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1.
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   

2.
The kinematic viscosity ν for (ethane-1,2-diol  +  1,2-dimethoxyethane  +  water) was measured at 14 different ternary compositions covering the whole miscibility field, and at 19 temperatures in the range 263.15 ⩽T /  K 353.15. The experimental values were fitted using empirical equations of the type ν = ν (T) and ν = ν (xi), respectively, in order to provide reliable models to account for the behaviour of the system. The excess kinematic viscosity νEhas been determined and interpreted in terms of the type and nature of the interactions among the components of the mixture. Using the experimental ν data, the thermodynamic properties ( ΔG * , ΔH * ,ΔS *  ) of the viscous flow have been obtained from the Eyring’s approach and standard thermodynamic equations. Furthermore, excess mixing functions, such asΔG * E , have been determined, and found to evidence the existence of quite strong specific interactions among the components, probably due to the formation of hydrogen bonds and dipolar networks. However, all the calculated excess mixing properties suggest the absence of stable three-component adducts.  相似文献   

3.
4.
The vapor pressures of (ethanol + glycerol) and (water + glycerol) binary mixtures were measured by means of two static devices at temperatures between (273 and 353 (or 363)) K. The data were correlated with the Antoine equation. From these data, excess Gibbs free energy functions (GE) were calculated for several constant temperatures and fitted to a fourth-order Redlich–Kister equation using the Barker method. The (ethanol + glycerol) binary system exhibits positive deviations in GE where for the (water + glycerol) mixture, the GE is negative for all temperatures investigated over the whole composition. Additionally, the NRTL, UNIQUAC and Modified UNIFAC (Do) models have been used for the correlation or prediction of the total pressure.  相似文献   

5.
The vapour pressures of liquid (3-diethylaminopropylamine (3-DEPA) + n-heptane) mixtures were measured by a static method between T = (303.15 and 343.15) K at 10 K intervals. The molar excess enthalpies HE at T = 303.15 K were measured for the systems {3-DEPA + CnH2n+2 (n = 6, 7, 12)}. The molar excess Gibbs free energies GE were obtained with Barker’s method and fitted to the Redlich–Kister equation. The Wilson equation was also used. Deviations between experimental and predicted GE and HE, by using group contribution UNIFAC (Gmehling version) model, were evaluated.  相似文献   

6.
《Fluid Phase Equilibria》2006,239(2):146-155
This work reports the measured density, ρ, and viscosity, η, values of liquid mixtures of tetrahydrofuran (1) + 1-chlorobutane (2) + 2-butanol (3) at temperatures of 283.15, 298.15 and 313.15 K over a range of mole fractions and atmospheric pressure. Excess molar volume, VE, viscosity deviations, Δη, and excess free energies of activation of viscous flow, ΔG*E, have been calculated from experimental data and fitted to Cibulka, Singh et al. and Nagata and Sakura equations. The results were analyzed in terms of the molecular interaction between the components of the mixtures. Excess molar volumes and viscosity deviations were predicted from binary contributions using geometrical solution models, Tsao and Smith; Jacob and Fitzner; Kholer; Rastogi et al.; Radojkovic et al. Finally, experimental results are compared with those obtained by applying group-contribution method proposed by Wu.  相似文献   

7.
The excess molar volumes VmE at T=298.15 have been determined in the whole composition domain for (2-methoxyethanol + tetrahydrofuran + cyclohexane) and for the parent binary mixtures. Data on VmE are also reported for (2-ethoxyethanol + cyclohexane). All binaries showed positive VmE values, small for (methoxyethanol + tetrahydrofuran) and large for the other ones. The ternary VmE surface is always positive and exhibits a smooth trend with a maximum corresponding to the binary (2-methoxyethanol + cyclohexane). The capabilities of various models of either predicting or reproducing the ternary data have been compared. The behaviour of VmE and of the excess apparent molar volume of the components is discussed in both binary and ternary mixtures. The results suggest that hydrogen bonding decreases with alcohol dilution and increases with the tetrahydrofuran content in the ternary solutions.  相似文献   

