Ternary systems classification

The present paper gives an overview of results on high-pressure phase equilibria in the ternary system carbon dioxide-water-1-propanol, which has been investigated at temperatures between 288 and 333 K and pressures up to 16 MPa. Furthermore, pressure-temperature data on critical lines, which bound the region where multiphase equilibria are oberserved were taken. This study continues the series of previous investigations on ternary systems with the polar solvents acetone [2], isopropanol [3] and propionic add [4], A classification of the different types of phase behaviour and thermodynamic methods to model the complex phase behaviour with cubic equations of state are discussed. 

According to the classification proposed in this paper (Table 1), polymer coacervation is generally observed in binary or ternary systems, in either aqueous or organic liquids. Three main mechanisms govern the process of coacervation in these systems ... 

Thermodynamic constraints to the SAS process can be summarized in the required miscibility between the liquid solvent and the supercritical antisolvent and the insolubility of the solute in the antisolvent and in the solvent-antisolvent mixture. Data are available for various binary mixtures liquid-supercritical fluid and can be described as type I using the classification of van-Konynenburg and Scott. If jet break-up is obtained and mass transfer is very fast, high-pressure VLEs of the ternary system liquid-I-solute-I-supercritical fluid can control the precipitation process. 

In the light of these considerations, a different approach based on ternary system thermodynamics could be considered. However, the phase behavior of temaiy systems could be very complex and there is a considerable lack of data on ternary systems containing a component of low volatility therefore, a possible compromise could be to consider that the solute addition can produce the shift of the mixture critical point (MCP) (i.e., the pressure at which the ternary mixture is supercritical) with respect to binary system VLEs and the modification of this kind of system that is formed according to the van-Konynenburg and Scott classification. ... 

Although the classification of ternary phase behavior is described here at a fixed temperature, it is important to remember that a single ternary system can exhibit all three types of phase behaviors as the temperature of the system changes. Based on our classification of binary phase behavior, type-I ternary phase behavior above the critical temperature of the SCF solvent may revert to type-II or type-III ternary phase behavior if the operating temperature and pressure are adjusted to values near the critical point of the SCF solvent. 

In this section the results on high-spin iron(II) systems are presented before those on iron(III). The latter dominate, and are ordered approximately as follows the major structural classes of Fe203/M203 solid solutions, MFe03 perovskites, MFe03 orthoferrites, M3FesOi2 garnets and other iron(III) oxides approximately in the periodic table classification of the second metal. Any quaternary oxides are included with the most appropriate ternary system. 

Based on s discovery, a systematic and extensive experimental investigation of related ternary systems containing near-critical CO2 as the solvent and two heavier solutes has been carried out. The temperatures, pressures and compositions examined are within the range of conditions at which processes in super- and near-critical fluid technology applications take place. In ternary systems of the nature CO2 + 1-alkanol + alkane critical endpoint data were determined experimentally to characterize the three-phase behavior tig. To explain the observed fluid phase behavior, the binary classification of Van Konynenburg and Scott [5,6] was adapted to ternary systems, see section 2. 

L Earlier Observations on Unexpected Fluid Phase Behavior Patton et al. [4] found unexpected fluid multiphase behavior for the system CO2 + 1-decanol + tetradecane. The two binary border systems CO2 + 1-decanol and CO2 + tetradecane both show type-III fluid phase behavior, see [41] and [10,43], respectively, in the classification of Scott and Van Konynenburg [14,30] (section 2), with its characteristic UCEP For the ternary system, the three-phase surface Ug is... 

Gauter, K., Florusse, LJ., Peters, CJ. and de Swaan Aarons, J. (1996) Classification of and transformations between types of fluid phase behavior in selected ternary systems. Fluid Phase Equilibria, 116,445-453. 

