Mass transport phenomena in oil-in-water emulsions containing surfactant micelles: Solubilization

The influence of surfactant type and concentration on the solubilization of n-hydrocarbon emulsion droplets in aqueous solutions of nonionic surfactan t micelles was investigated. Solubilization was monitored by measuring the decrease in droplet concentration with time after n-tetradecane droplets we re suspended in surfactant solutions (Tween 20, Tween 40, Tween 60, Tween 8 0, Triton X-100, Triton SP-190, and Triton SP-175). The kinetics and extent of solubilization increased with surfactant concentration. The solubilizat ion characteristics also depended on surfactant structure, with the interfa cial mass transport coefficient and specific solubilization capacity of the micelles increasing as the HLB number moved from 17 to 12. This study show s that surfactant type and concentration have a pronounced influence on the kinetics and extent of solubilization in micellar solutions.