UNIQUAC Associated-solution Model Research Articles

Calorimetric study of the mutual effect in binary and pseudobinary mixtures of some aliphatic alcohols and some cyclic ethers

Excess molar enthalpies, for (methanol+ethanol+oxane) and (methanol+ethanol+1, 4-dioxane) mixtures at 298.15K and atmospheric pressure were measured experimentally. The experimental results were correlated with a polynomial equation to estimate the coefficients. The pseudobinary excess molar enthalpies for all systems under investigation are found to be positive over the entire range of compositions. The experimental results were explained according to the UNIQUAC associated solution model. The ternary excess molar enthalpies, Hm,123E for {methanol (1)+ethanol (2)+1, 4-dioxane (3)} system are higher than that of {methanol (1)+ethanol (2)+oxane (3)} system. Also the ternary excess molar enthalpies Hm,123E in the different methanol compositions are in the order: 25% methanol>that 50% methanol>75% methanol.

Excess Molar Enthalpies of Ternary Mixtures of Ethanol + 1-Propanol + Tetrahydropyran or 1,4-Dioxane at 298.15 K

Excess molar enthalpies for the (ethanol + 1-propanol + tetrahydropyran) and (ethanol + 1-propanol + 1,4-dioxane) ternary mixtures and their binaries (ethanol + tetrahydropyran) have been measured by a flow microcalorimeter at 298.15 K and ambient pressure. The experimental results are correlated with a polynomial equation. The results have been compared with those calculated from a UNIQUAC associated-solution model. This model considers the self-association of like alcohols, cross-association of unlike alcohols, and solvation between alcohols and tetrahydropyran or 1,4-dioxane. The model with the association constants, solvation constants, and binary information alone could satisfactorily represent the ternary excess molar enthalpies.

Excess molar enthalpies of ternary mixtures of (methanol, ethanol + 2-propanol + 1,4-dioxane) at T=298.15 K

Ternary excess molar enthalpies for the { x 1CH 3OH + x 2 i-C 3H 7OH + (1− x 1− x 2) c-C 4H 8O 2} and { x 1C 2H 5OH + x 2 i-C 3H 7OH + (1− x 1− x 2) c-C 4H 8O 2} mixtures have been measured by a flow microcalorimeter at T=298.15 K and ambient pressure. The experimental results are correlated with a polynomial equation and used to construct constant excess enthalpy contours. Furthermore, the results have been compared with those calculated from a UNIQUAC associated-solution model. This model considers the self-association of like alcohols, multicross-association of unlike alcohols, and solvation between alcohols and 1,4-dioxane. The model with the association constants, solvation constants, and binary information alone predict the ternary excess molar enthalpies satisfactorily.

Excess molar enthalpies of (methanol + 1-propanol) + oxane or 1,4-dioxane mixtures at the temperature 298.15 K

Experimental excess molar enthalpies H m E at the temperature 298.15 K and atmospheric pressure in a flow microcalorimeter are reported for the ternary mixtures: { x 1CH 3OH+ x 2C 2H 5OH+(1− x 1− x 2)C 5H 10O} and { x 1CH 3OH+ x 2C 2H 5OH+(1− x 1− x 2)C 4H 8O 2}. The results have been correlated by means of a polynomial equation and used to construct constant excess enthalpy contours. Further, the results have been compared with those calculated from a UNIQUAC associated-solution model taking into consideration the molecular association of like alcohols, solvation between unlike alcohols and alcohols with oxane (tetrahydropyran) or 1,4-dioxane using only binary information.

Ternary excess molar enthalpies for the mixtures of methanol and ethanol with tetrahydropyran or 1,4-dioxane at 298.15 K

Ternary excess molar enthalpies, H m E, at 298.15 K and atmospheric pressure measured by using a flow microcalorimeter are reported for the (methanol+ethanol+tetrahydropyran) and (methanol+ethanol+1,4-dioxane) mixtures. The pseudobinary excess molar enthalpies for all the systems are found to be positive over the entire range of compositions. The experimental results are correlated with a polynomial equation to estimate the coefficients and standard errors. The results have been compared with those calculated from a UNIQUAC associated solution model in terms of the self-association of alcohols as well as solvation between unlike alcohols and alcohols with tetrahydropyran or 1,4-dioxane. The association constants, solvation constants and optimally fitted binary parameters obtained solely from the pertinent binary correlation predict the ternary excess molar enthalpies with an excellent accuracy.

