Dielectrophoretic Demulsification of O/W Emulsion

In this paper the mechanisms of droplet - droplet coalescence of nano emulsion under the effect of non-uniform electric field using AC electric field and three coaxial cylinders is presented. Electric coalescence can be affected by different factors such as voltage, temperature, residence time and especially oil volume percentage in continuous phase. Results indicate that when oil volume percentage increases, the separation efficiency and the diameter of dispersed drops increase as well. It means that lower electric field intensity (E) is needed to demulsify oil of higher volume percentage. All tests have been done in constant frequency of 50 HZ. Values of zeta potential ( ) which indicate the stability of emulsion have been calculated for different volume percentages of oil in water. In this paper, non-uniform electric field (DEP) is used to separate dispersed drops of xylene in water. In non-uniform electric field, a force will be opposed in charged drops depending on the differences of electric conductivity in dispersed drops. The surrounding medium can cause to move them to the area of higher or lower electric field. The size of drops and the values of zeta potential have been determined using nano zetasizer instrument

کلیدواژه ها:

Non-uniform electric field ، Electric coalescence ، Oil in water emulsion ، Stability ، Demulsification ، Zeta potential