ULTRAFILTRATION AND MICROFILTRATION OF SURFACTANT DISPERSIONS - AN EVALUATION OF PUBLISHED RESEARCH

A critial review of literature on the separation of surfactants from a queous streams by membrane processes is given. These processes are ult rafiltration (UF), miceller enhanced ultrafiltration (MEUF), and rever se osmosis (RO). The factors which affect the permeate flux and reject ion of the surfactant and/or electrolyte are considered in detail. Wit h the exception of MEUF studies, most of the published work on surfact ant separation lacks input from surfactant and interface science. Thes e studies indicate that the fouling (gel) layer on the membrane and wi thin the pores essentially controls the permeate flux and rejection ch aracteristics of the separation system. It is therefore essential to u nderstand the physical-chemical nature of the gel layer which is proba bly a direct result of surfactant and electrolyte concentrations and t emperature on the surfactant phase behaviour. The present review also indicates that the mechanism of water and/or surfactant transport thro ugh the membrane and gel layer has not been considered.