Solute Polarization and Cake Formation in Membrane Ultrafiltration: Causes, Consequences, and Control Techniques

Abstract

In the past 5 years, membrane ultrafiltration has gained increasing prominence as a simple and convenient process for concentrating, purifying, and fractionating solutions of moderate-to-high molecular weight solutes and colloids, and for purifying water and other solvents containing such solutes. The emergence of this new molecular separation technique for both laboratory and industrial applications is almost entirely attributable to the development of a family of uniquely structured polymeric membranes which display extraordinarily high hydraulic permeabilities coupled with the capacity to retain even quite small solute molecules.