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1.
《Fluid Phase Equilibria》2003,211(1):61-73
Densities, speeds of sound and heats of mixing for the ternary system hexane+1,3-dioxolane+1-butanol have been measured at atmospheric pressure at the temperatures of 298.15 and 313.15 K. Excess molar volumes, excess isentropic compressibilities, and excess molar enthalpies have been calculated from experimental data and fitted by Cibulka equation. Excess molar properties were analysed in terms of molecular interactions as well as structural and packing effects.  相似文献   

2.
Densities and speeds of sound for the ternary system 1-butanol+1,4-dioxane+cyclohexane have been measured at the temperatures of 298.15 and 313.15 K. Excess molar volumes and excess isentropic compressibilities have been calculated from experimental data and fitted by the Redlich-Kister equation for ternary mixtures. The ERAS model has been used to calculate excess molar volumes of the ternary mixture from parameters obtained from the constituent binary mixtures.  相似文献   

3.
《Thermochimica Acta》1987,109(2):377-382
Excess volumes have been determined over the entire composition range for benzyl alcohol + N,N-dimethylmethanesulfinamide, + N,N-dimethylbenzenesulfinamide and + dimethyl sulfoxide at 303.06 and 323.21 K. The excess molar volumes are negative for all three systems, corresponding to the tendency of sulfinyl compounds to form hydrogen-bonded complexes with benzyl alcohol.  相似文献   

4.
Excess molar volumes and excess refractive indexes of the n-hexanol + ethanenitrile + dichloromethane system and the three corresponding binary mixtures have been determined at 25°C, by measuring densities and refractive indexes. Different expressions exist in the literature to predict these excess properties from binary data. The empirical correlation of Cibulka is shown to be the best in this system. An estimation of excess molar volumes is also evaluated using a modified Heller equation, which depends on the refractive indexes of the mixtures. Comparison of the predictions by different methods with the experimental values of the physical properties has been made.  相似文献   

5.
Excess molar volume, excess viscosity, excess molar enthalpy, and excess molar Gibbs free energy were calculated from the experimental density, viscosity, heat of mixing and vapor-liquid equilbrium data, respectively, for the chloroform + tetrahydrofuran system at 30°C over the complete molar fraction range. The results have been satisfactorily interpreted by assuming the existence of three species A, AB, and B in mutual equilibrium and that these species mix ideally. Values are given for the equilibrium constant and heat of formation of AB.  相似文献   

6.
Excess enthalpies of sixteen binary mixtures between one each of methyl methylthiomethyl sulfoxide (MMTSO) and dimethyl sulfoxide (DMSO) and one of ketone {CH3CO(CH2)nCH3, n=0 to 6 and CH3COC6H5} have been determined at 298.15 K. All the mixtures showed positive excess enthalpies over the whole range of mole fractions. Excess enthalpies of ketone+MMTSO or DMSO increased with increasing the number of methylene radicals in the methyl alkyl ketone molecules. Excess enthalpies of MMTSO+ketone are smaller than those of DMSO+ketone for the same ketone mixtures. The limiting excess partial molar enthalpies of the ketone, H 1 E,∞, in all the mixtures with MMTSO were smaller than those of DMSO. Linear relationships were obtained between limiting excess partial molar enthalpies and the number of methylene groups except 2-propanone.  相似文献   

7.
Excess molar enthalpies HE and excess molar volumes VE have been measured at 298.15 K and 0.1 MPa for the ternary mixture tetrahydrofuran (THF) + propan-1-ol (PrOH) + n-heptane including the three binary mixtures using flow calorimetry and a vibrating tube densitometer, respectively.

Molar excess Gibbs energies GE have been measured at 298.15 K using a static VLE apparatus equipped with a chromatographic sampling technique for the vapor phase as well as for the liquid phase. Experimental results have been compared with predictions of the ERAS model.  相似文献   


8.
Excess molar volumes VmE as function of mole fraction x for methylcyclohexane + benzene, + methylbenzene, + 1,4-dioxane, and + tetrahydrofuran are reported at 303.15 K. The excess molar volumes are positive and indicate the presence of weak interactions.  相似文献   

9.
Excess molar volumes, change of refractive indexes, and deviation of dynamic viscosity of the 2-methoxyethanol + acetonitrile, 2-methoxyethanol + 1,2-dichloroethane, and acetonitrile + 1,2-dichloroethane binary systems and the excess molar volumes of 2-methoxyethanol + acetonitrile + 1,2-dichloroethane ternary system have been determined at 25°C and at atmospheric pressure, by measuring densities, refractive indexes, and viscosities over the entire range of composition. These derived data of binary and ternary mixtures were fitted to Redlich–Kister and Cibulka equations, respectively. An estimation of excess volumes is also evaluated using a modified Heller equation, which depends on the refractive indexes of the mixture. A comparison of the predictions by different methods with the experimental values of the physical properties has been made.  相似文献   

10.
Experimental excess molar enthalpies and excess molar volumes of the ternary system x1MTBE+x21-propanol+(1-x1-x2) hexane and the involved binary mixtures have been determined at 298.15 K and atmospheric pressure. Excess molar enthalpies were measured using a standard Calvet microcalorimeter, and excess molar volumes were determined from the densities of the pure liquids and mixtures, using a DMA 4500 Anton Paar densimeter. The UNIFAC group contribution model (in the versions of Larsen et al., and Gmehling et al.) has been employed to estimate excess enthalpies values. Several empirical expressions for estimating ternary properties from experimental binary results were applied.  相似文献   

