Experimental and theoretical determination of the particle size of hydrotreating catalysts of different shapes

Equations for calculating the total geometric volume and external area of lobe-shaped catalytic particles as a function of easy-to-determine geometric parameters are presented in this work. Particle density was experimentally determined by the ASTM C-128 standard method, which, together with the average weight of various particles, was used to estimate the total external volume. The calculated total geometric volume was then compared with that obtained by the proposed equations for the purpose of validation. A variety of porous and non-porous particles with different shapes and sizes were employed for validation of both the experimental method and the proposed equations. In the absence of an experimental approach to determine external area, the corresponding equations were validated indirectly by comparing bulk densities determined by the ASTM C-29 experimental method with those calculated with particle density and bed void fraction. Calculated values of external volume and surface were in good agreement with experimental data.