Electrokinetic Study of Hexane Droplets in Surfactant Solutions and Process Water of Bitumen Extraction Systems

The effect of surfactant and inorganic salts on the electrokinetics of bitumen and model oil (hexane) in aqueous solution was studied. The zeta potentials of the hexane droplets became less negative without changing the isoelectric point (iep) for increasing inorganic electrolyte concentration. The addition of dodecylamine hydrochloride (DAH) caused a drastic change in the zeta potentials, with a progressive shift of the iep toward a higher pH with increasing DAH concentration. With the addition of sodium dodecyl sulfate (SDS), the zeta potential of the hexane droplets became more negative without a measurable iep. Virtually no change in the zeta potentials of the hexane droplets was observed when palmitic acid was added. Only when a combination of DAH, SDS, NaPa, and inorganic electrolyte was added together could the measured electrokinetic behavior of hexane droplets in the resultant aqueous solution simulate that of hexane droplets in the process water from an industrial bitumen extraction process or b...