Phase Behavior and Solubilization of Microemulsions Containing C16mimBr with Different Oil-Water Ratios

Abstract

Abstract The effects of oil-water ratios (α) on the composition of the balanced interfacial layer and the optimum solubilization of microemulsions C16mimBr/butan-1-ol/oil (octane, decane, dodecane)/5% NaCl solution were investigated. As α increases, the alcohol solubility in water and oil phases (Sa) in the microemulsions also tends to increase. The reason is the relatively high solubility of the alcohol in the oil phase compared to the solubility in water. When α increases, the number of surfactant ( n s s ${\rm{n}}_{\rm{s}}^{\rm{s}}$ ) and co-surfactant ( n a s ${\rm{n}}_{\rm{a}}^{\rm{s}}$ ) molecules required to balance the interface layer and the proportion of alcohol in the interfacial layer (AS) increase but the solubilization capacity (SP*) decreases. When the total mass of water and oil is unchanged, the solubilization capacity of the microemulsion systems is lower the higher the relative content of oil is. The effects of different oils, salinity and temperature on the composition of the balanced interfacial layer and the solubilization of microemulsions were also investigated.