A verj large number of combinations of solvent and nonsolvent are possible all with their own specific thermodynamic behaviour. Table III.8 shows a very general classification of various solvent/nonsolvent pairs. Where a high mutual affinity exists a porous membrane is obtained, whereas in the case of low mutual affinity a nonporous membrane (or better an asymmetric membrane with a dense nonporous top layer) is obtained. It should be noticed that this holds for ternary systems. In case of multicomponent systems with additives the thermodynaics and kinetics change, as do the membrane properties. 

The experimental investigations were and are the main sources of information about phase behavior in ternary systems. In the beginning of the twentieth century Smiths (1910, 1913, 1915) using the topological method and available experimental information has considered 12 versions of complete phase diagrams with various types of fluid phase behavior and solid phase transformations. But it was not a systematic classification. 

The question of how the solvent water would behave around and above its critical point was first addressed by the Dutch chemist Bakhuis Roozeboom and his school, who were experts at measuring and classifying the phase separation of binary and ternary mixtures, including sohd phases. By 1904, Bakhuis Roozeboom had explored the case of the liquid-vapor-solid curve intersecting the critical line of a binary mixture in two critical endpoints and predicted that this would also happen in aqueous solutions of poorly soluble salts, as his successors indeed confirmed in 1910. His experiments and classification scheme pertain to a multitude of both non-aqueous and aqueous binary and ternary systems. 

ABSTRACT. The classification of solid clathrate solutions may be subdivided into three types interstitial solutions, those with the substitution of one guest by another and those with the substitution of the particles in a host framework is given. All these types of solutions are illustrated by experimental (or computed) state diagrams of binary and ternary systems of guest-host and host-guestl-guest2 kinds, where host components are water, urea, thiourea and hydroquinone. 

In this section we give as examples two uses of the theory outlined above (a) the classification of binary phase diagrams, critical behavior, etc. in terms of the intermolecular forces involved, and (b) comparison with experiment for some binary and ternary systems. 

The classification system described earlier is limited to the simplest kinds of individual melts and is not intended to include mixtures. However, molten mixtures of these different classes of compounds are often more practical solvents than the melts of the individual compounds, due to their much lower melting points and other favorable properties, and this system of classification can usually be extended to these mixtures. For example, the very popular molten LiCl-KCl eutectic mixture is simply a binary ionic melt, whereas molten NaN03-KN03-LiN03 is a ternary polyanionic melt. Interestingly, the equimolar molten mixture of the simple ionic salt NaCl (a) and the molecular compound A1C13 (d) produces a simple polyanionic salt melt (b) composed of Na+ and A1C14 ions ... 

Analysis of the soluble G-bead assembly provides a complementary classification of full and partial agonists, based on their distinct abilities to assemble ternary complexes (LRG). It appears that the behavior of receptors and entire ligand families can be described by the simple ternary complex model alone (Fig. 2A). The analysis provides estimates for the ligand-dependent equilibrium constants that govern the simple ternary complex model. Unique, potentially intermediate, conformational states of the receptor defined by interactions with a particular ligand are characterized by individual binding constants. While these data do not directly show these different conformational states, the bead system appears to act as a... 

As an example of this type of work. Table 6.2 lists the data of known phase diagrams of MeX -Me X-Me X system (here X = F, Cl, Br, I Me is polyvalent metal Me and Me are monovalent metals). Class 1 denotes the systems with ternary intermediate compound formation, and class 2 denotes the systems without ternary intermediate compound formation. SVC method is used for the classification of systems of these two types. 

The formability of intermetallic compounds can be investigated by SVM and the atomic parameters suitable for metallic systems, i.e., Midema s electronegativity (< )), metallic radius (R), number of valence electrons (Z) of free atom and parameter and their functions. For example. Table 6.3 lists the data about the formability of ternary intermetallic compounds and related atomic parameters of known Mg-containing ternary alloy systems. By support vector classification with Gaussian kernel, the rate of correctness of classification is 100%, and the rate of correctness of prediction in LOO cross-validation is 94.9%. 

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