首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Densities,ρ, ultrasonic speeds, u, viscosities,η, and refractive indices, n, of pure benzene, benzyl alcohol (BA), benzonitrile (BN), benzoyl chloride (BC), chlorobenzene (CB) and their thirty six binary mixtures, with benzene as common component, were measured at 303.15 K over the entire mole fraction range. From these experimental data the values of deviations in ultrasonic speed, △u, isentropic compressibility, △ks,excess acoustic impedance, ZE, deviation in viscosity, Dh, and excess Gibbs free energy of activation of viscous flow, G*E, and partial molar isentropic compressibility, Kφ,20 of BA, BN, BC and CB in benzene were computed. The variation of these derived functions with composition of the mixtures suggested the increased cohesion (molecular order) in the solution and that interaction (A-B)>(A-A) or (B-B).Moreover, theoretical prediction of ultrasonic speed, viscosity and refractive index of all the four binary mixtures was made on the basis of empirical and semi-empirical relations by using the experimental values of the pure components. Comparison of theoretical results with the experimental values was made in order to assess the suitability of these relations in reproducing the experimental values of u, η and n. Also, molecular radii of pure liquids and the average molecular radii of binary mixtures were evaluated using the corresponding refractive indices of pure liquids and binary mixtures. The average molecular radii of binary mixtures were found to be additive with respect to mole fraction of the pure component.  相似文献   

2.

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   

3.
Densities, viscosities, speed of sound, and IR spectroscopy of binary mixtures of tert-butyl acetate (TBA) with benzene, methylbenzene, and ethylbenzene have been measured over the entire range of composition, at (298.15 and 308.15) K and at atmospheric pressure. From the experimental values of density, viscosity, speed of sound, and IR spectroscopy; excess molar volumes VE, deviations in viscosity Δη, deviations in isentropic compressibility Δκs and stretching frequency ν have been calculated. The excess molar volumes and deviations in isentropic compressibility are positive for the binaries studied over the whole composition, while deviations in viscosities are negative for the binary mixtures. The excess molar volumes, deviations in viscosity, and deviations in isentropic compressibility have been fitted to the Redlich–Kister polynomial equation. The Jouyban–Acree model is used to correlate the experimental values of density, viscosity, and speed of sound.  相似文献   

4.
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   

5.
Excess molar volumes (V E), viscosities, refractive index, and Gibbs energies were evaluated for binary biodiesel + benzene and toluene mixtures at 298.15 and 303.15 K. The excess molar volumes V E were determined from density, while the excess Gibbs free energy of activation G*E was calculated from viscosity deviation Δη. The excess molar volume (V E), viscosity deviation (Δη), and excess Gibbs energy of activation (G*E) were fitted to the Redlich-Kister polynomial equation to derive binary coefficients and estimate the standard deviations between the experimental data and calculation results. All mixtures showed positive V E values obviously caused by increased physical interactions between biodiesel and the organic solvents.  相似文献   

6.
Densities (ρ) at 293.15, 298.15, 303.15, 308.15, and 313.15 K, viscosities (η) at 293.15, 298.15, and 303.15 K and refractive indexes (n) at 298.15 K of binary mixtures of ethyl tert-butyl ether (1) + 2-butoxyethanol (2), are reported. The excess molar volumes (V E) and the viscosities, and refractive index deviations (Δln η and Δn) were calculated from these experimental data. The results are discussed in terms of intermolecular interactions.  相似文献   

7.
Density and refractive index have been measured for the binary mixture of dimethyl sulphoxide (DMSO) with propanoic acid and n-butyric acid at three temperatures, 293, 303 and 313 K, over the entire composition range. Excess parameters such as excess molar volume (V E) and molar refraction deviation (ΔR m) have been calculated from the measured density and refractive index to study the molecular association between the component molecules. The V E and ΔR m values of these mixtures were fitted to the Redlich–Kister polynomial equation. Both excess parameters were plotted against the mole fraction of DMSO over the whole composition range. The values of V E and ΔR m have been found to be negative for both mixtures over the entire composition range, which suggests the presence of strong intermolecular interaction. The experimental refractive data of these mixtures were also used to test the validity of the empirical relations for the refractive index.  相似文献   

