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1.
The excess molar volumes, V mE, viscosity deviations, Δη, and excess Gibbs energies of activation, ΔG *E, of viscous flow have been investigated from density and viscosity measurements for two ternary mixtures, 1-butanol + triethylamine + cyclohexane and 1-pentanol + triethylamine + cyclohexane, and corresponding binaries at 303.15 K and atmospheric pressure over the entire range of composition. The empirical equations due to Redlich-Kister, Kohler, Rastogi et al., Jacob-Fitzner, Tsao-Smith, Lark et al., Heric-Brewer, and Singh et al. have been employed to correlate V mE, Δη and ΔG *E of the ternary mixtures with their corresponding binary parameters. The results are discussed in terms of the molecular interactions between the components of the mixture. Further, the Extended Real Associated Solution, ERAS, model has been applied to V mE for the present binary and ternary mixtures, and the results are compared with experimental data.  相似文献   

2.
Densities and viscosities of the binary mixtures of m-cresol with 1,2-dichloroethane, 1,1,1-trichloroethane, 1,1,2,2-tetrachloroethane and tetrachloroethylene were measured at 303.15, 313.15 and 323.15 K. The measured results are used to compute the excess volumes (VE), deviations in viscosity (Δη) and excess Gibbs energy for activation of flow (ΔGE). The excess volumes, deviations in viscosity, and Gibbs energies for activation of flow are fitted to a polynomial-type equation suggested by Scharlin et al. [J. Chem. Thermodyn. 34, 927 (2002)] and are discussed in general terms.  相似文献   

3.
Summary. Density (ρ) and viscosity (η) values of the binary mixtures of DMP + 1-pentanol, 1-butanol, and 1-propanol over the entire range of mole fraction at 298.15 and 303.15 K were measured in atmospheric pressure. The excess molar volume (V E), viscosity deviations (Δη), and excess Gibbs energy of activation for viscous flow (G*E) were calculated from the experimental measurements. These results were fitted to Redlich–Kister polynomial equation to estimate the binary interaction parameters. The viscosity data were correlated with equations of McAllister. The calculated functions have been used to explain the intermolecular interaction between the mixing components.  相似文献   

4.
Ultrasound velocity (u), density (ρ) and viscosity (η) measurements of benzaldehyde + ethylbenzene mixtures have been carried out at 303.15, 308.15, and 313.15 K. These values have been used to calculate the excess molar volume (V E), deviation in viscosity (δη), and deviation in isentropic compressibility (δβs), deviations in ultrasound velocity (δu), excess free volume (δV f), excess intermolecular free length (δL f) and excess Gibbs free energy of activation of viscous flow (δG E). McAllister’s three body interaction model is used for correlating kinematic viscosity of binary mixtures. The excess values were correlated using the Redlich-Kister polynomial equation to obtain their coefficients and standard deviations. The thermophysical properties under the study were fit to the Jouyban-Acree model. The observed variation of these parameters helps in understanding the nature of interactions in these mixtures. Further, theoretical values of the ultrasound speed were evaluated using theories and empirical relations.  相似文献   

5.
The excess molar volume (V E), viscosity deviations (Δη) and Gibbs excess energy of activation for viscous flow (G∗E) have been investigated from density (ρ) and viscosity (η) measurements of eight binary mixtures of 1,3-dioxolane with methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, t-butanol, and i-amyl alcohol over the entire range of mole fractions at 303.15 K. The viscosity data have been correlated with the Grunberg and Nissan equation. Furthermore, excess isentropic compressibilities (KSE) have been calculated from ultrasonic speed measurements of these binary mixtures at 303.15 K. The deviations have been fitted by a Redlich–Kister equation and the results are discussed in terms of molecular interactions and structural effects. The excess properties are found to be either negative or positive depending on the molecular interactions and the nature of the liquid mixtures. The systems studied exhibit very strong cross association through hydrogen bonding.  相似文献   