11.
Excess molar volumes, at the temperature 25°C and atmospheric pressure over the whole composition range, are reported for the following binary mixtures: methyl ethanoate + (n-octane, n-decane); methyl ethanoate + 1-chlorooctane; 1-chlorooctane + (n-heptane, n-octane, n-nonane, n-decane); and for the ternary mixtures methyl ethanoate + 1-chlorooctane + (n-heptane, n-octane, n-nonane, n-decane). The values of excess molar volumes were calculated from density and composition results. The excess volumes were utilized to test the multiproperty group-contribution model of Nitta et al. using parameter sets available in the literature. Experimental results from ternary mixtures have also been compared to predictions from several empirical and semiempirical models, which utilize, exclusively, results from binary mixtures.  相似文献   

12.
The density and speed of sound of the ternary mixture (diethyl carbonate + p-xylene + octane) have been measured at atmospheric pressure and in the temperature range T = (288.15 to 308.15) K. Besides, surface tension has been also determined for the same mixture at T = 298.15 K. The experimental measurements have allowed the calculation of the corresponding derived properties: excess molar volumes, excess isentropic compressibilities, and surface tension deviations. Excess properties have been correlated using Nagata and Tamura equation and correlation for the surface tension deviation has been done with the Cibulka equation. Good accuracy has been obtained. Based on the variations of the derived properties values with composition, a qualitative discussion about the intermolecular interactions was drawn.  相似文献   

13.
Densities of glycerol + N,N-Dimethylformamide (DMF) and glycerol + water mixtures have been measured over the full range of compositions at 25 and 35°C. Excess molar volumes and excess partial molar volumes, of each system have been calculated. All mixtures show negative values of the excess molar volume due to increased interactions between unlike molecules.  相似文献   

14.
Siddiq, M.A. and Lucas, K., 1984. Excess enthalpy of the system chloroform + carbon tetrachloride and a thermodynamic evaluation of its state dependence. Fluid Phase Equilibria, 16: 87–98.Excess molar enthalpies of the system chloroform + carbon tetrachloride have been measured over the entire concentration range at 283.15, 293.15, 303.15, 313.15 and 323.15 K using an isothermal high-pressure flow calorimeter. The effect of pressure was also studied by measuring excess enthalpies at 15 and 30 MPa along the 293.15, 313.15 and 323.15 K isotherms. The temperature dependence of the excess enthalpies was used to calculate vapour-liquid equilibria as a function of temperature. The results are excellent. Further evaluation of the temperature and pressure dependences of the excess enthalpy is discussed.  相似文献   

15.
《Fluid Phase Equilibria》2004,216(2):293-299
Excess molar enthalpies, measured at 298.15 K in a flow microcalorimeter, are reported for the ternary mixtures (tetrahydrofuran + diisopropyl ether + n-heptane) and (tetrahydrofuran + 2-methyltetrahydrofuran + n-heptane). Smooth representations of the results are described and used to construct constant excess molar enthalpy contours on Roozeboom diagrams. The latter are compared with diagrams obtained when the model of Liebermann and Fried is used to estimate the excess enthalpies of the ternary mixtures from the physical properties of the components and their binary mixtures.  相似文献   

16.
Mixing properties of the ternary mixture acetone + methanol + n-octane have been determined experimentally under standard conditions. Sound velocity, densities, and refractive indexes were measured as functions of composition. Excess molar volumes, changes of refractive indexes, and changes of isentropic compressibilities on mixing were computed from the experimental data. The Peng–Robinson and Soave–Redlich–Kwong equations of state were applied with three different mixing rules to correlate binary excess volumes and then to predict the excess magnitudes in ternary mixtures. Reliable representations of the experimental data were obtained.  相似文献   

17.
Summary In this paper we present excess molar volumes and excess molar enthalpies of binary and ternary mixtures containing propyl propanoate, hexane and cyclohexane as components at 298.15 K. Excess molar volumes were calculated from the density of the pure liquids and mixtures. The density was measured using an Anton Paar DMA 60/602 vibrating-tube densimeter. Excess molar enthalpies were obtained using a Calvet microcalorimeter  相似文献   

18.
Excess molar enthalpies, measured at 25°C in a flow microcalorimeter, are reported for the three ternary systems [ethanol + methyl tert-butyl ether + (n-hexane or 2,3-dimethylbutane, or cyclohexane)]. Smoothing equations were fitted to the results and used to construct constant excess enthalpy contours for each of the systems.  相似文献   

19.
Excess molar volumes and excess viscosities of the propan-2-ol + tetrahydrofuran+ 1-chlorobutane system have been determined at 25°C from measurements ofdensities and viscosities. Various expressions are proposed in the literature tocalculate these excess properties from binary data. The empirical correlation ofCibulka is shown to be the best in this system for excess volume, viscosity, andenergy of activation for viscous flow. An application to excess molar volumeshas been made by using Flory's theory. For viscosities, we applied the equations ofGrunberg and Nissan, Katti and Chaudhri, Bloomfield and Dewan, and Wu—andfinally the GC-UNIMOD model.  相似文献   

20.
The densities of propan-2-ol + pentan-1-ol, + hexan-1-ol, + heptan-1-ol, + octan-1-ol + nonan-1-ol and speeds of sound in propan-2-ol + pentan-1-ol, + heptan-1-ol, + nonan-1-ol have been measured over the whole composition range at 298.15 K. Excess molar functions determined from the experimental data have been plotted as functions of composition. The excess molar volumes have been interpreted on the basis of the Symmetrical Extended Real Associated Solution Model (S-ERAS).  相似文献   

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