Collect. Czech. Chem. Commun. 1997, 62, 223-237

Effectiveness of Catalyst Extrudate of Tetralobed Cross Section Under Conditions of Influence of Internal Diffusion

Jan Martinec and Jiří Hanika

Department of Organic Technology, Prague Institute of Chemical Technology, 166 28 Prague 6, Czech Republic


The results are summarized of mathematical modelling of the effect of internal diffusion on the rate of m-th order reaction taking place under non-isothermal conditions in the catalyst particle with tetralobed cross section. The effectiveness of the tetralobe-shaped extrudate is compared with that of cylindrical extrudate. The results obtained on the basis of mathematical modelling are confronted with the experimental data obtained on studying the dehydration reaction of cyclohexanol on cylindrical and tetralobed extrudates of gama-alumina under the conditions of influence of internal diffusion. The experimental data are in a qualitative agreement with the theoretical ones and confirm the higher effectiveness of shaped catalyst in comparison with the cylindrical extrudate catalyst.

Keywords: Effectiveness factor; Internal diffusion; Polylobe-shaped pellets; Cyclohexanol dehydration.