Optimization study of octane-in-water emulsions by sedimentation field-flow fractionation

Abstract The droplet size distributions of octane-in-water emulsions have been studied by sedimentation field-flow fractionation (SdFFF). Initially, the experimental parameters of the SdFFF experiment were examined to optimized these conditions for an octane emulsion stabilized by sodium dodecyl sulfate (SDS). The carrier flow-rate had a large impact on sample recovery. Resolution of the various size species was optimized by using the appropriate field strength and relaxation parameters. Comparison of the SDS emulsion to a similar SDS emulsion with added sodium chloride and to an non-ionic system, Brij 35, confirmed the sensitivity of the SdFFF method to differences in size distribution. Examination of the droplet size distribution over a 70-h period provided insights into the stability of these systems.