6.
The excess molar volume VE, shear viscosity deviation Δη and excess Gibbs energy of activation ΔGE of viscous flow have been investigated by using density (ρ) and shear viscosity (η) measurements for isobutyric acid + water (IBA+W) mixtures over the entire range of mole fractions at five different temperatures, both near and close to the critical temperature (2.055K ≤ (TTc)≤ 13.055K). The results were also fitted with the Redlich–Kister equation. This system exhibited very large negative values of VE and very large positive values of Δη due to increased hydrogen bonding interactions and correlation length between unlike molecules in the critical region and to very large differences between the molar volumes of the pure components at low temperatures. The activation parameters ΔH and ΔS have been also calculated and show that the critical region has an important effect on the volumetric properties.  相似文献   

7.
Densities (ρ), viscosities (η) and speeds of sound (u) of the ternary mixture (1-heptanol + tetrachloroethylene + methylcyclohexane) and the corresponding binary mixtures (1-heptanol + tetrachloroethylene), (1-heptanol + methylcyclohexane) and (tetrachloroethylene + methylcyclohexane) at 298.15 K were measured over the whole composition range. The data obtained are used to calculate the excess molar volumes (V E), excess isobaric thermal expansivities (α E), viscosity deviations (Δη), excess Gibbs energies of activation of viscous flow (ΔG *E) and excess isentropic compressibilities (κ S E) of the binary and ternary mixtures. The data from the binary systems were fitted by the Redlich–Kister equation whereas the best correlation method for the ternary system was found using the Nagata equation. Viscosities, speeds of sound and isentropic compressibilities of the binary and ternary mixtures have been correlated by means of several empirical and semi-empirical equations. The best correlation method for viscosities of binary systems is found using the Iulan et al. equation and for the ternary system using the Heric and McAllister equations. The best correlation method for the speeds of sound and isentropic compressibilities of the binary system (1-heptanol + methylcyclohexane) is found using IMR (Van Deal ideal mixing relation) and for the binary system (tetrachloroethylene + methylcyclohexane) it is found using the NR (Nomoto relation) and for the binary system (1-heptanol + tetrachloroethylene) and the ternary system (1-heptanol + trichloroethylene + methylcyclohexane) it is obtained from the FLT (Jacobson free length theory).  相似文献   

8.
Densities, viscosities and speeds of sound of binary mixtures of ethyl benzoate with cyclohexane, n-hexane, heptane and octane have been measured over the entire range of composition at (303.15, 308.15 and 313.15) K and at atmospheric pressure. From these experimental values, excess molar volume (V E), deviation in viscosity (Δη) and deviation in isentropic compressibility (ΔK s) have been calculated. The viscosities of binary mixtures were calculated theoretically from the pure component data by using various empirical and semi-empirical relations and the results compared with the experimental findings.  相似文献   

9.
《Fluid Phase Equilibria》2004,218(2):247-260
Density (ρ) and viscosity (η) values of the binary mixtures of phenetole+1-pentanol, + 1-hexanol, + 1-heptanol, + 1-octanol, + 1-nonanol, and + 1-decanol over the entire range of mole fraction at 293.15, 298.15, 308.15, and 318.15 K have been measured at atmospheric pressure. The excess molar volume (VE), viscosity deviations (Δη), and excess Gibbs energy of activation (G*E) have been calculated from the experimental measurements. These results were fitted to Redlich and Kister polynomial equation to estimate the binary interaction parameters. The viscosity data were correlated with equations of Grunberg and Nissan, Hind et al., Frenkel, and McAllister. While the excess molar volumes of phenetole+1-pentanol, + 1-hexanol are positive, the remaining binary mixtures are negative. The viscosity deviations and excess Gibbs energy of activation are negative for all investigated systems. As the chain length of 1-alkanols increases, both viscosity deviations and excess molar volume values decrease while excess Gibbs energy of activation value increase. The temperature has no effect on excess molar volume, slight effect on excess Gibbs energy of activation, and significant effect on viscosity deviations. The calculated functions have been used to explain the intermolecular interaction between the mixing components.  相似文献   

10.
The viscosity deviation (Δη), the excess molar volume (V E) and the ultrasonic speed (u) have been investigated from viscosity (η) and density (ρ ) measurements of binary liquid mixtures of 1,2-dimethyoxyethane with methanol, ethanol, propan-1-ol, butan-1-ol, pentan-1-ol, hexan-1-ol or octan-1-ol over the entire range of composition at 298.15 K. The excess volumes are negative over the entire range of composition for all of the mixtures with the exception of hexan-1-ol and octan-1-ol. The excess isentropic compressibilities (K S E) and viscosity deviations are negative for all of the mixtures. The magnitudes of the negative values of V E decrease with the number of carbon atoms of the alkan-1-ol. The trend of increasing K S E values with the chain length of the alkanol is similar to that observed in the case of V E. Graphs of V E, Δ η, K S E, Δ u, L f E and Z E against composition are presented as a basis for a qualitative discussion of the results.  相似文献   

11.
    