8.
Densities (ρ) and viscosities (η) of ternary mixtures of 2-methylbutan-2-ol (1) + trichloroethylene (2) + acetonitrile (3) and the related binary mixtures of {2-methylbutan-2-ol (1) + trichloroethylene (2)}, {2-methylbutan-2-ol (1) + acetonitrile (3)}, and {trichloroethylene (2) + acetonitrile (3)} have been measured over the whole composition range at 298.15 K and at ambient pressure (81.5 kPa). Excess molar volumes $ V_{\text{m}}^{\text{E}} $ , viscosity deviations Δη, and excess Gibbs energies of activation ΔG *E were derived from the experimental data. The binary and ternary data of $ V_{\text{m}}^{\text{E}} $ , Δη, and ΔG *E for the binary and ternary mixtures were correlated as functions of the mole fraction by using the Redlich–Kister and the Cibulka equations. Kinematic viscosities of the binary mixtures were correlated by means of several semi-empirical equations to determine the fitting parameters and the SDs. The experimental results are analyzed to discuss the nature and strength of intermolecular interactions in these mixtures.  相似文献   

9.
Densities (ρ) at different temperatures from 303.15 to 318.15 K, speeds of sound (u) and viscosities (η) at 303.15 K were measured for the binary mixtures of cyclohexanol with 2-chlorotoluene, 3-chlorotoluene and 4-chlorotoluene over the entire range of composition. The excess volumes (VE) for the mixtures have been computed from the experimental density data. Further, the deviation in isentropic compressibilities (Δκs) and deviation in viscosities (Δη) for the binary mixtures have been calculated from the speed of sound and viscosity data, respectively. The VE values and Δκs values were positive and Δη data were negative for all the mixtures over the whole range of composition at the measured temperatures. The calculated excess functions VE, Δκs and Δη were fitted to Redlich–Kister equation. The excess functions have been discussed in terms of molecular interactions between component molecules of the binary mixtures.  相似文献   

10.
The viscosities at T = (293.15, 298.15 and 303.15) K and ultrasonic speeds at T = 298.15 K in the binary liquid mixtures of 2-methoxyethanol with diethylene glycol, triethylene glycol and tetraethylene glycol have been measured over the entire mixture compositions. From the experimental data, deviations in the viscosity (Δη), ultrasonic speed (Δu), and excess energies of activation for viscous flow (ΔG* E ) have been calculated. The viscosity data were correlated with equations of Hind et al., Grunberg and Nissan, Frenkel, and McAllister. The results are discussed in terms of intermolecular interactions and structure of studied binary mixtures.  相似文献   

11.
Densities and viscosities for binary mixtures of N-methyl-2-pyrrolidinone with cyclohexane, benzene, and toluene were determined at different temperatures and atmospheric pressure. The measurements were carried out over the whole range of composition, using a vibrating-tube density meter and Ubbelohde viscometer. Density, viscosity were used to compute the excess mole volumes, VE, viscosity deviations, Δη and the excess energies of activation, ΔG1E. Results have been fitted to Redlich–Kister equation to derive the coefficients and estimate the standard error values. A discussion on these quantities in terms of molecular interactions is reported. The experimental data of molar volumes are regressed by the Peng–Robinson equation with different alpha function. The mean root mean square deviations between experimental and calculated values for different binary mixtures are no more than 3.5%.  相似文献   

12.
Densities and viscosities have been determined for binary mixtures of isopropyl acetate or isobutyl acetate with o-xylene, m-xylene, p-xylene and ethyl benzene at (303.15 and 313.15) K for the entire composition range. The excess molar volumes and deviations in viscosity have been calculated from the experimental values. The variations of these parameters, with composition of the mixtures and temperature, have been discussed in terms of molecular interactions occurring in these mixtures. Further, the viscosities of these binary mixtures were calculated theoretically from their corresponding pure component data by using empirical relations, and the results were compared with the experimental findings.  相似文献   

13.
Densities, viscosities and speeds of sound of binary mixtures of ethanol, propan-1-ol, butan-1-ol and pentane-1-ol with n-butyl acetate have been measured over the entire range of composition at temperatures of 298.15, 303.15, 308.15 and 313.15 K and atmospheric pressure. From the experimental densities, viscosities and speeds of sound, the excess molar volumes V E, deviations in viscosity ????, and deviations in isentropic compressibility ???? S have been calculated. The excess molar volumes and deviations in isentropic compressibility are positive for all the binary systems studied over the whole composition, while deviations in viscosities are negative for all of the binary mixtures. The excess molar volumes, deviations in viscosity, and deviations in isentropic compressibility have been fitted to a Redlich?CKister type polynomial equation. FTIR and 1H-NMR studies of these mixtures are also reported.  相似文献   

