Emulsion Catastrophic Inversion from Abnormal to Normal Morphology. 3. Conditions for Triggering the Dynamic Inversion and Application to Industrial Processes

Abstract

The catastrophic emulsion inversion from abnormal to normal morphology is produced in different conditions, as far as the experimental protocol is concerned. Far from optimum formulation, the inversion is found to take place when the fraction of the dispersed phase, which may be a single phase or an inner emulsion of a multiple emulsion, reaches a critical packing value. Near optimum formulation, a so-called low-tension streaming-bicontinuity regime is found to happen instead of an emulsion morphology. The phenomenology is used to interpret the emulsification of viscous oil phases in industrial processes.

Phase inversion emulsification: Current understanding and applications

“…On the other hand, when HLD N 0 (HLB b 10) the system is largely affected by addition rate and stirring speed. Similar results have been reported also by Tyrode et al [101].…”

“…For high addition rate the phase inversion seems to be delayed but happens in short time scales without displaying multiple emulsion morphology [100]. The conditions to trigger emulsion from abnormal to normal have been investigated in general [101]. The inversion from abnormal o/w to normal w/o emulsions by stirring and without the internal phase addition [98] has been also shown to be affected by multiple emulsion development.…”

“…Good agreement has been found for the upper limit of the ambivalent zone, whereas the lower one is often underestimated. Salager et al [84,93,101] argued that this kind of kinetic competing phenomenon approach (i.e., breakup vs coalescence), even if satisfactory from a mere physical point of view, is still difficult to handle for quantitative features, being dependent on too many variables yet not fully mastered.…”

Influence of a surfactant or salt on phase inversion in a water–oil pipe flow

“…He presents a formulation-composition map for phase inversion, which shows how the composition of the mixture at which the dispersion inverts is changing with surfactant affinity difference (SAD). Zambrano et al (2003), Mira et al (2003), Tyrode et al (2003), Sajjadi et al (2003), Tyrode et al (2005), Rondón-Gonzaléz et al (2006a,b) show how the HLD-factor (hydrophilic-lipophilic deviation from an optimum formulation), which is a less complicated concept than SAD, influences phase inversion. When HLD < 0 the surfactant exhibits a stronger affinity to oil than to water, for HLD > 0 it is the other way around.…”

“…When HLD < 0 the surfactant exhibits a stronger affinity to oil than to water, for HLD > 0 it is the other way around. Tyrode et al (2003Tyrode et al ( , 2005 show that for HLD < 0 two types of dispersion are possible: a dispersion with multiple drops consisting of oil droplets in water drops in oil, and a dispersion with clean oil drops in water. When HLD > 0 there are again two dispersion types: a dispersion with multiple drops consisting of water droplets in oil drops in water, and a dispersion with clean water drops in oil (see also Fig.…”