Colloids and Surfaces A: Physicochem. Eng. Aspects 375 (2011) 61–67
Influence of external electric field on the polarity of water droplets in
water-in-oil emulsion phase transition
Kaveh Rayat, Farzaneh Feyzi ∗
Thermodynamic Research Laboratory, School of Chemical Engineering, Iran University of Science and Technology, Narmak, Tehran 16846-13114, Iran
a b s t r a c t
The effect of external electric field on the interactions among water droplets in water-in-oil emulsion is
quantified in this work. The obtained contribution is introduced into the potential energy function among
the drops. Using the first order Barker–Henderson perturbation theory, a modified thermodynamic model
has been developed in order to find equilibrium conditions at various temperatures and external electric
fields. The results show that the modification on the dipole–dipole interactions has pronounced effects
on the calculated equilibrium conditions, especially on the predicted required electric field for breaking
the emulsion. Phase diagrams for different drop diameters and adsorption layer thicknesses are plotted
and the final results are discussed compared to the experimental data available in the literature.
© 2010 Elsevier B.V. All rights reserved.
Keywords: Water-in-oil emulsion; Electric field; Induced polarity; Phase transition
