and Cu-loading investigated by transient response methods. ACS Catal 9:8916–8927

    Article  CAS  Google Scholar 

  19. Chen S, Yanakiev O (2005) Transient NOx emission reduction using exhaust oxygen concentration based control for a diesel engine. SAE Technical Paper 2005-01-0372. https://doi.org/10.4271/2005-01-0372

  20. Liu B, Yao D, Wu F, Wei L, Li X, Wang X (2019) Experimental investigation on N2O formation during the selective catalytic reduction of NOx with NH3 over Cu-SSZ-13. Ind Eng Chem Res 58:20516–20527

    Article  CAS  Google Scholar 

  21. Zhang D, Yang RT (2018) N2O formation pathways over zeolite-supported Cu and Fe catalysts in NH3-SCR. Energy Fuels 32:2170–2182

    Article  CAS  Google Scholar 

  22. Ahari H, Smith M, Zammit M, Price K, Jacques J, Pauly T, Wang L (2015) Impact of SCR integration on N2O emissions in diesel application. SAE Int J Passeng Cars-Mech Syst 8:526–530

    Article  Google Scholar 

  23. Deka DJ, Daya R, Ladshaw A, Joshi S, Partridge WP (2021) A transient-response methodology based on experiments and modeling for Cu-redox half-cycle kinetic analysis on a Cu-SSZ-13 SCR catalyst. Chem Eng J 435:134219

    Article  Google Scholar 

  24. Daya R, Trandal D, Menon U, Deka DJ, Partridge WP, Joshi S (2022) Kinetic model for the reduction of CuII sites by NO+NH3 and reoxidation of NH3-solvated CuI sites by O2 and NO in Cu-SSZ-13. ACS Catal 12:6418–6433

    Article  CAS  Google Scholar 

  25. Grossale A, Nova I, Tronconi E (2009) Ammonia blocking of the “Fast SCR” reactivity over a commercial Fe-zeolite catalyst for diesel exhaust aftertreatment. J Catal 265:141–147

    Article  CAS  Google Scholar 

  26. Colombo M, Nova I, Tronconi E (2010) A comparative study of the NH3-SCR reactions over a Cu-zeolite and a Fe-zeolite catalyst. Catal Today 151:223–230

    Article  CAS  Google Scholar 

  27. Usberti N, Gramigni F, Nasello ND, Iacobone U, Selleri T, Hu W, Liu S, Gao X, Nova I, Tronconi E (2020) An experimental and modelling study of the reactivity of adsorbed NH3 in the low temperature NH3-SCR reduction half-cycle over a Cu-CHA catalyst. Appl Catal B Environ 279:119397

    Article  CAS  Google Scholar 

  28. Kwak JH, Tonkyn RG, Kim DH, Szanyi J, Peden CHF (2010) Excellent activity and selectivity of Cu-SSZ-13 in the selective catalytic reduction of NOx with NH3. J Catal 275:187–190

    Article  CAS  Google Scholar 

  29. Akter N, Han L, Huaman D, Kang Y, Kim T (2016) NO and NH3 Oxidation over zeolite materials. Mater Today Proc 3:550–555

    Article  Google Scholar 

  30. Hünnekes EV, Van Der Heijden PVAM, Patchett JA (2006) Ammonia oxidation catalysts for mobile SCR systems. SAE Tech Pap 115:237–243

    Google Scholar 

  31. Koebel M, Elsener M, Kleemann M (2000) Urea-SCR: a promising technique to reduce NOx emissions from automotive diesel engines. Catal Today 59:335–345

    Article  CAS  Google Scholar 

  32. Feng Y, Janssens TVW, Vennestrøm PNR, Jansson J, Skoglundh M, Gröbeck H (2021) The role of H+- And Cu+-sites for N2O formation during NH3-SCR over Cu-CHA. J Phys Chem C 125:4595–4601

    Article  CAS  Google Scholar 

  33. Xi Y, Ottinger NA, Keturakis CJ, Liu ZG (2021) Dynamics of low temperature N2O formation under SCR reaction conditions over a Cu-SSZ-13 catalyst. Appl Catal B Environ 294:120245

    Article  CAS  Google Scholar 

  34. Olsson L, Wijayanti K, Leistner K, Kumar A, Joshi SY, Kamasamudram K, Currier NW, Yezerets A (2015) A multi-site kinetic model for NH3-SCR over Cu/SSZ-13. Appl Catal B Environ 174–175:212–224

    Article  Google Scholar 

  35. Hui S, Yao Q, Wang D, Niu Y (2019) Effect of oxygen on N2O and NO formation from NH3 oxidation over MnOx/TiO2 catalysts. Energy Procedia 158:1497–1501

    Article  CAS  Google Scholar 

  36. Partridge WP, Joshi SY, Pihl JA, Currier NW (2018) New operando method for quantifying the relative half-cycle rates of the NO SCR redox cycle over Cu-exchanged zeolites. Appl Catal B Environ 236:195–204

    Article  CAS  Google Scholar 

  37. Hu W, Iacobone U, Gramigni F, Zhang Y, Wang X, Liu S, Zheng C, Nova I, Gao X, Tronconi E (2021) Unraveling the hydrolysis of Z2Cu2+ to ZCu2+(OH)- and its consequences for the low-temperature selective catalytic reduction of NO on Cu-CHA catalysts. ACS Catal 11:11616–11625

    Article  CAS  Google Scholar 

  38. Lomachenko KA, Borfecchia E, Negri C, Berlier G, Lamberti C, Beato P, Falsig H, Bordiga S (2016) The Cu-CHA deNOx catalyst in action: temperature-pependent NH3-assisted Selective catalytic reduction monitored by operando XAS and XES. J Am Chem Soc 138:12025–12028

    Article  CAS  PubMed  Google Scholar 

Download references

Funding

No grants or other support were received for conducting this study.

Author information

Authors and Affiliations

  1. Dipartimento di Energia, Laboratorio di Catalisi e Processi Catalitici, Politecnico di Milano, Via La Masa 34, 20156, Milan, Italy

    Nicole Daniela Nasello, Federica Gramigni, Isabella Nova & Enrico Tronconi

  2. Mercedes-Benz AG, 019-C654 RD/PPD, 70546, Stuttgart, Germany

    Frank Hofmann, Simone Dieterich, Marcus Crocoll & Michel Weibel

Authors
  1. Nicole Daniela Nasello
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Federica Gramigni
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Isabella Nova
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Enrico Tronconi
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Frank Hofmann
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Simone Dieterich
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Marcus Crocoll
    View author publications

    You can also search for this author in PubMed Google Scholar

  8. Michel Weibel
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Nicole Daniela Nasello.

Ethics declarations

Conflict of interest

The authors have no conflicts of interest to declare.

Ethical Approval

This work does not contain any studies with human participants or animals perfomed by any of the authors.

Consent to Participate

Not applicable.

Consent for Publication

Not applicable.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary Information

Below is the link to the electronic supplementary material.

Supplementary file1 (DOCX 172 kb)

Rights and permissions

Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Nasello, N.D., Gramigni, F., Nova, I. et al. Transient Redox Behavior of a NH3-SCR Cu-CHA SCR Catalyst: Effect of O2 Feed Content Variation. Top Catal 66, 805–814 (2023). https://doi.org/10.1007/s11244-022-01715-1

Download citation

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11244-022-01715-1

Keywords

Search

Navigation