14.
Densities (ρ), relative permittivities (ε), viscosities (η), and speeds of sound (u) at 298.15?K of binary mixtures of 2-methoxyethanol (1)?+?isobutylamine (2), are reported. From all those data, the excess molar volumes, and deviations from mole fraction additivity of the relative permittivity (Δε), viscosity (Δη), speed of sound (Δu), and isentropic compressibility (Δκ) have been calculated. The results for V E, Δε, Δln?η, Δu, and Δκ are discussed on the basis of intermolecular interactions between the components of the analysed mixtures.  相似文献   

15.
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   

16.
Densities (ρ), speeds of sound (u) and refractive indices (nD ), of the ternary mixture (diethylcarbonate + p-chloroacetophenone + 1-hexanol) and the involved binary mixtures (diethylcarbonate + p-chloroacetophenone, diethylcarbonate + 1-hexanol, and p-chloroacetophenone + 1-hexanol) have been measured over the whole composition range at 303.15 K for the liquid region and at ambient pressure. The data obtained are used to calculate isentropic compressibilities ks , isentropic compressibility deviations Δks and refractive index deviations ΔnD , of the binary and ternary mixtures. The data of isentropic compressibility deviations and refractive index deviations of the binary systems were fitted to the Redlich–Kister equation while the best correlation method for the ternary system was found using the Cibulka equation. The experimental data of the constitute binaries and ternaries are analysed to discuss the nature and strength of intermolecular interactions in these mixtures.  相似文献   

17.
Densities (ρ), viscosities (η), and speeds of sound, (u) of the binary mixtures of 2-propanol with n-alkanes (n-hexane, n-octane, and n-decane) were measured over the entire composition range at 298.15 and 308.15 K and at atmospheric pressure. Using the experimental values of density, viscosity and speed of sound, the excess molar volumes (V E), viscosity deviations (Δη), deviations in speed of sound (Δu), isentropic compressibility (κ s), deviations in isentropic compressibility (Δκ s), and excess Gibbs energies of activation of viscous flow (ΔG* E) were calculated. These results were fitted to the Redlich–Kister type polynomial equation. The variations of these excess parameters with composition were discussed from the viewpoint of intermolecular interactions in these mixtures. The excess properties are found to be either positive or negative depending on the molecular interactions and the nature of liquid mixtures.  相似文献   

18.
Experimental viscosities, η, for pure N,N-dimethylformamide (DMF) and acetone (ACT) and their binary mixtures are measured over the whole composition range as a function of temperature between 298.15 and 313.15 K. The deviations in viscosity, ?η, Gibbs free energy of activation ?G, entropies ?S*, enthalpies ?H of activation of viscous flow have been calculated. The determination of excess molar volumes, E, was calculated from the experimental viscosities for the binary mixtures. The conductor-like screening model is applied to interpret the intermolecular forces. The σ-profile is computed for the N,N-DMF and ACT with conductor-like screening model for real solvents. The experimental results were found to be in good agreement with the theoretical predictions. Moreover, viscosity data were calculated from the theoretical equations of Grunberg and Nissan, Hind et al. and Wilke for the entire systems. All results obtained were averaged experimentally and theoretically in terms of average deviations.  相似文献   

19.
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   

20.
Excess molar volumes (V m E ) and viscosities (η) of the binary mixtures of 1,2-diethoxyethane with di-, tri- and tetrachloromethane have been measured at 298-15 K and atmospheric pressure over the entire mole fraction range. The deviations in viscosities (δlnη) and excess energies of activation (δG*E) for viscous flow have been calculated from the experimental data. The Prigogine-Flory-Patterson (PFP) model has been used to calculateV m E , and the results have been compared with experimental data. The Bloomfield and Dewan model has been used to calculate viscosity coefficients and these have also been compared with experimental data for the three mixtures. The results have been discussed in terms of dipole-dipole interactions between 1,2-diethoxyethane and chloroalkanes and their magnitudes decreasing with the dipole character of the molecules. A short comparative study with results for mixtures with polyethers and chloroalkanes is also described.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号