Solid-liquid systems diagram

Figure 8.23 (Solid + liquid) phase diagram for (. 1CCI4 +. yiCHjCN), an example of a system with large positive deviations from ideal solution behavior. The solid line represents the experimental results and the dashed line is the ideal solution prediction. Solid-phase transitions (represented by horizontal lines) are present in both CCI4 and CH3CN. The CH3CN transition occurs at a temperature lower than the eutectic temperature. It is shown as a dashed line that intersects the ideal CH3CN (solid + liquid) equilibrium line.

Shalaev, E. Yu., Kaney, A. N. Study of the solid-liquid state diagram of the water-glycin-suchrose system. Cryobiology, 31, p. 374-382, 1994. Copyright 1994 Academic Press Inc. 

The T-x diagrams for binary solid-liquid systems can be categorized into four primary types ... 

Analysis of the growth process by LPE usually stipulates an equilibrium boundary condition at the solid-liquid interface. The solid-liquid phase diagrams of interest to LPE are those for the pure semiconductor and the semiconductor-impurity systems. Most solid alloys exhibit complete mis-... 

Figure 14.23 (Solid + liquid) phase diagram for il,4-C6H4(CH3)2 + X2CCI4. A congruently melting addition compound with the formula CCl4-l,4-C6H4(CH3)2(s) forms in this system.

Figure 14.27 (Solid + liquid) phase diagram for (xi Ag + j Au) at p = 0.1 MPa, an example of a system with complete miscibility in both the liquid and solid states.

Figure 14.29 shows the (solid + liquid) phase diagram for (benzene + hexafluoro-benzene). A congruently melting solid molecular addition compound with the formula QFU-CeFe ) is evident in this system.26 The rounded top of the freezing curve (solid line) for the addition compound results from almost complete dissociation of the addition compound in the liquid mixture. In other words, benzene and hexafluorobenzene act as independent molecular species in the liquid state and combine together as the addition compound only in the solid state. 

Chapter 14 describes the phase behavior of binary mixtures. It begins with a discussion of (vapor -l- liquid) phase equilibria, followed by a description of (liquid + liquid) phase equilibria. (Fluid + fluid) phase equilibria extends this description into the supercritical region, where the five fundamental types of (fluid + fluid) phase diagrams are described. Examples of (solid + liquid) phase diagrams are presented that demonstrate the wide variety of systems that are observed. Of interest is the combination of (liquid + liquid) and (solid 4- liquid) equilibria into a single phase diagram, where a quadruple point is described. 

Representation of High-Dimensional Solid-Liquid Phase Diagrams for Ionic Systems, AIChE J.,... 

Figure 2-21 is a generic solid-liquid phase diagram in which compounds A and B form a solid solution in the presence of solvent. As shown in the figure, the equilibrium liquid composition varies with the equilibrium solid composition. Therefore, as long as the overall composition of the system lies within the triangular area (not along the boundary line), it is impossible to obtain pure sohd compounds. 

To demonstrate the general freezing behavior of a binary mixture, we present the solid-liquid phase diagram for systems of ethanol and water at 1 atm in Fig. 8.1. The solid line with the filled symbols is the freezing curve of water in the mixture. Above the curve the solution is completely liquid below the curx-e, it is a liquid mixture coexists with solid water (i.e., ice). At this pressure, pure water freezes at 273.15 K. As ethanol is added to the solution, the temperature at which ice begins to form in gradually decreases. 

The solid-liquid state diagram of the GB-water system shown in Figure 52.3 was constructed from data obtained in the present study supplemented by the existing ones (Landolt-Bornstein, 1962). As the DSC heating scans obtained with the system in the concentration above 60 wt% were complicated, there remained ambiguity in the diagram about the existence of crystal hydrates other than monohydrate. Although eutectic... 

Solid-liquid state diagram of glycinebetaine-water system. Solubility curve (T,) was supplemented by the data in Landolt-Bornstein, Losungsgewichite von Festen und Fliissigen Stoffen in Fliissigkeiten, 6th Ed., Vol. ll/2b, 3-446, Springer, Berlin, 1962. With permission. 

Figure 12.4-2 Solid-liquid phase diagram for the cobalt-copper system. The melting point of copper is 1356.6 K, and the melting point of cobalt is 1768 K.

FIGURE 9.26 The thermodynamic equilibrium phase diagram for a binary solid-liquid system. The eutectic temperature and species A mass fraction and a dendritic temperature and liquidus and solidus species A mass fractions are also shown. 

In Fig. 9.26, the thermodynamic equilibrium, solid-liquid phase diagram of a binary (species A and B) system is shown for a nonideal solid solution (i.e., miscible liquid but immiscible solid phase). The melting temperatures of pure substances are shown with Tm A and Tm B. At the eutectic-point mole fraction, designated by the subscript e, both solid and liquid can coexist at equilibrium. In this diagram the liquidus and solidus lines are approximated as straight lines. A dendritic temperature T and the dendritic mass fractions of species (p)7(p)s and (p)equilibrium partition ratio kp is used to relate the solid- and liquid-phase mass fractions of species (p)7(p)J and (p)f/(p)f on the liquidus and solidus lines at a given temperature and pressure, that is,... 

All the DSC methods of purity determination depend on the applicability of the van t Hoff equation. This restricts the method to systems where the impurity forms a simple eutectic phase diagram with the major component that is, the impurity or impurities are soluble in the melt and the components do not form solid solutions (53). Use of the van t Hoff equation assumes that the solution of impurity in major components above the melting point is an ideal solution in the thermodynamics sense. Also, the method assumes that the solid-liquid system is essentially in true thermodynamic equilibrium during the measurements. Failure to meet any of these conditions will lead to erroneous results. Other possible errors are associated with the instrumentation employed. This involves the use of the smallest possible sample size consistent with homogeneity (50), proper encapsulation to minimize temperature gradients within the sample, and the slowest possible heating rate lo approach equilibrium conditions. It is recommended that the melting... 

From a phase rule standpoint, there is no difference between a liquid-liquid or a solid-liquid system. Phase equilibrium data for a three-component mixture of solute, solid, and solvent at constant temperature and pressure can therefore be represented on equilateral or right-triangular, x-y, or mass ratio diagrams. 

Figure la Solid-liquid phase diagram for the system water-KCl, showing the eutectic point at 262 K. This is the only point at which equilibrium exists between the three phases ice (crystal), KCl (crystal) and saturated solution... 

---