Emulsification mechanism

Manoi, K. and Rizvi, S. S. H. (2009). Emulsification mechanisms and characterizations of cold, gel-like emulsions produced from texturized whey protein concentrate. Food Hydro-colloids 23, 1837-1847. 

P. Marie, J.M. Perrier-Cornet, and P. Gervais Influence of Major Parameters in Emulsification Mechanisms Using a High-Pressure Jet. J. Pood Eng. 53,43 (2002). 

J. C. Lopez-Montilla, P.E. Herrera-Morales, S. Pandey, and D.O. Shah Spontaneous Emulsification Mechanisms, Physicochemical Aspects, Modeling and Applications. J. Dispersion Sci. Technol. 23, 219 (2002). 

Figure 5. Schematic Representation of the Proposed Self-Emulsification Mechanism. A. Water Penetration. B. Formation of Liquid Crystal. C. Disruption and Emulsification.

When a surfactant-water or surfactant-brine mixture is carefully contacted with oil in the absence of flow, bulk diffusion and, in some cases, adsorption-desorption or phase transformation kinetics dictate the way in which the equilibrium state is approached and the time required to reach it. Nonequilibrium behavior in such systems is of interest in connection with certain enhanced oil recovery processes where surfactant-brine mixtures are injected into underground formations to diplace globules of oil trapped in the porous rock structure. Indications exist that recovery efficiency can be affected by the extent of equilibration between phases and by the type of nonequilibrium phenomena which occur (J ). In detergency also, the rate and manner of oily soil removal by solubilization and "complexing" or "emulsification" mechanisms are controlled by diffusion and phase transformation kinetics (2-2). 

For the emulsification mechanism to work, however, the interfacial films must be stable. Plus, higher interfacial viscosity increases the stability of emulsions and oil lamellae. Cooke et al. (1974) reported that their qualitative data indicated an increase in interfacial viscosity could increase oil recovery under certain conditions. Regardless, experiences tell us a low interfacial viscosity is needed for a higher recovery. 

Injected alkaline concentration and volume appear to vary depending on the recovery mechanism involved. Concentrations are generally lowest for emulsification mechanisms, from about 0.001 to 0.500 wt.%. Higher concentrations ranging from about 0.5 to 3.0 wt.% or even as high as 15.0 wt.% usually have been required for wettability reversal. Generally, a slug of alkaline solution can... 

Miller, C.A. and Raney, K.H. (1993) Solubilization-emulsification mechanisms of detergency. Colloids Surf.A, 74, 169. 

In this paper we report first the spontaneous emulsification mechanisms in the petroleum sulfonate and caustic systems. This is followed by the kinetics of coalescence in alkaline systems for both the Thums Long Beach (heavy) crude oil and the Huntington Beach (less viscous) crude oil. Measurements of interfacial viscosity, interfacial tension, interfacial charge and micellar aggregate distributions are presented. Interrelationships between these properties and coalescence rates have been established. 

Spontaneous Emulsification Mechanisms in Sulfonate and Caustic Systems... 

The spontaneous emulsification mechanisms were determined for the 3% (Active) Petrostep 420 and 1.5% NaCl and 0.58% n-hexanol versus non-pre-equilibrated Salem crude oil (Sulfonate System). The mechanisms were also determined for Thums Long Beach Crude Oil (Well 108 B) versus 0.05 M (0.2% by weight)... 

The recovery of naturally acidic oils by alkaline flooding fits into the phase alteration category. The recovery mechanisms of these floods are varied since the surface active salts, which are formed by the in situ acid-base reaction, can adsorb onto the oil-water interface to promote emulsification or can absorb onto the rock surface to alter wettability. The exact recovery mechanism, recently reviewed by Johnson (3) depends on the pH and salinity of the aqueous phase, acidity of the organic phase and wettability of the rock surface (4,5). In this study an additional alkaline recovery mechanism is explored. This mechanism. Emulsification and Coalescence, depends on the valency of the electrolyte as well as the pH and salinity of the aqueous phase. The Emulsification and Coalescence mechanism for the recovery of acidic oils is similar to the Spontaneous Emulsification mechanism suggested by Schechter et al. (6) for the recovery of nonacidic oils with petroleum sulfonate solutions. 

Emulsification and coalescence The possibility of enhancing oil recovery from porous media by a spontaneous emulsification mechanism has been examined by Schechter and coworkers (6). These researchers postulated that residual oil, which is entrapped after a conventional waterflood, can be mobilized by spontaneous emulsification and subsequent coalescence of small droplets with other... 

Thus, it appears that the high recovery of the buffered borate/ salt system was obtained by an Emulsification and Coalescence mechanism in which the mobilization step was promoted by an emulsification and transient wettability alteration process and in which the production step was initiated by a coalescence process and aided by interfacial film formation. Mobilization of residual oil in the calcium hydroxide floods appear initiated by an emulsification mechanism which swells the residual oil and increases its apparent saturation. Contacting of adjacent ganglia of residual oil is made as the result of swelling of the residual oil with concomitant wettability alteration. The mechanisms by which an emulsification... 

Three different types of microsystem have been reported for the emulsification of a polymerizable liquid (Figure 18.1), namely the terrace-like microchannel device, the T-junction microchannel device and the flow focusing device (FFD). The emulsification mechanism, which is similar for these three devices, proceeds from the breakup of a liquid thread into droplets when the phase to be dispersed is sheared by the continuous and immiscible phase. 

Schuster [59] discussed the different emulsifying devices and the emulsification mechanism. 

For low energy surfaces, i.e. hydrophobic materials such as polyester, a contact angle of less than 90 is usually observed, and small amounts of the oily soil may be removed by hydraulic forces at the soil-water interface, as shown in Figure 12.13a. If the fabric surface is completely covered by oily soil, no location is available for the surfactant solution to reach the fiber surface and undercut the soil. Observation of this emulsification mechanism has been made by many investigators for mineral oils and mineral oil/polar soil mixtures on hydrophobic flat films and... 

Several factors have been studied with regard to their eflfect on the emulsification mechanism for the removal of mixtures of mineral oil and polar organic alcohols or acids from polyester. The rate of emulsification of mineral oil/oleic acid mixtures from polyester films was found to change as the oleic acid content was varied. Other factors such as electrolyte concentration and temperature were also found to have large effects on the rate of soil removal by this mechanism. 

Clear evidence exists that solubilization and emulsification are major factors in removal of oily soils from hydn hobic, synthetic fabrics. Unlike roll-up, in which die interaction of die fribric widi the oily soil and water is the most critical factor, the solubilization-emulsification mechanism occurs primarily at the oil/ detergent solution interface and is therefore directly influenced by the phase behavior of the cmre nding oil-water-surfiictant system. 

Akiyama, E., Kashimoto, A., Fukuda, K., Hotta, H., Suzuki, T., and Kitsuki, T. 2005. Thickening properties and emulsification mechanisms of new derivatives of polysaccharides in aqueous solution. J. Colloid Interface Sci. 282 448-57. 

The so-called self-emulsification is referred to those methods in which the nano-emulsion is just obtained by a dilution process without any inversion of phases. It is also called direct emulsification because the initial emulsion type is that of the intended final emulsion [19]. It should be taken into account that the term self-emulsification is frequently used in the Ulerature to describe emulsification mechanisms, in which not only dilution processes but also processes implying changes in the spontaneous curvature of the surfactant film are involved. Therefore, this terminology is often misleading. 

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