Miscibility liquid-phase

As discussed by Frankemfeld and Li(28) and del Cerro and Boey(29), liquid membrane extraction 28,29) involves the transport of solutes across thin layers of liquid interposed between two otherwise miscible liquid phases. There are two types of liquid membranes, emulsion liquid membranes (ELM) and supported liquid membranes (SLM). They are conceptually similar, but substantially different in their engineering. 

To solve Equation (18), we construct the inhomogeneous site-site direct correlation function Coy (ri, F2) by the following procedure [47]. In the spirit of the approximation (3) for simple atomic fluid, we span it between the homogeneous site-site direct correlation functions c y (r p ) of coexisting bulk phases i with site densities p K (Here vector p denotes a set of densities [pa] for all sites a.) For an interface of two immiscible/partially miscible liquids, phase 1 with density p = p[ , is rich in component I and poor... 

When a material system, in which liquid phases predominate, is stirred, this action can result in miscible liquid phases forming a molecularly homogeneous mixture ( solution ). In the case of immiscible liquids, on the other hand, a dispersion (possibly an emulsion ) will result. If stirring is performed to increase heat or mass transfer, the purpose is to accelerate this operation and the inherent mixing of the liquid phases is of secondary importance. 

Dialysis involves the mass transference between two miscible liquid phases (the donor and acceptor solutions) separated by a liquid membrane through which some chemical species are likely to pass. Miscibility between the donor and acceptor solutions is inherent to dialysis and distinguishes it from e.g., liquid—liquid extraction, osmosis and ultrafiltration [271], These latter two membrane-based separation approaches tend to occur concomitantly with dialysis and involve the solvent rather than the solute crossing the membrane. In osmosis, the driving force towards separation is the concentration difference involved whereas in ultrafiltration, also called reverse osmosis, the driving force is an applied pressure that forces the solution across the membrane. 

Two partially miscible liquid phases may be contacted for extraction purposes in a discontinuons or stage-wise manner in cofuntus where the stages take the fomi or perforated pietes, fitted with dowacomers to facilitate flow of the continuous phase. Bubble-cap plates have been found ineffective in extraction, because of the lower density diffntunce. lower Interfacial tension, and higher vjsersity of the dispeise phase, compared to gas-liquid systems. 

This is the upper consolute temperature for a Margules mixture. Note that the Margules equation does not have a lower critical solution temperature (i.e., there is no rolution of Eq. 11.2-11 for which Eq. 11.2-10b is satisfied). Thus the two partially miscible liquid phases of a Margules mixture cannot be made to combine by lowering the temperature. 

In this section we consider a system of two components in two partially miscible liquid phases. The temperature-composition diagram of this system is represented in Fig. 9-12. The liquids are completely miscible above the critical temperature T. The curve AC represents the equilibrium temperature as a function of the composition of liquid phase 2 the curve BC represents the equiUbrium temperature as a function of the composition of the liquid phase 1. 

Sorptive extraction techniques are based on the distribution equilibria between the sample matrix and a non-miscible liquid phase. Matrices are mostly aqueous and the non-miscible phase is often coated onto a solid support. Analytes are extracted from the matrix into the non-miscible extracting phase. Unlike adsorption techniques, where the analytes are bound to active sites on the surface, the total volume of extraction phase is important. Extraction of analytes depends on the partitioning coefficient of solutes between the phases (Ridgway et al., 2007). Two extraction techniques are commonly employed solid phase microextraction (SPME) and stir-bar sorptive extraction (SBSE). 

Fig. 2 Diagrams of basic types of two-component system where vapor and two partially miscible liquid phases are in equilibrium...

Many liquid products are emulsions, systems of at least two or more immiscible or poorly miscible liquid phases, for example oil and water. Examples of these kinds of products are milk, butter, mayonnaise and cosmetic creams. 

In liquid-liquid extractions, at least one component in the original mixture to be separated must be soluble in the new solvent, while the other components are not as soluble. Thus, we are concerned with two separate immiscible, or only partially miscible, liquid phases and at least one solute component. These two phases must be mutually insoluble or exhibit a very limited mutual solubility. However, the transferred component that is to be separated is soluble in both liquid phases. 

Solvent extraction is defined as the transfer of solutes between two immiscible or only partly miscible liquid phases. As a rule, an aqueous phase is brought into... 

Consider a mixture of benzene (1) and a proprietary organic molecule (2) that is in vapor-liquid equilibrium at 70°C. The proprietary molecule and benzene form a completely miscible liquid phase, but the proprietary molecule has a negligible vapor pressure. The activity coefficient at infinite dilution for this system is reported to be ") = 99.7. As best you can, determine the equilibrium mole fraction of the proprietary molecule in the fiquid when the system pressure equals P. ... 

At a 300 K and 1 bar, a binary mixture of species a and b form two partially miscible liquid phases. The following activity coefficients at infinite dilution are reported 7 = Sandy = 15. Using the three-suffix Margules equation, determine the composition of two liquid phases in equilibrium. 

Consider a binary liquid mixture of hexane (1) and acetone (2). At 15°C and 300 bar, this mixture forms two partially miscible liquid phases. Phase a has 20 total moles with = 0.2, while phase /3 has 10 total moles with xf = 0.8. The following data are available at 15°C ... 

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