ABSTRACT
The design of the catalyst is of paramount importance to the economics of catalytic processes,[1-5] and the choice of an optimal porous structure is an inherent part not only of catalyst design but also of catalyst selection for the intended technological process. In the assessment of industrial catalysts it is essential to relate catalytic activity on a unit volume basis. This volume-related activity depends on a variety of factors, such as the specific activity of the catalyst relative to the developed surface area, the amount of the surface area in the unit catalyst volume, and the porous structure of the catalyst. The porosity is responsible for the transport of reacting substances and heat in the grains. All these parameters are determined by the conditions of catalyst preparation and the nature of the material.[6,7] A high specific activity can be achieved by controlling the chemical composition of the catalyst under design.[8] However, it is worth remembering that the more active the catalyst, the more difficult becomes the utilization of the catalytic potential because fast reactions induce resistances concomitant with the transport of reagents. It is therefore essential for the designer of a new catalyst to define a priori the required internal surface and the most advantageous pore structure for the intended reaction so as to provide free access of the reacting substances to the surface of the catalyst pores.
