A dynamic nonisothermal model for triphase catalysis in organic synthesis

Abstract

Phase-transfer catalysis has been in use for over 3 decades, but triphase catalysis, where the phase-transfer catalyst is immobilized on a solid support, is of much more recent origin. Despite its significant advantages over soluble phase-transfer catalysts, triphase catalysis has not attracted industrial attention. One of the main reasons for this lack of industrial interest is the insufficient understanding of the complex diffusion-reaction processes involved. Significant insights into this problem can be gained by mathematical modeling of these reaction systems. Unfortunately, while a few studies have been reported on the mathematical modeling of triphase catalysis, none of them address the important problem of nonisothermal effects. In the present paper we develop a dynamic model for triphase catalytic systems that includes intraparticle heat-transfer effects. An important conclusion is that the catalyst exhibits maximum effectiveness (with an effectiveness factor greater than 1) at a particular reaction time and that it can be tailored to physically realize this enhanced conversion.