Selective CO Methanation on Highly Active Ru/TiO2 Catalysts: Identifying the Physical Origin of the Observed Activation/Deactivation and Loss in Selectivity

Ali M. Abdel-Mageed, Daniel Widmann, Sine Ellemann Olesen, Ib Chorkendorff, R. Jürgen Behm*

*Corresponding author for this work

Research output: Contribution to journalJournal articlepeer-review

333 Downloads (Pure)

Abstract

Ru /TiO2 catalysts are highly active and selective in the selective methanation of CO in the presence of large amounts of CO2, but suffer from a considerable deactivation and loss of selectivity during time on stream. Aiming at a fundamental understanding of these processes, we have systematically investigated the physical reasons responsible for these effects, using catalysts with different surface areas and combining time resolved kinetic and in situ / operando spectroscopy measurements as well as ex situ catalyst characterization. This allowed us to identify and disentangle contributions from different effects such as structural effects, adlayer effects such as site blocking effects and changes in the chemical (surface) composition of the catalysts. Operando XANES / EXAFS measurements revealed that an initial activation phase is largely due to the reduction of oxidized Ru species, together with a distinct change in the Ru particle shape, until reaching a state dominated by metallic Ru species (fraction RuO2
Original languageEnglish
JournalA C S Catalysis
Volume8
Pages (from-to)5399-5414
Number of pages16
ISSN2155-5435
DOIs
Publication statusPublished - 2018

Keywords

  • CO methanation
  • Deactivation
  • Selectivity
  • Particle size effect
  • Ru/Tio2
  • XANES
  • EXAFS
  • DRIFTS

Fingerprint

Dive into the research topics of 'Selective CO Methanation on Highly Active Ru/TiO<sub>2</sub> Catalysts: Identifying the Physical Origin of the Observed Activation/Deactivation and Loss in Selectivity'. Together they form a unique fingerprint.

Cite this