8.
《Fluid Phase Equilibria》2006,239(2):178-182
Isothermal vapour–liquid equilibrium data have been measured for the ternary system (di-isopropyl ether + isobutanol + benzene) and two of the binary systems involved (di-isopropyl ether + isobutanol) and (isobutanol + benzene) at 313.15 K. A static technique consisting of an isothermal total pressure cell was used for the measurements. Data reduction by Barker's method provides correlations for GE using the Margules equation for the binary systems and the Wohl expansion for the ternary system. Wilson, NRTL and UNIQUAC models have been applied successfully to both the binary and the ternary systems.  相似文献   

9.
The vapour pressures of liquid {3-diethylaminopropylamine (3-DEPA) + cyclohexane} were measured by a static method between T = (273.15 and 363.15) K at 10 K intervals. The excess molar volumes VE at 298.15 K and excess molar enthalpies HE at 303.15 K were also measured. The molar excess Gibbs free energies GE were obtained with Barker’s method and fitted to the Redlich–Kister equation. The Wilson equation was also used. Deviations between experimental and predicted GE and HE, by using DISQUAC model, were evaluated  相似文献   

10.
The measurement of excess enthalpies, HE, at T=298.15 K and densities at temperatures between 283.15 K and 313.15 K are reported for the (2-methoxyethanol + 1,4-dioxane) and (1,2-dimethoxyethane + benzene) systems. The values of HE and the excess volumes, VE, are positive, and the temperature dependence of VE is quite small for (2-methoxyethanol + 1,4-dioxane). The (1,2-dimethoxyethane + benzene) system shows a negative HE and sigmoid curves in VE, which change sign from positive to negative with an increase in 1,2-dimethoxyethane. The temperature dependence of VE for this system is negative.  相似文献   

11.
Experimental (vapour + liquid) equilibrium results for the binary systems, (methanol + water) at the local atmospheric pressure of 95.3 kPa and at sub-atmospheric pressures of (15.19, 29.38, 42.66, 56.03, and 67.38) kPa, (water + glycerol) system at pressures (14.19, 29.38, 41.54, 54.72, 63.84, and 95.3) kPa and the (methanol + glycerol) system at pressures (32.02 and 45.3) kPa were obtained over the entire composition range using a Sweitoslwasky-type ebulliometer. The relationship of the liquid composition (x1) as a function of temperature (T) was found to be well represented by the Wilson model. Computed vapour phase mole fractions, activity coefficients and the measured values along with optimum Wilson parameters are presented.  相似文献   

12.
The vapour pressures of (sec-butylamine + water), (cyclohexylamine + water) binary mixtures, and of pure sec-butylamine and cyclohexylamine components were measured by means of two static devices at temperatures between 293 (or 273) K and 363 K. The data were correlated with the Antoine equation. From these data, excess Gibbs functions (GE) were calculated for several constant temperatures and fitted to a fourth-order Redlich–Kister equation using the Barker’s method. The (cyclohexylamine + water) system shows positive azeotropic behaviour for all investigated temperatures. The two binary mixtures exhibit positive deviations in GE for all investigated temperatures over the whole composition range.  相似文献   

13.
Density ρ, viscosity η, and refractive index nD, values for (tetradecane + benzene, + toluene, + chlorobenzene, + bromobenzene, + anisole) binary mixtures over the entire range of mole fraction have been measured at temperatures (298.15, 303.15, and 308.15) K at atmospheric pressure. The speed of sound u has been measured at T = 298.15 K only. Using these data, excess molar volume VE, deviations in viscosity Δη, Lorentz–Lorenz molar refraction ΔR, speed of sound Δu, and isentropic compressibility Δks have been calculated. These results have been fitted to the Redlich and Kister polynomial equation to estimate the binary interaction parameters and standard deviations. Excess molar volumes have exhibited both positive and negative trends in many mixtures, depending upon the nature of the second component of the mixture. For the (tetradecane + chlorobenzene) binary mixture, an incipient inversion has been observed. Calculated thermodynamic quantities have been discussed in terms of intermolecular interactions between mixing components.  相似文献   

