Thermodynamics of mixtures containing the CO and OH groups. I. Estimation of the DISQUAC interchange coefficients for 1-alkanol + n-alkanone systems

1997 ◽  
Vol 75 (10) ◽  
pp. 1412-1423 ◽  
Author(s):  
Juan Antonio González

1-Alkanol + n-alkanone mixtures are treated in terms of the DISQUAC group contribution model, reporting the interaction parameters for hydroxyl–carbonyl contacts. The quasichemical interchange coefficients are independent of the compounds in the mixture; the dispersive interchange coefficients depend on the intramolecular environment of the hydroxyl and (or) carbonyl groups. Mixtures of a given 1-alkanol with isomeric ketones are characterized by the same first dispersive interaction parameter, which is constant from 2-pentanone. This type of system, when including an alcohol up to 1-pentanol, needs different dispersive enthalpic parameters depending on the symmetry of the ketone. In this case, such parameters are constant from 2-pentanone or 3-pentanone. A detailed comparison is presented between DISQUAC results and data available in the literature on vapour–liquid equilibria, VLE (including azeotropic data), molar Gibbs energies, GE, molar excess enthalpies, HE, solid–liquid equilibria, SLE, natural logarithms of activity coefficients, In [Formula: see text] and partial molar excess enthalpies at infinite dilution,[Formula: see text]. For 54 systems, the mean relative standard deviation in pressure is 0.018; for 61 systems, this magnitude in the case of the HE is 0.059. It is noteworthy that the model yields good predictions over a very wide range of temperature for VLE and SLE. HE is also reasonably well represented at different temperatures. Larger discrepancies are encountered, as usual, for partial molar quantities at infinite dilution. Keywords: liquids, mixtures, thermodynamic properties, group contributions.

2010 ◽  
Vol 295 (2) ◽  
pp. 194-200 ◽  
Author(s):  
Vladimír Dohnal ◽  
Pavel Vrbka ◽  
Karel Řehák ◽  
Alexander Böhme ◽  
Albrecht Paschke

1997 ◽  
Vol 75 (10) ◽  
pp. 1424-1433 ◽  
Author(s):  
Juan Antonio González ◽  
I. García De La Fuente ◽  
J.C. Cobos

Thermodynamic properties: vapour–liquid equilibria, VLE, or excess enthalpies, HE, for a set of 21 ternary mixtures of the type 1-alkanol + n-alkanone + organic solvent are studied in the framework of the DISQUAC group contribution model. This treatment is extended to the binaries involved. The DISQUAC analysis is developed on the basis of binary interactions only, that is, ternary interactions are neglected. Most of the interchange coefficients needed are available in the literature. The average relative standard deviations are 0.026 for pressure in the VLE (12 systems) and 0.098 in the HE (9 systems). The discrepancies observed are briefly discussed. Keywords: 1-alkanols, n-alkanones, group contribution, liquids, ternary systems, thermodyamics.


2002 ◽  
Vol 80 (5) ◽  
pp. 476-482 ◽  
Author(s):  
Urszula Domanska ◽  
Juan Antonio Gonzalez

Equilibrium temperatures for solid–liquid transitions of mixtures formed by sulfolane and ethanenitrile, propanenitrile, butanenitrile, or pentanenitrile were measured by a dynamic method. The solid–liquid equilibria phase diagrams show positive deviations from Raoult's law, except for the system with ethanenitrile, which is nearly ideal. The sulfolane–nitrile and sulfolane–1-alkyne interactions have been characterized in terms of the DISQUAC group contribution model. DISQUAC properly represents a complete set of thermodynamic properties: solid–liquid equilibria, molar excess enthalpies, and natural logarithms of activity coefficients. DISQUAC predictions are valid over a wide temperature range.Key words: solid–liquid equilibria, thermodynamics, mixtures, interactions.


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