An associated-solution model for hydrogen-bonding molecules and multicomponent liquid–liquid equilibria for methanol, methyl tert-butyl ether, tert-amyl methyl ether, toluene, and 2,2,4-trimethylpentane mixtures

A new UNIQUAC associated-solution model taking into account association of hydrogen-bonding molecules and solvation between unlike molecules with allowance for a non-polar interaction was presented to predict the ternary and quaternary liquid–liquid equilibria (LLE) for the mixtures of associating molecule acetonitrile, aniline, and methanol with non-associating components. The 17 ternary systems were represented successfully using only binary parameters. The model was further used to represent the experimental tie-line data for quaternary mixture of the methanol+2,2,4-trimethylpentane (TMP)+methyl tert-butyl ether (MTBE)+ tert-amyl methyl ether (TAME) system and those of constituent three ternary mixtures of the methanol+TMP+MTBE, methanol+TMP+TAME and methanol+TMP+toluene systems measured at the temperature 298.15 K and ambient pressure. Good agreement between the experimental results and those calculated by the associated-solution model was obtained. Additionally, the results were compared with those calculated by extended and modified UNIQUAC models that assume no chemical equilibria between associating molecules.

Excess Molar Enthalpies for Ethanol + 2-Propanol + Methyl tert-Butyl Ether and 1-Propanol + 2-Propanol + Methyl tert-Butyl Ether at the Temperature of 298.15 K

Ternary excess molar enthalpies for the ethanol + 2-propanol + methyl tert-butyl ether (MTBE) and 1-propanol + 2-propanol + MTBE systems have been measured by a flow microcalorimeter at 298.15 K and ambient pressure. The pseudobinary excess molar enthalpies are positive over the whole range of composition. The ternary experimental results are correlated with a polynomial equation. The results have been compared with those calculated from a UNIQUAC associated-solution model taking into account the self-association of alcohols as well as the solvation between unlike alcohols and alcohols with MTBE using only binary parameters.

Excess molar enthalpies of ternary mixtures formed by methanol and methyl tert-butyl ether with ethanol or 1-propanol at 298.15 K

Ternary excess molar enthalpies for (methanol+ethanol+methyl tert-butyl ether (MTBE)) and (methanol+1-propanol+MTBE) mixtures have been measured with a flow microcalorimeter at T=298.15 K and atmospheric pressure. Constant contours for the ternary experimental results were calculated by a polynomial equation. Further, the results have been compared with those calculated from a UNIQUAC associated-solution model taking into account the molecular self- and cross-association of two alcohols and the solvation among the alcohols and MTBE. The results predicted by using binary parameters obtained from the corresponding experimental binary results alone are in good agreement with the experimental values.

Ternary excess molar enthalpies of alcohols with methyl t-butyl ether at T = 298.15 K

Ternary excess molar enthalpies HEm at 298.15 K and atmospheric pressure measured in a flow microcalorimeter are reported for the methanol+2-propanol+methyl t-butyl ether (MTBE) and ethanol+1-propanol+MTBE systems. The ternary results have been correlated by means of a polynomial equation and used to construct constant excess enthalpy contours. Furthermore, the results have been compared with those calculated from a UNIQUAC associated-solution model taking into account molecular association of alcohols and solvation between unlike alcohols and alcohols with MTBE using only binary information.

Ternary Excess Molar Enthalpies for Methanol or Ethanol + 1-Propanol + 2-Propanol at the Temperature 298.15 K

The excess molar enthalpies for the ternary systems methanol + 1-propanol + 2-propanol and ethanol + 1-propanol + 2-propanol have been measured at 298.15 K and atmospheric pressure using a flow microcalorimeter. The ternary experimental results are correlated with a polynomial equation and compared with those predicted by the UNIQUAC associated-solution model having self-association and cross-association constants and binary parameters alone.

Excess molar enthalpies HE of ternary mixtures of (methanol+ethanol+1-propanol or 2-propanol) at 298.15 K

The excess molar enthalpies H E of the liquid mixtures of (methanol+ethanol+1-propanol) and (methanol+ethanol+2-propanol) have been measured at 298.15 K and atmospheric pressure using a flow microcalorimeter. The experimental H E are used to test the suitability of an extended version of the UNIQUAC associated-solution model with binary parameters alone. The model requires solvation equilibrium constants for alcohols not to be the geometric mean of the self-association constants to provide better results.

