Time-resolved operando X-ray absorption study of CuO-CeO2/Al2O3 catalyst during total oxidation of propane

Konstantinos Alexopoulos, Mettu Anilkumar, Marie Françoise Reyniers, Hilde Poelman, Sylvain Cristol, Veerle Balcaen, Philippe M. Heynderickx, Dirk Poelman, Guy B. Marin

Research output: Contribution to journalArticlepeer-review

21 Scopus citations

Abstract

The local structure of the copper phase of a CuO-CeO2/Al2O3 catalyst and its activity for the total oxidation of propane have been studied under working conditions, using time-resolved X-ray absorption spectroscopy (XAS) in transmission mode at the Cu K edge coupled with on-line mass spectrometry (MS). In the temperature range of 573-723 K, the copper phase of the catalyst remains oxidized (i.e. Cu2+) during total oxidation reaction conditions (1%C3H8-5%O2/He), while three species are present (i.e. Cu2+, Cu1+ and Cu0) during reduction (2%C3H8/He) and re-oxidation (10%O2/He) treatments where a two-step mechanism is found. Catalyst reduction is fully reversible, as the Cu2+ nature of the catalyst is recovered after a reduction-oxidation cycle. Re-oxidation of the catalyst is two orders of magnitude faster than its reduction and has an apparent activation energy of 24 kJ/mol. On the other hand, catalyst reduction requires an apparent activation energy of 70 kJ/mol, which is equal to the apparent activation energy determined under total oxidation reaction conditions. These results give support to a Mars-van-Krevelen reaction scheme with the copper phase of the catalyst being close to a fully oxidized state.

Original languageEnglish (US)
Pages (from-to)381-388
Number of pages8
JournalApplied Catalysis B: Environmental
Volume97
Issue number3-4
DOIs
StatePublished - Jun 18 2010

All Science Journal Classification (ASJC) codes

  • Catalysis
  • Environmental Science(all)
  • Process Chemistry and Technology

Fingerprint Dive into the research topics of 'Time-resolved operando X-ray absorption study of CuO-CeO<sub>2</sub>/Al<sub>2</sub>O<sub>3</sub> catalyst during total oxidation of propane'. Together they form a unique fingerprint.

Cite this