Formulation by Membrane Emulsification

Membrane emulsification (ME) is a process of forming emulsion by passing a pure dispersed phase or pre-emulsion through a microporous membrane (Fig. 1). The most commonly used membranes for ME are Shirasu porous glass (SPG) membrane and microsieve membranes. In direct ME, fine droplets are produced at the membrane/continuous phase interface by injecting a pure liquid (the dispersed phase) through the membrane into a second immiscible liquid (the continuous phase) (Nakashima et al. 1991). The dispersed phase should not wet the membrane wall, i.e., hydrophobic and hydrophilic membranes are used to produce water-in-oil and oil-in-water emulsions, respectively. At low transmembrane fluxes, uniform droplets can be formed without applying any shear on the membrane surface, solely by the action of interfacial tension (Kukizaki 2009). In order to achieve commercially significant throughputs in ME, the shear stress is applied at the continuous phase/membrane interface, usually by cross flow or...