Emulsion phase component mass

The exterior phase was analyzed for phenylalanine concentration and pH. All sample volumes were recorded and used for mass balance determination. Phenylalanine was measured spectrophotometrically at lmax = 257.5 nm. Changes in interior phase volume were calculated using material balances. All material balances closed to within 2%. Interior phase concentrations were estimated by the use of material balances and exterior phase concentrations. The interior phase components of several representative emulsions were measured by analyzing the interior phase components after thermally demulsifying the emulsion samples. These measurements agreed with estimates to within 10%. 

Permeation flux through membrane Reaction rate constant for i-th reaction Bubble-to-cloud phase mass transfer coefficient for component I in cell n Bubble-to-emulsion phase mass transfer coefficient for component i in cell n Cloud-to-emulsion phase mass transfer coefficient for component i in cell n Adsorption constant for CO Equilibrium constant for y-th reaction... 

Bubble-to-emulsion phase mass transfer coefficient for component I in cell n (s )... 

In Equation 5.231, the indexes b, c, and e refer to the bubble, cloud, and emulsion phases, respectively. The mass balance for component i is valid in the bubble phase... 

One of the most important phenomena which may occur at the interface in an extracting emulsion is formation of small particles on the order of 10-50 nm (i.e, a nanodispersion). Formation of a nanodispersion is promoted by the presence of a surfactant and a co-surfactant in the system (5) and by disruption of the equilibrium between the phases of the extracting emulsion (Le. by mass transfer of components of the phases and the solvents through the interface). When microemulsifiers are included in the emulsion to decrease interfacial tension, nanodispersion formation result. The microemulsifiers can diffuse through the interface of the emulsion which results in interface instability and nanodispersion formation. The microemulsifiers can be co-surfactants, such as ethanol and (Uethyl ether (6,7). 

Rubber-Modified Copolymers. Acrylonitrile—butadiene—styrene polymers have become important commercial products since the mid-1950s. The development and properties of ABS polymers have been discussed in detail (76) (see Acrylonitrile polymers). ABS polymers, like HIPS, are two-phase systems in which the elastomer component is dispersed in the rigid SAN copolymer matrix. The electron photomicrographs in Figure 6 show the difference in morphology of mass vs emulsion ABS polymers. The differences in stmcture of the dispersed phases are primarily a result of differences in production processes, types of mbber used, and variation in mbber concentrations. 

Partitioning of components between two immiscible or partially miscible phases is the basis of classical solvent extraction widely used in numerous separations of industrial interest. Extraction is mostly realized in systems with dispergation of one phase into the second phase. Dispergation could be one origin of problems in many systems of interest, like entrainment of organic solvent into aqueous raffinate, formation of stable, difficult-to-separate emulsions, and so on. To solve these problems new ways of contacting of liquids have been developed. An idea to perform separations in three-phase systems with a liquid membrane is relatively new. The first papers on supported liquid membranes (SLM) appeared in 1967 [1, 2] and the first patent on emulsion liquid membrane was issued in 1968 [3], If two miscible fluids are separated by a liquid, which is immiscible with them, but enables a mass transport between the fluids, a liquid membrane (LM) is formed. A liquid membrane enables transport of components between two fluids at different rates and in this way to perform separation. When all three phases are liquid this process is called pertraction (PT). In most processes with liquids membrane contact of phases is realized without dispergation of phases. 

Essential oils or ti-limonene are recovered from oil-water emulsions by steam distillation at a reduced temperature. This is not a typical fractional distillation, as practiced when distilling cold-pressed oil, but rather, it is a bulk separation of the volatile compounds in the condensed vapor. When this distillation is applied to pure ti-limonene, the mass ratio of water d-limonene at atmospheric pressure is in the range of 8-10 1. In the actual oil emulsions, considerably more water must be distilled to recover a given quantity of rf-limonene, because this component is adsorbed by the pulp particles in the emulsion. If the distillation is performed in a continuous manner under pressure, the ratio of water removed per amount of (i-limoncne recovered can be reduced to 3 4 1 (Braddock, 1999). However, when the steam temperature rises above 120°C, recovery of d-limonene decreases due to formation of some water-soluble alcohols and epoxides, which are soluble in the aqueous phase and are not recovered in the d-limonene phase above the condensate. 

Gas-to-liquid mass transfer is a transport phenomenon that involves the transfer of a component (or multiple components) between gas and liquid phases. Gas-liquid contactors, such as gas-liquid absorption/ stripping columns, gas-liquid-solid fluidized beds, airlift reactors, gas bubble reactors, and trickle-bed reactors (TBRs) are frequently encountered in chemical industry. Gas-to-liquid mass transfer is also applied in environmental control systems, e.g., aeration in wastewater treatment where oxygen is transferred from air to water, trickle-bed filters, and scrubbers for the removal of volatile organic compounds. In addition, gas-to-liquid mass transfer is an important factor in gas-liquid emulsion polymerization, and the rate of polymerization could, thus, be enhanced significantly by mechanical agitation. 

For membrane processes involving liquids the mass transport mechanisms can be more involved. This is because the nature of liquid mixtures currently separated by membranes is also significantly more complex they include emulsions, suspensions of solid particles, proteins, and microorganisms, and multi-component solutions of polymers, salts, acids or bases. The interactions between the species present in such liquid mixtures and the membrane materials could include not only adsorption phenomena but also electric, electrostatic, polarization, and Donnan effects. When an aqueous solution/suspension phase is treated by a MF or UF process it is generally accepted, for example, that convection and particle sieving phenomena are coupled with one or more of the phenomena noted previously. In nanofiltration processes, which typically utilize microporous membranes, the interactions with the membrane surfaces are more prevalent, and the importance of electrostatic and other effects is more significant. The conventional models utilized until now to describe liquid phase filtration are based on irreversible thermodynamics good reviews about such models have been reported in the technical literature [1.1, 1.3, 1.4]. 

Asua et al. [121] and Nomura and Fujita [122,123] have analysed the case of oil-soluble initiators theoretically. The latter group [124,125] has verified the conclusions experimentally for styrene with azobis-isobutyronitrile as initiator. Below the cmc of the emulsifier suspension polymerization occurs in the monomer droplets but, in the presence of emulsifier micelles many more much smaller latex particles are produced and emulsion polymerization kinetics becomes dominant. Only the portion of the initiator partitioned into the water phase is significant in the initiation of the emulsion polymerization. The molar mass distribution of the polymer obtained is bimodal initially [125]. The molar mass of the polymer produced by suspension polymerization in the droplets is the same as that produced by bulk polymerization under comparable conditions and only about one-hundredth of that of the emulsion polymer. Wth increase of conversion the contribution of the lower molar mass component to the overall molar mass distribution becomes insignificant. 

Mixed emulsions are so called because they are obtained from the mixing of two simple emulsions that differ by the compositions of the dispersed phases. The mixing is done gently in order to avoid coalescence at the very maximum. The resulting emulsion has flie particularity of containing droplets that are different in composition and close togeflier (Fig. 14). Should the medium wherein they are dispersed be permeable to their components then mass transfers between... 

In the preparation of semi-interpenetrate network (semi-IPN), collagen can be used as free component or crosslinked to chemicals. Synthesis of semi-interpenetrate network by polymerization reactions is carried out according to the literature data by a few methods, respectively mass polymerization or solution-, suspension-, emulsion-, gas phase- or plasma-induced polymerization. 

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