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A layer of a water/ethanol/benzene solution, with a composition close to the plait point in the system water/benzene/ethanol, was slowly applied on top of a layer of water of the same dimension avoiding mixing. Immediate spontaneous emulsification was observed in both phases, but most extensively in the aqueous phase. The increase in aqueous phase volume during this initial emulsification stage was significantly less than that, which occurred during a second stage lasting several days of individual transfer of compounds between the layers, with little additional emulsification, The calculated diffusion path for the initial stage of this experiment was consistent with the observation of the emulsification and provided insight on the relative magnitudes of fluxes and the directions of transport of each compound in each phase. [ABSTRACT FROM AUTHOR]

Abstract: Two aqueous solutions on the de-mixing line in the water/benzene/ethanol system formed an O/W emulsion, when mixed. Contacting the solutions without mixing gave a slow spontaneous emulsification over several hours. The emulsion in question was found exclusively in the solution of greater water fraction and the dimension of the emulsion layer expanded as the square root of time. The reduction in the volume fraction the solution with less water was divided by the volume fraction of the emulsion, giving an – albeit exaggerated - measure of the volume fraction of the dispersed phase in the emulsion. It reached 0.6 after 1h, after which it remained constant for 3h. The composition change from the initial stage to the final equilibrium was calculated using a combination of the phase diagram features and earlier diffusion flux calculations in a similar system to estimate the fraction of the compounds transferred between the layers. These transfers were unexpectedly clear-cut, 95wt% of the water in the less water solution was transferred into the water rich solution as was 80% of the ethanol. In the same manner 95% of the benzene in the water rich solution was relocated into the water poor solution. [Copyright &y& Elsevier]

Abstract: Solutions (Or), along the de-mixing line in the system water/benzene/ethanol were contacted with water (W) and the spontaneous emulsification followed by a camera at 40pictures/s. The emulsions formed predominantly in the solution layer for both the aqueous and organic branch of the de-mixing line. These results were projected on the phase diagram of the system and a direct relationship between diagram features and the mechanism of spontaneous emulsification showing a significantly more powerful reaction for solutions of a composition close to the plait point of the system. [Copyright &y& Elsevier]