Excess molar volumes (V m E ), viscosity deviations (Δlnη) and excess energies of activation for viscous flow (ΔG*E) are reported for non-electrolyte mixtures of 1,2-dimethoxyethane (monoglyme) and dichloromethane, trichloromethane, and tetrachloromethane at 298·15 K and at atmospheric pressure over the whole mole fraction range. The Prigogine-Flory-Patterson (PFP) model has been used to calculateV m E , and the results are compared with experimental data. The Bloomfield and Dewan model has been used to calculate viscosity coefficients, which are compared with experimental data for three mixtures. These results have been analysed in terms of dipole-dipole interactions between 1,2-dimethoxyethane and chloroalkanes. The magnitude of the strength of interaction decreases with the dipole character of the molecule.  相似文献   

12.
The excess values of molar volume (V E), viscosity deviation (Δη), deviation in isentropic compressibility (ΔKS ), excess molar refraction (ΔR) and excess Gibbs energy of activation (ΔG*E ) of viscous flow have been investigated from the experimentally measured densities, viscosities, sound speeds and refractive indices for three binary mixtures of acetophenone?+?n-amyl alcohol, acetophenone?+?dichloromethane and n-amyl alcohol?+?dichloromethane and their corresponding ternary mixtures at 298.15?K over the entire composition range. The calculated quantities are further fitted to the Redlich–Kister equation to estimate the binary fitting parameters and standard deviations from the regression lines. The excess or deviation properties were found to be either negative or positive depending on the molecular interactions and the nature of liquid mixtures and have been discussed in terms of molecular interactions and structural changes.  相似文献   

13.
The densities (ρ) and viscosities (η) for the ternary liquid mixtures of water + N,N-dimethylformamide + monoalkanols, have been measured as a function of the composition at 298.15, 308.15, and 318.15 K. From the experimental measurements excess molar volumes (V E), Viscosity deviation (Δη), and synergy index (I s) have been evaluated. The speeds of sound have been also measured and excess isentropic compressibilities (K sE) are calculated al 298.15 K. The results are discussed and interpreted in terms of molecular package and specific interaction predominated by hydrogen bonding, been investigated.  相似文献   

14.
The densities ρ, speeds of sound u, and viscosities η, of pure 1-butanol, 1,2-dichloroethane, 1,1,1-trichloroethane, 1,1,2,2-tetrachloroethane, trichloroethylene, and tetrachloroethylene and those of their binary mixtures have been measured at 298.15 K and atmospheric pressure over the entire range of compositions. Excess molar volumes V E, viscosity deviations Δη, deviation in compressibilities Δκs and excess Gibbs energy of activation G*E, were obtained from the experimental results and those were fitted to Redlich–Kister's type function in terms of mole fractions. Viscosities, speeds of sound and isentropic compressibilities of the binary mixtures have been correlated by means of several empirical and semi-empirical equations. The experimental data are analysed to discuss the nature and strength of intermolecular interactions in these mixtures.  相似文献   

15.
Densities, viscosities and ultrasonic speeds of sound for binary mixtures of 1,2-dimethoxyethane (DME) with benzene, toluene, chlorobenzene, benzyl chloride, benzaldehyde, nitrobenzene, and aniline are reported over the entire composition range at ambient pressure and temperature (i.e., T=298.15 K and p=1.01×105 Pa). These experimental data were utilized to derive the excess molar volumes (VmEV_{\mathrm{m}}^{\mathrm{E}}), excess viscosities (η E), and various acoustic parameters including the deviation in isentropic compressibility (Δκ S ), internal pressure (π I), and excess enthalpy (H E). From the excess molar volumes (VmEV_{\mathrm{m}}^{\mathrm{E}}), the excess partial molar volumes ([`(V)]m,1E\overline{V}_{\mathrm{m},1}^{\mathrm{E}} and [`(V)]m,2E\overline{V}_{\mathrm{m},2}^{\mathrm{E}}) and excess partial molar volumes at infinite dilution ([`(V)]m,10,E\overline{V}_{\mathrm{m},1}^{0,\mathrm{E}} and [`(V)]m,20,E\overline{V}_{\mathrm{m},2}^{0,\mathrm{E}}) were derived and discussed for each liquid component in the mixtures. The excess/deviation properties were found to be either negative or positive, depending on the molecular interactions and the nature of the liquid mixtures.  相似文献   

16.

