Results 141 to 150 of about 404 (171)

Prediction of CO2 solubility in ionic liquids with QM and UNIQUAC models

Journal of Molecular Liquids, 2016
Abstract In recent years, ionic liquids shows their abilities in many processes, like enzymatic reactions, electrochemical applications, catalysis processes, or separation processes. In this work, CO2 solubility in Ionic liquids has been calculated based on two thermodynamic models, i.e., the UNIQUAC model and the quantum model, based on COSMO-RS ...
Amin Kamgar, Mohammad Reza Rahimpour
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Measurement and Prediction of the Solubility of Stearic Acid Polymorphs by the UNIQUAC Equation

The Canadian Journal of Chemical Engineering, 2004
AbstractThe solubility of stearic acid polymorphs B and C in methanol, 2‐butanone, decane and hexane was measured using a precise gravimetric method. Stearic acid is a molecule with 18 carbons that is highly nonideal in solutions and experimental data show strong deviations from the solubility prediction for ideal systems.
Mahmoud Mirmehrabi, Sohrab Rohani
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On the calculations of azeotropes from the NRTL and UNIQUAC models

Fluid Phase Equilibria, 1993
Abstract The local composition models of NRTL and UNIQUAC have been used in predicting of azeotropic data for binary and ternary liquid mixtures of various types. Activity coefficients have been calculated using the temperature dependent parameters of the models.
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Correlation of activity coefficients at infinite dilution with the wilson and uniquac equations

Journal de Chimie Physique, 1978
The problems involved in the determination of the parameters of thermodynamic models of liquid solutions were investigated. The Wilson equation and the UNIQUAC equation both at a single and at two parameters per binary system were focused. The adjustable constants of these models were evaluated on the basis of activity coefficients at infinite dilution
Paolo Alessi, Ireneo Kikic, Adriano Papo
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Excess enthalpy surfaces for alkanol-alkane mixtures by the uniquac model

Thermochimica Acta, 1995
Abstract Temperature and composition dependences of excess enthalpy surfaces and composition fluctuations were calculated using the uniquac model and the Kirkwood-Buff theory of statistical mechanics for seven alkanol-alkane mixtures. Surfaces of partial molar excess enthalpies and enthalpy of dilution were also calculated.
Y. Demirel, E.Z. Hamad
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CALCULATION OF VAPOR LIQUID EQUILIBRIUM AND EXCESS ENTHALPY WITH THE UNIQUAC EQUATION

Chemical Engineering Communications, 2007
The UNIQUAC equation was used for calculation of vapour liquid equilibrium (VLE) as well as excess enthalpy (hE). Four sets of binary interaction parameters were applied: first, parameters estimated only from VLE data, then parameters from hE data for both the original UNIQUAC equation and first the Anderson modification, and finally parameters ...
Åsa U. Burman, Krister H. U. Ström
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Calculations of thermodynamic derivative properties from the NRTL and UNIQUAC models

Thermochimica Acta, 1997
Abstract The local composition models NRTL and UNIQUAC with temperature-dependent parameters have been employed to calculate the surfaces of excess heat capacity, C E p , excess enthalpy, h E and thermodynamic factor, Γ for binary liquid mixtures. These thermodynamic properties represent the derivatives of the models with respect to temperature,
Demirel Y., Paksoy H.O.
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A new modification of the UNIQUAC equation including temperature dependent parameters

Fluid Phase Equilibria, 2001
Abstract The UNIQUAC equation was modified by introduction of a linear temperature dependence of the volume and surface area parameters, ri and qi. The slope of ri and qi functions were found to be the same for hydrocarbons and pyridine. The modified equation was used for prediction of vapor–liquid equilibria (VLE) in binary mixtures of hydrocarbons ...
Barbara Wiśniewska-Gocłowska, Stanisław K Malanowski   +1 more
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Calculation of infinite dilution activity coefficients by the NRTL and UNIQUAC models

The Canadian Journal of Chemical Engineering, 1990
AbstractInfinite dilution activity coefficients have been calculated for 42 binary systems using the NRTL and UNIQUAC models. Temperature dependent parameters of the models are used in the calculations. These parameters have been estimated by using excess Gibbs free energy and enthalpy of mixing data simultaneously.
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Calculation of enthalpy of mixing at infinite dilution by the nrtl and uniquac models

Thermochimica Acta, 1990
Abstract Enthalpies of mixing at infinite dilution have been calculated for 42 binary systems of liquid mixtures using the NRTL and UNIQUAC models. Temperature-dependent parameters of the models are used in the calculations. These parameters have been estimated by regressing excess Gibbs energy, gE, and enthalpy of mixing, hE, data simultaneously ...
openaire   +1 more source