14.
The paper reports experimental px data for the ternary system (ethyl 1,1-dimethylethyl ether + 1-hexene + toluene) at T = 313.15 K. The ether, synthesized from ethanol of biological origin, increases the interest of this compound as an additive for gasolines. An isothermal total pressure cell was used for the measurements. Data reduction by Barker’s method provides correlations for GE, using Wilson, NRTL, UNIQUAC models and the Wohl expansion for the ternary system and the calculation of the vapor phase composition. Good results are obtained for the correlation by all the models.  相似文献   

15.
16.
In this paper, densities of (linalool  +  methanol, or ethanol, or n -propanol, or n -butanol) are determined at T =  303.15 K using a vibrating-tube densimeter. The excess molar volumes VmEvalues are negative in all the systems over the entire composition range and correlated by the Redlich–Kister equation. The effects of chain length of alkanols onVmE have been discussed.  相似文献   

17.
Total vapour pressures, measured at the temperature 313.15 K, are reported for the ternary mixture (N,N-dimethylacetamide + ethanol + water), and for binary constituent (N,N-dimethylacetamide + ethanol). The present results are also compared with previously obtained data for (amide + ethanol) binary mixtures, where amide = N-methylformamide, N,N-dimethylformamide, N-methylacetamide, 2-pyrrolidinone, and N-methylpyrrolidinone. We found that excess Gibbs free energy of mixing for binary (amide + ethanol) mixtures varies roughly linearly with the molar volume of amide.  相似文献   

18.
Density, ρ, speed of sound, u, and refractive index, nD, at 298.15 K and atmospheric pressure have been measured over the entire composition range for (toluene + methyl acetate + butyl acetate) and (toluene + methyl acetate + methyl heptanoate) systems. Excess molar volumes, VE, isentropic compressibility, κs, isentropic compressibility deviations, Δκs, and changes of refractive index on mixing, ΔnD, for the above systems, have been calculated from experimental data and fitted to Cibulka, Singh et al., and Nagata and Sakura equations, standard deviations from the regression lines are shown. Geometrical solution models, Tsao and Smith, Kholer, Jacob and Fitzner, Rastogi et al. were also applied to predict ternary properties from binary contributions.  相似文献   

19.
The vapour pressures of (2-amino-2-methyl-1-propanol (AMP) + water), (N-benzylethanolamine + water), or (3-dimethylamino-1-propanol + water) binary mixtures, and of pure AMP and 3-dimethylamino-1-propanol components were measured by means of two static devices at temperatures between 283 K and 363 K. The data were correlated with the Antoine equation. From these data, excess Gibbs functions (GE) were calculated for several constant temperatures and fitted to a fourth-order Redlich–Kister equation using the Barker’s method. The {2-amino-2-methyl-1-propanol (AMP) + water} binary mixture exhibits negative deviations in GE (at T < 353.15 K) and a sinusoidal shape for GE for the higher temperatures over the whole composition range. For the aqueous N-benzylethanolamine solution, a S shape is observed for the GE for all investigated temperatures over the whole composition range. The (3-dimethylamino-1-propanol + water) binary mixture exhibits negative deviations in GE (at T < 293.15 K), positive deviations in GE (for 293.15 K < T < 353.15 K) and a sinusoidal shape for GE for the higher temperatures over the whole composition range.  相似文献   

20.
Density and viscosity measurements for binary mixtures of (1,1,2,2-tetrabromoethane + 1-pentanol, or + 1-hexanol, or + 1-heptanol, or + 1-octanol, or + 1-decanol) at T = (293.15 and 303.15) K, have been conducted at atmospheric pressure. The excess molar volumes VE, have been calculated from the experimental measurements, and the results were fitted to Redlich–Kister equation. The viscosity data were correlated with the model of Grunberg and Nissan, and McAllister four-body model. The excess molar volumes of (1,1,2,2-tetrabromoethane + 1-pentanol, or + 1-haxanol, or + 1-heptanol, or + 1-octanol) had a sigmoidal shape and the values varied from negative to positive with the increase in the molar fraction of 1,1,2,2-tetrabromoethane. The remaining binary mixture of (1,1,2,2-tetrabromoethane + 1-decanol) was positive over the entire composition range. The effects of the 1-alkanol chain length as well as the temperature on the excess molar volume have been studied. The results have been qualitatively used to explain the molecular interaction between the components of these mixtures.  相似文献   

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