EFFECTS OF ELECTROLYTE ON THE ELECTROKINETIC PROPERTIES OF TOLUENE-IN-WATER MINIEMULSIONS

The electrokinetic sonic amplitude (ESA) is measured for toluene-in-water miniemulsions stabilized by cetyl alcohol (CA) and 10 mM sodium lauryl sulfate (SLS). It is shown that the effects of electrolyte on the electrokinetic properties of the miniemulsions can be followed through the effect on the ESA to the point of coagulation (CCC). The data clearly show a maximum in the ESA as the electrolyte concentration is increased in the low concentration region up to 10 mM which is likely due to the displacement of CA adsorbed at the o/w interface by SLS and/or co-ion adsorption. The maximum is also detected in the electrophoretic ζ potentials. © 1991.