A new high temperature reactor for operando XAS: Application for the dry reforming of methane over Ni/ZrO2 catalyst

Abstract

The construction of a high-temperature reaction cell for operando X-ray absorption spectroscopy characterization is reported. A dedicated cell was designed to operate as a plug-flow reactor using powder samples requiring gas flow and thermal treatment at high temperatures. The cell was successfully used in the reaction of dry reforming of methane (DRM). We present X-ray absorption results in the fluorescence detection mode on a 0.4 wt. % Ni/ZrO catalyst under realistic conditions at 750 °C, reproducing the conditions used for a conventional dynamic microreactor for the DRM reaction. The setup includes a gas distribution system that can be fully remotely operated. The reaction cell offers the possibility of transmission and fluorescence detection modes. The complete setup dedicated to the study of catalysts is permanently installed on the Collaborating Research Groups French Absorption spectroscopy beamline in Material and Environmental sciences (CRG-FAME) and French Absorption spectroscopy beamline in Material and Environmental sciences at Ultra-High Dilution (FAME-UHD) beamlines (BM30B and BM16) at the European Synchrotron Radiation Facility in Grenoble, France.

Stable Cr-MFI Catalysts for the Nonoxidative Dehydrogenation of Ethane: Catalytic Performance and Nature of the Active Sites

“…Using operando X-ray absorption near edge structure (XANES) spectroscopy (at the SAMBA beamline of the SOLEIL synchrotron), we monitored the H 2 -activation from room temperature (RT) to 650 °C of the 0.8Cr/MFI catalyst and its subsequent evolution during the EDH reaction . Extended X-ray absorption fine structure (EXAFS) spectroscopy was also applied after 10 h of EDH.…”

“…Using operando X-ray absorption near edge structure (XANES) spectroscopy (at the SAMBA beamline of the SOLEIL synchrotron), 27 we monitored the H 2 -activation from room temperature (RT) to 650 °C of the 0.8Cr/MFI catalyst and its subsequent evolution during the EDH reaction. 28 Extended X-ray absorption fine structure (EXAFS) spectroscopy was also applied after 10 h of EDH. Through this procedure, the multivariate curve resolution alternating least-squares (MCR-ALS) 29 analysis applied on the 85 spectra (recorded at different steps of the reaction) allowed us to isolate the XANES signatures of pure Cr species formed either in the zeolite cages and/or on its surface: the results from this procedure are summarized in Figure 2.…”

Atomic Scale Insight into the Formation, Size, and Location of Platinum Nanoparticles Supported on γ-Alumina

“…The ground oxide catalyst samples were packed in quartz Mark tubes (10 μm wall thickness) for acquisition. Catalysts previously reduced and transported on sealed ampules under vacuum were re-reduced at atmospheric pressure in a dedicated reactor 69 at 500 °C under a 10 mL/ min flow rate of pure H 2 (>99.9999%). Reference compounds were platinum oxide PtO 2 (Sigma-Aldrich, purity >99.9%, CAS No.…”

Quick-EXAFS and Raman monitoring of activation, reaction and deactivation of NiCu catalysts obtained from hydrotalcite-like precursors

“…It is noteworthy that the methodology described herein can be used for all the processes aiming to produce H 2 from hydrocarbon feedstocks such as steam reforming of methane today used for ~ 50% production of H 2 worldwide, 54 provided of course that the pressure condition necessary for such kind of relevant industrial processes has been reached. Recent developments Please do not adjust margins Please do not adjust margins of reactors used for XAS to study reactions under high pressure 31,55 clearly evidence that the pressure gap to use similar methodology to better understand activation, deactivation and regeneration of steam reforming catalysts is not so far to be overcome. Finally, as a perspective of this work, a new regeneration strategy based on the alternate use of oxidative and reductive gas pulses at 500°C on spent catalysts could be investigated in order to avoid the full reoxidation of metallic active species upon oxidative regeneration as observed herein.…”