Electrokinetic Study of Hexane Droplets in Surfactant Aqueous Solutions

摘要

Use of fine oily-bubble as flotation carrier has been considered attractive in fine particle flotation. In addition to the role of fine particle agglomeration by oily films, the surface properties of air bubbles coated with a thin oil film can be better controlled for the desired selectivity. The electrokinetics of oil droplets in aqueous surfactant solutions was investigated in this paper. Zeta potentials of hexane in the presence of dodecyl amine hydrochloride (DACl), sodium dodecyl sulfate (SDS) and/or palmitic acid (sodium salt, NaPa) were measured as a function of surfactant concentration and solution pH. The results showed that the addition of DACl and SDS could greatly affect the zeta potential of the dispersed hexane droplets while the addition of NaPa exhibited marginal effect. In the presence of any two of these three surfactants, the co-adsorption behavior of surfactants at oil/water interface was observed. The present work clearly shows that the surface charge and hence the surface properties of oil droplets can be finely tuned by controlling the type and concentration of surface active agent to suit the desired flotation needs.