Equilibria in multiple-component systems

Covering chemical phenomena of 1,2, 3, 4, and multiple component systems, this standard work on the subject (Nature, London), has been completely revised and brought up to date by A. N. Campbell and N. O. Smith. Brand new material has been added on such matters as binary, tertiary liquid equilibria, solid solutions in ternary systems, quinary systems of salts and water. Completely revised to triangular coordinates in ternary systems, clarified graphic representation, solid models, etc. gth revised edition. Author, subject indexes. 236 figures. 505 footnotes, mostly bibliographic, xii -f- 494pp. 536 x 8. 

Polyoxymethylene (POM) can be synthesized cationically not only from TXN but also from formaldehyde (FA) and 1,3,5,7-tetraoxocane (TTXN). In fact, when TXN polymerizes all these products coexist in multiple equilibria. The polymer is crystalline and precipitates out from the reaction mixture. Thus, the concentration of the components of the system depends on the thermodynamics of the equilibria ... 

In the copolymers described in Sect. 3.4, the multiple components of the system are joined by chemical bonds and demixing, needed for complete phase separation of the components, is strongly hindered and may lead to partial or complete decoupling from crystallization. The resulting product is then a metastable micro- or nanophase-separated system with arrested, local equilibria. In some cases, however, it is possible to change the copolymer composition during the crystallization or melting by chemical reactions, such as trans-esterification or -amidation. In this case, the chemical and physical equilibrium must both be considered and a phase separation of the copolymer into either crystalline homopolymers or block copolymers is possible. 

The development of SCF processes involves a consideration of the phase behavior of the system under supercritical conditions. The influence of pressure and temperature on phase behavior in such systems is complex. For example, it is possible to have multiple phases, such as liquid-liquid-vapor or solid-liquid-vapor equilibria, present in the system. In many cases, the operation of an SCF process under multiphase conditions may be undesirable and so phase behavior should first be investigated. The limiting case of equilibrium between two components (binary systems) provides a convenient starting point in the understanding of multicomponent phase behavior. 

The adsorption equilibria measurements of N2 and CO2 on activated carbon were performed using a standard static gravimetric method. Further details of these measurements are reported elsewhere." " The Sips isotherm extended to multi-component adsorption was adopted to fit the experimental equilibrium data (Table 9.2). This model has the Langmuirian form applied to non-uniform surfaces and it has been extensively used to model gas adsorption on micro-porous adsorbents and PSA systems. Optimal parameters were found for the adsorption isotherm model, by fitting simultaneously all the data at multiple temperatures. A global isotherm was obtained for each species as illustrated in Figure 9.15." ... 

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