Designing Better Performing FCC Catalysts

Designing Better Performing FCC Catalysts


Researchers at the University of Utrecht, University of Gottingen, DESY, and Albemarle have made major advances understanding the coking process in Fluid catalytic cracking (FCC) catalyst. Carbon deposition (i.e., coking) is one of the main factors contributing to catalyst deactivation. It involves a complex interplay of processes taking place at different length and time scales. The carbon deposition reduces catalyst activity by limiting diffusion and blocking active sites. However, characterizing coke formation and its effects has been challenging as it involves both the organic and inorganic phase of the catalyst and length scales from the atomic scale to the scale of the catalyst body. Using advanced imaging techniques, it was possible to visualize in 3-D the distribution, effect, and nature of carbon deposits in the macropore space of the entire catalyst particle. These findings provide direct evidence of metal poisons promoting coke formation, pore clogging caused by coke, and a correlation between carbon nature and its location. These results provide a better understanding of the coking process and its relation to catalyst deactivation. We expect that these new insights will aid us in designing better performing FCC catalysts, which are highly coke selective and more deactivation resistant.

For more information, and to read this ground-breaking work, please visit: 3-D X-ray Nanotomography Reveals Different Carbon Deposition Mechanisms in a Single Catalyst Particle*

This video (also found in the supporting information section of the work) illustrates the co-location of Fe and carbon deposits within a FCC catalyst particle. A sub-volume of the catalyst particle surface is inspected showing the distribution of individual coke clusters in the particle and a large cluster (yellow) on the surface of the particle, filling dips and dents in the catalysts’ surface. At the 13 second time marker, the 3-D Fe distribution is added (orange color map) showing how Fe is located mainly in the surface of the catalyst particle, while surface coke is clearly deposited on the surface of the catalyst, but in close vicinity to the elevated Fe concentration in the surface.

*Reference: M. Veselý, R. Valadian, L. Merten Lohse, M. Toepperwien, K. Spiers, J. Garrevoet, E. T. C. Vogt, T. Salditt, B. M. Weckhuysen, F. Meirer, ChemCatChem 202113, 2494. For more information about ChemCatChem, please click here.