UNIQUAC Associated-solution Research Articles

Excess enthalpies, and vapor-liquid equilibrium and surface properties of the highly non-ideal associated mixtures formed by an alcohol and propanal

Excess enthalpies, vapor-liquid equilibrium data and surface tensions of the highly non-ideal associated mixtures formed by methanol or ethanol and propanal have been measured in the temperature range of 288.15–318.15 K. These mixtures show negative deviations from ideality, including a negative azeotrope for the methanolpropanal system in the methanol-rich region. The values for the excess enthalpies are very exothermic and become less negative as temperature increases. Methanolpropanal mixtures exhibit minima of approximately −8.6 and −8.0 kJ mol −1, at a mole fraction close to 0.5 and 298.15 and 318.15 K, respectively. The ethanolpropanal system exhibits minima of approximately −7.2 and −5.0 kJ mol −1 at 298.15 and 318.15 K, respectively. The surface tension has been measured at 298.15 K. Values for the relative surface adsorption calculated from the surface tension and the chemical potentials indicate that the surface is significantly enriched in propanal for mixtures rich in methanol. The calculated values for the concentration-concentration correlation function are lower than those corresponding to an ideal mixture and exhibit a minimum in the middle of the concentration range. A complex composition dependence of the concentration profiles can be inferred. The Lattice-Fluid Associated Solution, the UNIQUAC Associated Solution and the Extended Real Associated Solution models have been used to describe the bulk properties of the alcoholpropanal mixtures.

Excess Molar Enthalpies of Ternary Mixtures for Propanone or Benzene + Aniline + 2-Methyl-1-propanol and of Binary Mixtures for Propanone or Aniline + 2-Methyl-1-propanol at 298.15 K

Experimental excess molar enthalpies for the ternary mixtures 2-methyl-1-propanol + aniline + propanone and 2-methyl-1-propanol + aniline + benzene and their constituent binary mixtures 2-methyl-1-propanol + aniline and 2-methyl-1-propanol + propanone at the temperature 298.15 K, measured by using an isothermal dilution calorimeter, are reported. The results have been analyzed using a polynomial equation and the UNIQUAC-associated solution model with binary and ternary parameters.

Isothermal vapour-liquid equilibrium for the ternary system ethanol + acetonitrile + acetone at 45°C

Vapour-liquid equilibrium data for the ternary ethanol + acetonitrile + acetone system at 45°C have been measured using a modified Boublik recirculating still. The experimental results are analysed by use of two activity coefficient models with binary parameters alone: uniquac associated-solution and extended uniquac. The former gives smaller deviations between experimental and calculated vapour composition and pressure values than does the latter.

Ternary liquid—liquid equilibria of (methanol + methylcyclohexane + propanols or butanols)

Liquid—liquid equilibria for (methanol + methylcyclohexane + 1-propanol or 2-propanol or 1-butanol or 2-butanol or iso-butanol or tert-butanol) have been measured at 298.15 K. The experimental results are compared with the predictions of the extended UNIQUAC and UNIQUAC associated-solution models having binary parameters and are correlated with the extended UNIQUAC model including additional ternary parameters.

Excess enthalpies of nonan-1-ol and undecan-1-ol with octane at high dilutions and at 298.15 K

Heats of mixing at high dilutions were determined for binary systems consisting of nonan-1-ol or undecan-1-ol and n-octane at 298.15 K. Partial molar heats of mixing at infinite dilution, giving approximate values of hydrogen bonding energies in alcohols, were determined by extrapolation of the experimental data to zero concentrations of the alcohols ( x 1 = 0). The results are correlated by means of polynomials, the UNIQUAC and the UNIQUAC associated-solution models. The ability of these equations to represent the thermodynamic functions of dilute mixtures of alkan-1-ols in n-alkanes at 298.15 K is discussed.

(Liquid + liquid) equilibria of {(acetonitrile + methylcyclohexane) + methanol or ethanol or propan-1-ol or propan-2-ol or butan-1-ol or butan-2-ol}

The (liquid + liquid) equilibrium results at 298.15 K have been obtained for {(acetonitrile + methylcyclohexane) + methanol or ethanol or propan-1-ol or propan-2-ol or butan-1-ol or butan-2-ol}. The ternary experimental results have been correlated with the extended UNIQUAC and UNIQUAC associated-solution models having binary parameters alone.

(Liquid + liquid) equilibria of (acetonitrile + 2-butanol or 2-methyl-2-propanol + cyclohexane or n-hexane or n-heptane)

The (liquid + liquid) equilibria of (acetonitrile + 2-butanol + cyclohexane or n-heptane) and of (acetonitrile + 2-methyl-2-propanol + cyclohexane or n-hexane or n-heptane) at 298.15 K have been measured. The ternary experimental results compare well with those predicted from the extended UNIQUAC and UNIQUAC associated-solution models with only binary parmeters.

