Transient solute adsorption incorporated modeling and simulation of unstirred dead-end ultrafiltration of macromolecules: An approach based on self-consistent field theory

Abstract

An unsteady state mass transfer model of unstirred dead-end ultrafiltration module has been developed in the present study. The dynamic membrane surface concentration is evaluated using a modified self-consistent field theory, which enables the development of an algorithm to incorporate the contribution of solute adsorption in the membrane surface concentration dynamics. Knowing the corrected membrane surface concentration, permeate flux and permeate side concentration is determined using osmotic pressure model and flux–rejection relation as predicted by irreversible thermodynamics. The time evolution of all the different process variables is achieved by solving two component balance equations developed at the membrane surface and in the solution phase respectively. The basic feature of the model is the incorporation of adsorbed fraction in the unsteady state membrane surface concentration. For the validation of the proposed model, experiments were conducted with Bovine Serum Albumin (BSA)/water as feed in a standard unstirred batch ultrafiltration module fitted with Polyethersulfone (PES) membrane of 30 kDa molecular weight cut-off (MWCO). The model predicted flux and the permeate concentration were found to be in good agreement with the experimental data.