Binary liquid system

Yu.Ya. Fialkov, Binary liquid systems, Technika, Kiev, 1969 (in Russian). 

In the previous sections we have been concerned with high-pressure equilibria in systems containing one liquid phase and one vapor phase. We now briefly consider the effect of pressure on equilibria between two liquid phases. In particular, we are concerned with the question of how pressure may be used to induce miscibility or immiscibility in a binary liquid system. 

Second, Schneider s article reviews recent work (notably by Rowlinson, Kohn and co-workers) on phase relations in binary liquid systems where one of the components is much more volatile than the other (D1, D2, E3, M8, R9). Such systems may have lower critical solution temperatures for these systems, an increase in temperature (and, indirectly, pressure) causes precipitation of the heavy component, thereby providing a possible separation technique, e.g., for the fractionation of polymers. 

Spectroscopic Methods, [Biological] Applications of Spectroscopy, EPR, Recent Advances in (Smaller). Spectroscopy, Infrared, Use in Biology (Lecomte). Spectroscopy of Transition-Group Complexes (Jorgensen) Statistical-Mechanical Theory of Transport Processes. X. The Heat of Transport in Binary Liquid Systems (Bearman, Kirkwood, Fixman). ... 

Nakahara, S., Masamoto, H., and Aral, Y. Interfacial tension of two-phase water-alkene binary liquid system. J. Chem. Eng. Jpn., 23(l) 94-95, 1990. 

Wahid, H. Light scattering from binary liquid systems. II. The partial pressure of solutions. Phys. Chem. Liq., 26 171-177, 1993. 

The investigation of viscosities, electrical conductivities, refractive indexes and densities of binary liquid systems of sulphuric acid with nitromethane, nitrobenzene and 0-, m and p-nitrotoluene was made in order to obtain a clearer picture of the behaviour of these binary mixtures, regarding the stability of the addition compounds formed between the components. The application of these methods of physicochemical analysis to a number of binary systems with sulphuric acid [1, 2, 3] has enabled us to get some idea of the way in which the formation and stability of addition compounds affects the liquid phase properties of these systems. The binary systems of sulphuric acid with mononitrocompounds are particularly suitable for comparison with each other, because of the close similarity of the liquid media in these systems, due to comparable values of dielectric constants and liquid phase properties of the mononitrocompounds. The stability of the addition compounds in these systems in the crystalline phase [4] has... 

Heat of Transport in Binary Liquid Systems (Bearman, Kirkwood ... 

The maximum boiling point is that temperature corresponding to a definite composition of a Iwo-coinponenl or multicomponent system al which the boiling point of the system is a maximum. At this temperature the liquid and vapor have the same composition and the solution distills completely without change in temperature. Binary liquid systems that show negative deviations from Raoult s law have maximum boiling points. See Raoult s I xiw and Van t Hoff I,aw. 

Now, we shall ask the following question which is pertinent to the total atomic configuration (i.e., the entropy of mixing) in a binary liquid system ... 

Consider the A-B binary liquid system in equilibrium with the vapour phase at a constant temperature. Is the composition of the vapour the same as that of the liquid Not necessarily. Let s apply the Gibbs-Duhem equation to the liquid phase. 

The original Crawford-Wilke correlation [11] was based on eight different binary liquid systems, the packing of which is listed in Table 7.4. The void fractions for packings had a maximum value of 0.74. The liquid properties ranged as follows ... 

As a third liquid is added to the partially miscible binary liquid system, the ternary (three-component) system is dependent on the relative solubility of the third liquid in the two liquids. If the third substance is soluble only in one liquid of the original binary mixture or if the solubility of the third in the two liquids is considerably different, the solubility of one liquid in the others will be lowered. The upper consolute temperature should be raised or the lower consolute temperature should be lowered in order to obtain a homogeneous solution. On the other hand, if the third substance is soluble to the same extent in both liquids of the binary system, the complementary solubility of the two liquids is increased. This results in the lowering of an upper consolute temperature or the elevation of a lower consolute temperature. 

The viscosities of many binary liquid systems display minima as functions of composition at constant temperature, so that negative values of D are also possible. Yajnik and his coworkers (265 ) long ago observed that very frequently an extremum in the isothermal vapor pressure-composition curve is accompanied by an extremum of the opposite sense in the viscosity-concentration curve. Data are apparently not available for solutions of very low-molecular-weight paraffins in carbon tetrachloride, but minima are found for the viscosities of solutions of CC14 with ethyl iodide, ethyl acetate and acetone, so that a minimum appears quite probable for mixtures of small aliphatic hydrocarbons with carbon tetrachloride. If this were true, the downward trend of the Meyer-Van der Wyk data on C17—C31 paraffins, earlier discussed in connection with the polyethylene plots of Fig. 14, would be understood. It will be recognized that such a trend is also precisely what is to be expected from the draining effect of the hydrodynamic theories of Debye and Bueche (79), Brinkman (45 ) and Kirkwood and Riseman (139). However, the absence of such a trend in the case of polyethylene... 

Figure 12.20 Plots of /] and f2 vs. Xi for a binary liquid system solubility in species 2.

Example 13.2 The enthalpy of a binary liquid system of species 1 and 2 at fix and P is represented by the equation... 

Figure 13.5 shows experimental heats of mixing AH (or excess enthalp He) for the ethanol/water system as a function of composition for seve" temperatures between 30 and 110°C. This figure illustrates much of the vari of behavior found for HE = AH and Vh - A V data for binary liquid system... 

While thermotransport data from experiments on a number of nitrate mixtures are available (4, 10), unfortunately no relative electrotransport mobility measurements have been made for these particular systems and diffusion data are scanty. Isotope effects have been seen with cells permitting only qualitative results. Until a more systematic study has been made on all the relevant effects in one well-defined system, the usefulness of the individual transport property investigations in binary liquid systems, however carefully performed, remains relatively limited. 

Figure 11.4 Excess properties at 323.15 K (SO C) for six binary liquid systems (a) cliloroform(1)/n-heptane 2) (6) acetone(1)/methanoi(2) (c) acetone(l)/ chloroform 2) (d) ethanol(1)/r3-heptane(2) (e) ethanol(1)/chloroform(2) (f) ethanol (1)/water(2)...

Figure 12.13 illustrates the composition dependence of AG, AH, and T AS for six binary liquid systems at 323.15 K (50°C) and approximately atmosphericpressure. The related quantities G , H , and FS are shownfortlie same systemsinFig. 11.4. As witlitlie excess properties, property changes of mixing exliibit diverse beliavior, but again all systems liave certain common features ...

The following is a set of activity-coefficient data for a binary liquid system as determined from VLE data ... 

Possible correlatingequationsfor In yi in a binary liquid system are givenfollowing. For one of these cases determine by integration of the Gibbs/Duhem equation [Eq. (11.96)] the corresponding equation for In yz. Wliat is the corresponding equation for... 

A binary liquid system exhibits LLE at 298.15 K (25°C). Determine from each of the following sets of miscibilitv data estimates for parameters A12 and Aji in the Margules equation at 298.15 K(25°C) ... 

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