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1.
The densities and speeds of sound of (ethanol + isooctane), (ethanol + toluene), and (ethanol + isooctane + toluene) were measured at four temperatures over the range (298.15 to 328.15) K, and the respective values of excess volumes and adiabatic compressibility κS were calculated. The and κS values for the binary systems were fitted to the Redlich–Kister equation. The respective ternary data together with corresponding binary data were then fitted to the modified Redlich–Kister equation considering various numbers of ternary constants. It was found that even for the systems containing self-associating alcohol, only one ternary parameter is sufficient to describe well the ternary system.  相似文献   

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The densities of pyridine, 2-picoline, 3-picoline, and 4-picoline were measured at elevated pressures (0.1 to 40) MPa at four temperatures over the range (298.15 to 328.15) K with a high-pressure apparatus. The high-pressure density data were fitted to the Tait equation and the isothermal compressibility were calculated with a novel computation procedure with the aid of this equation.  相似文献   

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Densities were measured for the liquid octane and 1-chlorohexane, and for nine of their mixtures at four temperatures between 298.15 K and 328.15 K and at pressures up to 40 MPa. An apparatus for density measurements of liquids and liquid mixtures whose main part is a high-pressure vibrating-tube densimeter working in a static mode was used for the measurement. The density data were fitted to the Tait equation and the isothermal compressibilities were calculated with the aid of this equation. Excess molar volumes were also computed from the densities and fitted to the Redlich–Kister equation.  相似文献   

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《Fluid Phase Equilibria》2006,248(1):24-28
(Liquid–liquid) equilibrium data for the ternary systems [water + formic acid or acetic acid or propionic acid + cumene (2-phenylpropane, isopropylbenzene)] at 298.15 K are reported. Complete phase diagrams were obtained by determining solubility and the tie-line data. The reliability of the experimental tie-lines was determined through the Othmer–Tobias plots. Distribution coefficients and separation factors were evaluated for the immiscibility region. The tie-line data were compared with the results predicted by the UNIFAC method.  相似文献   

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The vapour pressures of binary (cyclopentanone + 1-chlorobutane, +1,3-dichloropropane, and +1,4-dichlorobutane) mixtures, were measured at the temperatures of (298.15, 308.15, and 318.15) K. The vapour pressures vs. liquid phase composition data have been used to calculate the excess molar Gibbs free energies GE of the investigated systems, using Barker’s method. Redlich–Kister, Wilson and NRTL equations, taking into account the vapor phase imperfection in terms of the second virial coefficient, have represented the GE values. No significant difference between GE values obtained with these equations has been observed.  相似文献   

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Excess molar volumes of (α,α,α-trifluorotoluene + ethanol), (2,2,2-trifluoroethanol + ethanol), (diisopropyl ether + ethanol), and (diisopropyl ether + 2,2,2-trifluoroethanol), and (α,α,α-trifluorotoluene + 2,2,2-trifluoroethanol + ethanol), and (diisopropyl ether + 2,2,2-trifluoroethanol + ethanol) were measured with a vibrating-tube densimeter at the temperature 298.15 K and the pressure 101 kPa.The values of the mixing volumes of the ternary systems were predicted in terms of empirical equations using binary solution data alone. The extent of chemical associations among the molecules forming the mixtures is discussed.  相似文献   

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Values of the density and speed of sound were measured for the ternary system (methyl tert-butyl ether + methylbenzene + butan-1-ol) within the temperature range (298.15 to 328.15) K at atmospheric pressure by a vibrating-tube densimeter DSA 5000. Two binary sub-systems were studied and published previously while the binary sub-system (methyl tert-butyl ether + butan-1-ol) is a new study in this work. Excess molar volume, adiabatic compressibility, and isobaric thermal expansivity were calculated from the experimental values of density and speed of sound. The excess quantities were correlated using the Redlich–Kister equation. The experimental excess molar volumes were analyzed by means of both the Extended Real Associated Solution (ERAS) model and the Peng–Robinson equation of state. The novelty of this work is the qualitative prediction of ternary excess molar volumes for the system containing auto-associative compound and two compounds that can hetero-associate. The combination of the ERAS model and Peng–Robinson equation of state could help to qualitatively estimate the real behavior of the studied systems because the experimental results lie between these two predictions.  相似文献   

