Effect of surfactant type on electrostatic desetabilization of W/O emulsions

Abstract

The effect of different types of surfactants on the electrostatic destabilization of water-in-oil (W/O) emulsions is the focus of the present research. To this end, W/O emulsions are formulated with a non-ionic surfactant (Span 80) and with an amphoteric surfactant (Soy lecithin) at 3% w/w of the surfactant in the oil phase (paraffin), considering emulsions with two water/oil phase ratios (20/80 and 40/60), the emulsions are characterized according to dilution, bulk density and apparent viscosity test; a direct current (DC) electric field is applied in the observation cell of flat copper electrodes and the Global Destabilization Factor (FDG) is determined as the response variable. The results show that the impact of the electric field on the emulsion depends on its initial stability. The greater the proportion of the dispersed phase, the greater the average droplet size and the wider the droplet size distribution, the greater the destabilization achieved by the electrical treatment, observing a different behavior in the coalescence of the droplets depending on the surfactant. This research is associated with SDG No. 9.