Densities and viscosities of binary mixtures of dimethyl sulfoxide (DMSO) with tert-butyl alcohol, butyl acetate, butanone, and butyl amine were determined over the entire range of mole fractions at temperatures of 298.15, 308.15, and 318.15 K. At each temperature, the excess molar volume (V E), viscosity deviations (Δη), and Gibbs excess free energy of activation for viscous flow (ΔG *E) have been investigated from these measured density (ρ) and viscosity (η) values. The experimental viscosity data were correlated by means of the equations of Grunberg-Nissan, Tamura and Kurata, and Hind et al. The deviations have been fitted to a Redlich-Kister equation, and the results are discussed in terms of molecular interactions and structural effects.

  相似文献   

17.
The density (ρ), viscosity (η) and ultrasonic velocity (u) of three mixtures consisting of 2- pyrrolidone with 1,3-propanediol (PD) and water and also of PD and water have been measured as a function of mole fraction at 308.15 K. The experimentally collected data has been used to calculate the excess molar volume (VE), deviation in viscosity (Δη), deviation in ultrasonic velocity (Δu), isentropic compressibility (κs), deviation in isentropic compressibility (Δκs) and excess Gibbs free energy of activation (ΔG*E). The Redlich–Kister polynomial equation has been used to fit the derived parameters. The variation in excessive thermodynamic properties as a consequence of possible molecular interactions is discussed.  相似文献   

18.

Abstract  

Experimental densities ρ, viscosities η, and refractive indices n D of the ternary mixtures consisting of 2-methyltetrahydrofuran + chlorobenzene + cyclopentanone and constituted binary mixtures were measured at T = 298.15 K for the liquid region and at ambient pressure for the whole composition range. Excess molar volumes V\textm\textEV_{\text{m}}^{\text{E}}, deviations in the viscosity Δη, and deviations in the refractive index Δn D from the mole fraction average for the mixtures were derived from the experimental data. The excess partial molar volumes V\textm,i\textEV_{{\text{m}},i}^{\text{E}} were also calculated. The binary and ternary data of V\textm\textEV_{\text{m}}^{\text{E}}, Δη, and Δn D were correlated as a function of the mole fraction by using the Redlich–Kister and the Cibulka equations, respectively. McAllister’s three-body interaction model is used for correlating the kinematic viscosity of binary mixtures with the mole fraction.  相似文献   

19.
Densities and refractive indices have been measured for binary mixtures of 1-propyronitrile-3-hexylimidazolium bromide + ethanol in the temperature range 293.15–323.15 K. From the experimental data the excess molar volume V E, refractive index deviation Δn D, and the coefficient of thermal expansion α were calculated and fitted to fifth- and third-order Redlich–Kister type equations, respectively. Using the measured densities, the apparent molar volumes (V ϕ ), limiting apparent molar volumes (Vf0V_{\phi}^{0}) and limiting apparent molar expansivities (Ef 0E_{\phi} ^{0}) were also determined and the details are discussed.  相似文献   

20.
Densities (d 12) and viscosities (η12) have been measured for 2-methoxyethanol (ME) with tetrahydrofuran (THF) binary liquid mixtures over the whole composition range at various temperatures ranging from 291.15 to 308.15 K. The experimental data were used to test some empirical equations of the type: y 12=y 12(t) and y 12=y 12(X 1) [where: y 12d 12 or η12]. From all these data, the excess molar volumes (V 12 E), the excess viscosities (η12 E) and excess Gibbs activation energies (ΔG *) of viscous flow were calculated. These structural parameters as a function of concentration suggest the formation of 3ME⋅THF and 2ME⋅THF types of intermolecular complexes. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

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