Preparation of octanol emulsion and influence mechanism of electrolyte on its stability

In this study, span 80, tween 80 and sodium oleate were used as emulsifier for the preparation of octanol emulsion through high shear emulsification.Single factor and response surface optimization experiments were conducted to explore the optimum process conditions of preparation emulsion.Based on the DLVO theory, the effect mechanism of electrolyte on emulsion stability was analyzed.The results show that the optimum process conditions of the preparation of emulsion are shear time of 8 min, shear rate of 4 530 r/min, emulsifier dosage of 4.9%, and octanol content of 34.8%.The average particle size of obtained octanol emulsion is (208±1) nm under the optimized conditions.The electrolytes have demulsification effect.The electrostatic repulsion between oil bead is reduced, and the barrier of potential energy curve decreases or even disappears with the increase of electrolyte concentration.This demulsification effect, leads to the coalescence of oil bead, the increases of particle size, the instability of emulsion and even demulsification.The higher cation valence, the stronger the demulsification effect.