Suleiman Mousa (1), Vladimir Novak (2), Robin S. Fletcher (3), Gordon Kelly (3), Monica Garcia (3), Norman Macleod (3), Christopher Parmenter (4), Sean P. Rigby (1)
Chemical Engineering Science. Volume 277 (17 May 2023). DOI: https://doi.org/10.1016/j.ces.2023.118880

Keywords

X-ray computed tomography, FIB SEM, Bulk condensation, Adsorption, Porosity, Diffusion

Abstract

Catalyst pellet fabrication parameters significantly impact final product performance. Tabletted pellets are complex, hierarchical structures that evolve differently over various levels during subsequent processing. Multi-scale porosimetry and multi-modal imaging can, together, encompass all length-scales involved, and, therefore, fully characterise the evolving pellet structure during catalyst reduction and sintering. A random pore-bond network model has highlighted the key pellet structural features determining mass transport, and, thence, was predictive of the impact on mass transfer of controlled modifications to the void space for reduced and aged catalysts. Particular macroporosity, newly induced by reduction and sintering, was critical to mass transport out of proportion to its pore volume fraction. Combined X-ray tomography imaging and percolation modelling showed that reduction and sintering leads to a change (compared to the fresh state) in the initial pellet fabrication parameter that controls mass transport in pellets formed with roll-compacted feed.

How Our Software Was Used

Image analysis and segmentation were carried out in Dragonfly using a deep learning neural network.

Author Affiliation

(1) Department of Chemical and Environmental Engineering, Faculty of Engineering, University of Nottingham, University Park, Nottingham NG7 2RD, UK
(2) Swiss Light Source, Paul Scherrer Institut, Forschungsstrasse 111, 5232 Villigen PSI, Switzerland
(3) Johnson Matthey, P.O. Box 1, Belasis Avenue, Billingham, Cleveland TS23 1LB, UK
(4) Nanoscale and Microscale Research Centre, University of Nottingham, University Park, Nottingham NG7 2RD, UK