The theory of a globular grain model was used to construct an algorithm for analysing the problem of how the porous structure of heterogeneous catalysts affects their efficiency in model reforming reactions. Our analysis has substantiated the undeniable advantage of applying the bidispersive grain structure since its effectiveness is many times as high as the effectiveness of the monodispersive grain structure. Apparently, the method described in the present paper will be equally efficient when applied to heterogeneous catalysts made use of in other technological processes. (C) 2011 Elsevier Ltd. All rights reserved.