Home > Timetable > Session details > Contribution details

Contribution Poster

Budker INP - 2nd and 3rd floors

In situ determination of the active phase in palladium nanocatalyst by X-ray absorption spectroscopy and X-ray diffraction

Speakers

  • Mr. Aram BUGAEV

Primary authors

Co-authors

Content

Hydrogenation of alkynes and alkenes over palladium catalyst is associated with formation of palladium hydrides and carbides phases, which affects the selectivity and catalytic performance of the catalyst. The aim of this study is to investigate the effect of the structural changes on the catalytic properties of the material. We investigated the structural evolution of the industrial palladium-based nanocatalyst in operando conditions during the catalytic hydrogenation of ethylene. The structure of the catalyst was followed by X-ray absorption spectroscopy and X-ray powder diffraction, while the conversion level of ethylene to ethane was controlled by mass spectrometer. We observed that phase transitions occurring in palladium nanoparticles lead to dramatic changes of the catalytic activity. In addition to standard Fourier-analysis of X-ray absorption data and Rietveld refinement of diffraction patterns, analysis of X-ray absorption near-edge structure (XANES) allowed to discriminate between PdH and PdC species having similar fcc structure. The PdC phase and pure Pd phase demonstrated extremely high catalytic activity in ethylene to ethane hydrogenation, while β-PdH showed unexpectedly low activity.