Uso de surfactantes na redução de incrustações em membranas de microfiltração

Abstract

Fouling in membrane separation process is defined by the accumulation of particulates on membrane surface and in its pores. The main goal of this work is to use commercial surfactants (CTAB, SDS and Tween 80) and a biossurfactant (Rhamnolipid) to coat the surface of a commercial microfiltration membrane in order to improve its performance. All membranes, coated and uncoated, were characterized by their surface properties. FT-IR, zeta potential and contact angle evaluations were carried out. Microfiltration tests using Saccharomyces cerevisiae yeast suspension as fouling agent model at different operational conditions were performed. The contact angle and zeta potential results indicated the adsorption of surfactants on the membranes surface due to changes in membrane’s hydrophilicity and superficial charges. In every pressure and flow conditions set, the permeate flux values were increased for all coated membranes in comparison to the uncoated membrane. The long term experiments showed a high stability of the rhamnolipid adsorption on the membrane surface, proving its effectiveness in fouling reduction.