Liquid-liquid equilibria for ternary mixtures containing two alcohols and one saturated hydrocarbon

Experimental tie-line data at 25 ° C are presented for the ternary systems methanol-(cyclo-hexane or n-heptane)-(1-propanol or 1-butanol or 2-butanol). The data were correlated by the extended UNIQUAC and UNIQUAC associated-solution models. The UNIQUAC associated-solution model gives better calculated results than the extended UNIQUAC model.

Liquid-liquid equilibria for the acetonitrile-2-propanol-saturated hydrocarbon and acetonitrile-isobutanol-saturated hydrocarbon systems

Tie-line data of (acetonitrile-2-propanol)-(cyclohexane or n-hexane or n-heptane) and of (acetonitrile-isobutanol)-(cyclohexane or n-hexane or n-heptane) at 25°C are presented. The experimental data for the ternary systems compare well with the values predicted by the extended UNIQUAC and UNIQUAC associated-solution models with binary parameters alone.

Isothermal vapour-liquid equilibria for binary and ternary mixtures formed by acetonitrile, isobutanol and benzene

Isothermal vapour-liquid equilibrium data were measured for the binary acetonitrile-isobutanol and ternary acetonitrile-isobutanol-benzene systems at 60° C by using a vapour-recirculating equilibrium still. The experimental data were correlated by the extended UNIQUAC and UNIQUAC associated-solution models. The UNIQUAC associated-solution model gives better predicted values for the ternary system.

Correlation and prediction of enthalpies of mixing for systems containing alcohols with UNIQUAC associated-solution theory

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCorrelation and prediction of enthalpies of mixing for systems containing alcohols with UNIQUAC associated-solution theoryVincenzo Brandani and Franco EvangelistaCite this: Ind. Eng. Chem. Res. 1987, 26, 12, 2423–2430Publication Date (Print):December 1, 1987Publication History Published online1 May 2002Published inissue 1 December 1987https://doi.org/10.1021/ie00072a006RIGHTS & PERMISSIONSArticle Views101Altmetric-Citations7LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (727 KB) Get e-Alerts Get e-Alerts

Prediction of thermodynamic equilibrium properties from mutual solubility data

The ability of four existing activity coefficient models to extrapolate mutual solubility data to completely miscible regions is studied. The UNIQUAC associated-solution, extended UNIQUAC, UNIQUAC and NRTL models are used to predict the behaviour of alcohol + saturated hydrocarbon systems. Only experimental mutual solubility data are used to obtain parameters for the four models. The results obtained using these models are compared. In addition, the ability of these models to calculate ternary liquid-liquid equilibria using only binary parameters is studied. The calculated results indicate that the UNIQUAC associated-solution model has the best overall performance.

ChemInform Abstract: The UNIQUAC Associated‐Solution Model. Excess Enthalpies of Mixtures of Hydrocarbons with Alcohol

Chemischer InformationsdienstVolume 17, Issue 15 Article ChemInform Abstract: The UNIQUAC Associated-Solution Model. Excess Enthalpies of Mixtures of Hydrocarbons with Alcohol I. NAGATA, I. NAGATASearch for more papers by this authorK. INAGUMA, K. INAGUMASearch for more papers by this author I. NAGATA, I. NAGATASearch for more papers by this authorK. INAGUMA, K. INAGUMASearch for more papers by this author First published: April 15, 1986 https://doi.org/10.1002/chin.198615074Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume17, Issue15April 15, 1986 RelatedInformation

The uniquac associated-solution theory: vapor-liquid equilibria of binary systems containing one associating and one inert or active component

Brandani, V. and Evangelista, F., 1984. The UNIQUAC associated-solution theory: vapor-liquid equilibria of binary systems containing one associating and one inert or active component. Fluid Phase Equilibria, 17: 281–302. This article critically reconsiders UNIQUAC associated-solution theory, clearly identifying the physical approximations of the model. Data for binary vapor-liquid equilibria are correlated with this theory using pure-liquid association parameters determined by the method described in a preceding paper. For alcoholic systems, fitting of only two (inert component) or three parameters (active component) to the experimental data gives good improvement over the results from the original UNIQUAC equation. However, in the case of amine systems with inert components, such as saturated hydrocarbons, the UNIQUAC associated-solution theory fails unless a solvation effect is considered empirically.

On the thermodynamics of associated solutions. III. vapor-liquid equilibria of binary and ternary systems with any number of associating components

Abstract Nath, A. and Bender, E., 1983. On the thermodynamics of associated solutions. III. Vapor-liquid equilibria of binary and ternary systems with any number of associating components. Fluid Phase Equilibria , 10: 43–56. UNIQUAC associated-solution theory as described in Part II of this series is developed for binary and ternary systems containing any number of associating components. The new equations are used to reduce binary vapor-liquid equilibrium data. The theory reproduces the experimental data quite well and is able to predict ternary vapor-liquid equilibria. The results are compared with those of the UNIQUAC and Wilson equations.