Description of the diffusive–convective mass transport in a hollow-fiber biphasic biocatalytic membrane reactor

Abstract

The substrate transport in a biphasic, biocatalytic, capillary membrane layer has been investigated. The measured data of oleuropein hydrolysis, in olive mill wastewater, have been evaluated in both a well-mixed tank reactor and a polysulphone, biocatalytic, capillary membrane reactor. The β-glucosidase enzyme was immobilized in the sponge layer of the asymmetric, hydrophilic membrane layer. Strong, competitive product inhibition, applying Michaelis–Menten kinetics with product inhibition for evaluation of the measured data, has been obtained in the mixed tank reactor while the reaction did not show inhibition in the biocatalytic membrane layer. Applying the kinetic data for the oleuropein hydrolysis, the performance of a biocatalytic membrane reactor has been discussed under different operating modes. The effect of the lumen radius, membrane thickness, location of the inlet of the substrate, the inlet concentration and Peclet number as well as the effect of the external mass transfer resistances have been discussed and illustrated. It has been shown that all parameters mentioned above can have a strong effect on membrane performance. The model and its presented, so-called forward sweep numerical solution method, where concentration of the first sublayer is given by an explicit expression of closed form, can essentially help the reader estimate the effect of the operating parameters on the performance of a biocatalytic, capillary membrane reactor. The simulation results enable the user to select the right choice between operating conditions, providing a high efficiency membrane reactor.