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In this paper, (liquid + liquid) equilibrium (LLE) data for the ternary systems (cyclohexane, or cyclooctane, or methylcyclohexane + ethylbenzene + 1-ethyl-3-methylimidazolium ethylsulfate) have been determined experimentally at T = 298.15 K and atmospheric pressure. The solubility curves and the tie-line compositions of the conjugate phases were obtained by means of density. The degree of consistency of the tie-lines was tested using the Othmer–Tobias equation, and the Non-Random Two-Liquid (NRTL) and the Universal Quasi-Chemical (UNIQUAC) models were used to correlate the phase equilibrium in the systems. Selectivity and solute distribution ratio were evaluated for the immiscible region.  相似文献   

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(Liquid + liquid) equilibrium (LLE) data were measured experimentally at T = (298.15 or 303.15) K and atmospheric pressure for the (benzene + cyclohexane + dimethyl sulfone (DMSO)) system. The Othmer–Tobias equation was applied to verify the reliability of the data. Based on the data, the selectivity of DMSO was estimated and compared with that of ionic liquids. The highest selectivity coefficient of DMSO can reach beyond 14, which means it is able to compete with some ionic liquids and it would be a good extractant to separate benzene from cyclohexane. At the same time, the NRTL model was used to correlate the data and the results show that the model agrees on the experimental data very well.  相似文献   

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Isothermal vapor–liquid equilibrium data at 333.15 K are reported for the ternary system di-isopropyl ether (DIPE) + n-propyl alcohol + toluene and the binary subsystems DIPE + n-propyl alcohol, DIPE + toluene and n-propyl alcohol + toluene by using headspace gas chromatography. The excess molar volumes at 298.15 K for the same binary and ternary systems were also determined by directly measured densities. The experimental binary and ternary vapor–liquid equilibrium data were correlated with different GE models and the excess molar volumes were correlated with the Redlich–Kister equation for the binary systems and the Cibulka equation for the ternary system, respectively.  相似文献   

17.
The vapour pressures of binary (cyclohexanone + 1-chlorobutane, + 1,1,1-trichloroethane) mixtures were measured at the temperatures of (298.15, 308.15, and 318.15) K. The vapour pressures vs. liquid phase composition data have been used to calculate the excess molar Gibbs free energies GE of the investigated systems, using Barker’s method. Redlich–Kister, Wilson, UNIQUAC, and NRTL equations, taking into account the vapour phase imperfection in terms of the 2-nd virial coefficient, have represented the GE values. No significant difference between GE values obtained with these equations has been observed.  相似文献   

18.
The aim of this paper is to report experimental densities, excess molar enthalpies and refractive indexes of the ternary system (propyl propanoate + hexane + toluene) and of the corresponding binary mixtures (propyl propanoate + toluene) and (hexane + toluene) at the temperature 298.15 K and atmospheric pressure, over the whole composition range. Also, the excess molar volumes and the changes in the refractive index on mixing have been calculated from the measured data for all mixtures.  相似文献   

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Liquid-liquid equilibrium (LLE) data for the ternary systems of (water-formic acid-diethyl maleate), (water-acetic acid-diethyl maleate), (water-propionic acid-diethyl maleate), (water-butyric acid-diethyl maleate), and (water-valeric acid-diethyl maleate) were investigated at 298.15 K and atmospheric pressure. Complete phase diagrams were obtained by determining solubility and the tie-line data. The tie-line data were compared with the results predicted by the UNIFAC and the modified UNIFAC (Dortmund) methods and correlated by means of UNIQUAC model. The reliability of the experimental tie-line data was confirmed by using the Othmer-Tobias correlation. Distribution coefficients and selectivity were evaluated for the immiscibility region.  相似文献   

20.
Densities and viscosities of binary liquid mixtures of (1-hexanol  + n -hexane, or cyclohexane, or benzene) have been measured at a number of mole fractions at T =  (303, 313, and 323) K. The excess molar volume VmEand apparent molar volume Vφhave been calculated from the density data. TheVmE anddVmE / dT for the system, (1-hexanol  + n -hexane) have been found negative, while those for the systems, (1-hexanol  +  cyclohexane) and (1-hexanol  +  benzene), were found to be positive. Excess viscosities ηEcalculated from viscosity data, have been found to be negative over the whole composition range at the temperatures studied for all the three systems. Volumetric and viscometric behaviours indicate that dispersion is the major force of interaction between the components in (1-hexanol  +  cyclohexane, or benzene), while inclusion of hydrocarbon chains into the interstices of polymolecular ring structures of alcohol formed by hydrogen bonding has been assumed to play a significant role apart from dispersion in the system (1-hexanol  + n -hexane). Thermodynamic parameters of activation for viscous flow have been calculated from the viscosity data at different temperatures and a possible explanation suggested.  相似文献   

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