Factors Affecting Which Phase Is Dispersed

The study of the interfacial liquid-liquid phase however is complicated by several factors, of which the chief is the mutual solubility of the liquids. No two liquids are completely immiscible even in such extreme cases as water and mercury or water and petroleum the interfacial energy between two pure liquids will thus be affected by such inter-solution of the two homogeneous phases. In cases of complete intersolubility there is evidently no boundary interface and consequently no interfacial energy. On addition of a solute to one of the liquids a partition of the solute between all three phases, the two liquids and the interfacial phase, takes place. Thus we obtain an apparent interfacial concentration of the added solute. The most varied possibilities, such as positive or negative adsorption from both liquids or positive adsorption from one and negative adsorption from the other, are evidently open to us. In spite of the complexity of such systems it is necessary that information on such points should be available, since one of the most important colloidal systems, the emulsions, consisting of liquids dispersed in liquids, owe their properties and peculiarities to an extended interfacial phase of this character. 

Various factors such as size, shape, dispersity, charge, electrolyte, and external stimuli can affect the liquid crystallinity, pitch, domain size, ordering and other properties [9]. The sample suspension was submitted to ultrasonic treatment at 800 W for 8 min. After high power sonication, we could observe a trip-like texture [Fig. 13.6a]. And "tactoid could be observed in the following 24 h, which would aggregate with each other gradually [Figs. 13.6b-e]. Then the pitch characteristic of a chiral nematic phase is clearly observed and the domain size of the chiral nematic... 

Efficient phase separation is critical, since cross-phase contamination has an inherently adverse effect on mass-transfer efficiency. In addition, carryover of solvent in aqueous effluent streams results in loss of solvent from the process, impacting process economics. Phase separation is affected by several physicochemical factors, including the viscosities and densities of the opposing bulk phases and the interfacial tension of the two-phase system. All of these properties contribute to the dimensionless dispersion number, which describes the tendency of two dispersed phases to separate... 

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