96/042 Indoor air-quality control by a fuzzy-reasoning machine in naturally ventilated buildings

Nagata, I., Fukushima, Y. and Miyazaki, K., 1992. Vapour-liquid equilibrium in the quaternary system methanol-2-propanol-acetonitrile-benzene at 55 ° C. Fluid Phase Equilibria,71: 17-27.The isothermal vapour-liquid equilibrium for the quaternary methanol-2-propanol-acetonitrile-benzene system have been determined using a modified Boublik vapour-recirculating still at 55 ° C. The experimental results are in good agreement with those calculated by the UNIQUAC associated-solution model based on binary information alone.

96/04249 Energy paper's direction OK, but speed has to be increased

Nagata, I., Fukushima, Y. and Miyazaki, K., 1992. Vapour-liquid equilibrium in the quaternary system methanol-2-propanol-acetonitrile-benzene at 55 ° C. Fluid Phase Equilibria,71: 17-27.The isothermal vapour-liquid equilibrium for the quaternary methanol-2-propanol-acetonitrile-benzene system have been determined using a modified Boublik vapour-recirculating still at 55 ° C. The experimental results are in good agreement with those calculated by the UNIQUAC associated-solution model based on binary information alone.

Ternary Vapor−Liquid Equilibria of Ethanol + Acetone + Benzene at 318.15 K

Isothermal vapor−liquid equilibria of ethanol + acetone + benzene were measured using a modified Boublik still at 318.15 K. The experimental results are compared with those calculated using the UNIQUAC associated-solution model with binary parameters, and a good agreement between the experimental and calculated values is obtained.

Ternary Vapor−Liquid Equilibria of 2-Propanol + Cyclohexane + Toluene at 318.15 K

Isothermal vapor−liquid equilibria of 2-propanol + cyclohexane + toluene were measured using a modified Boublik still at 318.15 K. The experimental results are compared with those calculated using the UNIQUAC associated-solution model with only binary parameters.

Excess Molar Enthalpies of Ternary Systems Butan-1-ol or Butan-2-ol + Aniline + Propanone and of Binary Systems Butan-1-ol or Butan-2-ol + Propanone at the Temperature 298.15 K

The excess molar enthalpies at the temperature 298.15 K for ternary systems butan-1-ol + aniline + propanone and butan-2-ol + aniline + propanone and their constituent binary systems butan-1-ol + propanone and butan-2-ol + propanone, measured with an isothermal dilution calorimeter, are reported. The experimental results have been analyzed and compared with a polynomial equation and the UNIQUAC-associated solution model with binary and ternary additional parameters.

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.

Application of the uniquac associated-solution model to alkanoic acid + alkanol and ifalkanol + hydrocarbon mixtures

The UNIQUAC associated-solution model has been applied to reproduce vapour-liquid equilibria and excess molar enthalpies for binary mixtures containing one alkanoic acid and one alkanol and then to predict ternary excess molar enthalpies for acetic acid + methanol + tetrachloromethane. Furthermore, the model has been modified to include additional parameters in order to obtain a better correlation of vapour-liquid equilibria of strongly non-ideal mixtures involving at least one alkanol. The calculated results agree well with the experimental values for many systems studied.

Thermodynamics of associated solutions. Correlation of ternary excess molar enthalpies for aniline + alkanol + benzene or acetone mixtures using the UNIQUAC associated-solution model

Ternary excess molar enthalpies are reported for 1-propanol + aniline + acetone at 25°C. The UNIQUAC associated-solution model with ternary parameters is used to correlate ternary excess molar enthalpies for aniline + alkanol + benzene or acetone mixtures. The model gives appreciably smaller deviations between the calculated and experimental results than those obtained using polynomial equations.

Excess molar enthalpies of binary and ternary mixtures containing aniline and 2-butanol

Excess molar enthalpies for (aniline + 2-butanol) and (aniline + 2-butanol + benzene) at 298.15 K, measured using an isothermal dilution calorimeter, are reported. The experimental binary and ternary results have been correlated by use of Redlich-Klister like polynomial equation and compared with those calculated from the uniquac associated-solution model having only binary parameters.