Design of Catalyst Morphology Tailored to Process Needs

Abstract

In heterogeneous catalysis the size and shape of the solid catalyst particles and the distribution of catalytic active material within them can be varied according to process requirements. Aside from demands on catalyst morphology dictated by the choice of process mode (fluidized-bed, fixed-bed, moving-bed or slurry), chemical kinetics and diffusion determine optimal size and shape of catalyst particles. In cases where the catalyst deactivates by diffusion-limited poisoning processes, the mode of activity distribution within a catalyst particle constitutes another important variable for designing an optimal catalyst. Precise tailoring of catalysts can contribute to pollution prevention. This is certainly true for automotive catalysis, where the monolith catalyst is an example of a sophisticated design adapted to the specific requirements of the application.