Ultrafiltration of an olive oil emulsion stabilized by an anionic surfactant

In this paper we report results on limiting flux in ultrafiltration of an oil in water emulsion stabilized by an anionic surfactant (sodium dodecyl sulfate). Whereas most of previous investigations report variations of filtration flux as a function of pressure at different flow rates, here we also consider the influence of surfactant/oil ratio and emulsion's ionic strength. The present study clearly suggests that filtration of stabilized emulsions exhibits paradoxical experimental similarities with filtration of macromolecules. However, classical film models used for the latter case did not yield proper values for mass transfer coefficients. When using flux models to account for shear enhanced diffusion and pseudo-plastic behavior of the concentrated oil in water emulsions a good agreement between calculated and experimental mass transfer coefficient is obtained. (C) 2000 Elsevier Science B.V. All rights reserved.