Modelling the influence of mass transfer on fixed-bed photocatalytic membrane reactors

Abstract

Photocatalytic membrane reactors have been recently considered as promising reactor types for photodegradation of organic compounds. In this work, a novel reactor concept named fixed-bed photocatalytic membrane reactor (FPMR), which relies on dead-end microfiltration of the catalyst particles, is introduced and studied. A quantitative model for evaluating the influence of mass transfer rate and intrinsic reaction rate on the overall photocatalytic degradation rate is developed and experimentally validated. The results show that the mass transfer rate contributes significantly to the overall reaction rate constant of the FPMR. They further reveal that the overall mass transfer coefficient and overall reaction rate constant of the reactor are greater than 4s−1. Those remarkably high rates are comparable to those of new photocatalytic microreactors which are two to three orders of magnitude higher than traditional photocatalytic reactors. Hence, the new reactor concept forms a powerful approach for designing photocatalytic microreactors.