Bridging the gap between industry and synchrotron: an operando study at 30 bar over 300 h during Fischer–Tropsch synthesis

Abstract

In order to reduce CO₂ emissions, it is necessary to substitute fossil fuels with renewable energy using CO₂ as a carbon feedstock. An attractive route for synthetic fuel production is the Fe- or Co-catalysed Fischer–Tropsch process. A profound knowledge of the catalyst deactivation phenomena under industrial conditions is crucial for the process optimisation. In this study, we followed the structural changes of a Co–Ni–Re/γ-Al₂O₃ catalyst for >300 hours at 30 bar and 250 °C during the Fischer–Tropsch synthesis operando at a synchrotron radiation facility. The advanced setup built for operando X-ray diffraction and X-ray absorption spectroscopy allows simultaneous and robust monitoring of the catalytic activity even over 300 h time on stream. We found three activity regimes for the Co–Ni–Re/γ-Al₂O₃ catalyst during 310 h of operation. Fast decline in activity was observed during the initiation phase in the first hours of operation due to liquid film formation (mass transport limitations). Furthermore, solid state reactions and carbon depositions were found while continuing the exposure of the catalyst to harsh temperature conditions of 250 °C. By using this advanced setup, we bridged the gap between industrially oriented catalysts and fundamental studies at synchrotron radiation facilities, opening up new possibilities for operando characterisation of industrial processes that rely on conditions of up to 450 °C and 50 bar.