The effect of fractal dimensionality and dispersion of catalysts on the rate of heterogeneous catalytic reactions involving carbon oxides

Abstract

Analytical relationships describing the relation between the morphology of a heterogeneous catalyst and the rate constant of the controlling stage of a reaction taking place on its surface were obtained. It was shown that the structure of the catalyst surface, expressed in terms of fractal dimensionality, affects both the activation energy and the preexponential coefficient of the rate constant. The equations relating the rate constant of the catalytic reaction to the fractal dimensionality were used for both bulk and deposited catalysts. It was shown that the activation energy of the process increases with increase in the nonuniformity of the catalyst surface, characterized by the fractal dimensionality DF.