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1.
《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   

2.
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   

3.
This work reports experimental data on the excess molar enthalpy as a function of composition of acetonitrile + 1-pentanol and acetonitrile + 1-hexanol mixtures at 288.15, 298.15, 313.15 and 323.15 K under atmospheric pressure. The data show positive values over the whole composition range for both systems and for all temperatures studied, they also increase with temperature and with alkanol chain length. The experimental curves have a parabolic shape with maximum point around 0.5 mole fraction. The extended real associated solution (ERAS) model was applied to correlate the experimental data. The ERAS model adequately described the main features of the behavior of the mixtures.  相似文献   

4.
Densities and speeds of sound of the cyclopentane with 2-propanol, 1-butanol and 2-butanol are measured over the whole composition range at different temperatures in the range 288.15–308.15 K and atmospheric pressure using Anton Paar DSA 5000 densimeter. The experimental densities and speeds of sound have been used to calculate excess molar volumes, excess molar isentropic compressibilities and excess intermolecular free length. The partial molar volumes and apparent molar volumes at infinite dilution have also been calculated. The mixing quantities like (∂V mE/∂T)P and (∂H mE/∂P)T have been calculated at T = 298.15 K and these values are compared with the values calculated from Flory’s theory at equimolar composition.  相似文献   

5.
Density (ρ), viscosity (η), and ultrasonic velocity (U) have been measured for binary mixtures of ethyl formate with methanol, ethanol, and 1-propanol at 303 K. From the experimental data, adiabatic compressibility (β), acoustic impedance (Z), viscous relaxation time (τ), free length (L f ), free volume (V f ), internal pressure (π i ), and Gibbs free energy (ΔG) have been deduced. It is shown that strength of intermolecular interactions between ethyl formate with selected 1-alcohols were in the order of methanol < ethanol < 1-propanol.  相似文献   

6.
Static dielectric constants, refractive indices and viscosities of 1-pentanol +2-methyl-2-butanol mixtures were measured at 5, 25 and 45°C. The results show that the mixing of the two isomers modifies the polarizability and the resistence of viscous flow of the system depending on the composition and temperature. Short range intermolecular interactions producing hetero-alcohol open dimers are considered.  相似文献   

7.
Relative permittivity measurements were made on binary mixtures of (1,2-butanediol + 2-ethyl-1-hexanol) and (1,2-butanediol + 1,4-dioxane) for various concentrations at T = (298.2, 308.2, and 318.2) K. The molecular dipole moments were determined using Guggenheim–Debye method in the temperature range of (298.2 to 318.2) K. The variations of effective dipole moment and correlation factor, g, with the mole fraction in these materials were investigated using Kirkwood–Frohlich equation. The pure compounds showed a negative and small temperature coefficient of effective dipole moment. In order to obtain valuable information about heterogeneous interaction (interactions between the unlike molecules), the Kirkwood correlation factor, the Bruggeman dielectric factor and the excess permittivity were calculated. In addition, in order to predict the permittivity data of polar-apolar binary mixtures, five mixing rules were applied.  相似文献   

8.
The rate constants for the reaction between chlorine atoms and either 5-methyl-2-hexanol, 2,2-dimethyl-3-hexanol, or 2,4,4-trimethyl-1-pentanol at 298 K were determined using the relative method with 2-butanol and 1-pentanol as reference compounds. The values obtained for 5-methyl-2-hexanol, 2,2-dimethyl-3-hexanol, and 2,4,4-trimethyl-1-pentanol (k × 1010 cm3 molec−1 s−1) were, respectively, (2.64 ± 0.5), (2.72 ± 0.5), and (2.50 ± 0.4), in agreement with the values of the rate constants reported in bibliography for similar alcohols and the values estimated by structure activity relationship methods. The photooxidation products of 2,4,4-trimethyl-1-pentanol initiated by chlorine atoms were identified (formaldehyde, 2-propanone, 2,2-dimethyl propanal, 4,4,-dimethyl-2-pentanone, and 3,3-dimethylbutanal), and the reaction mechanism was determined.  相似文献   

9.
Density and viscosity were determined for binary mixtures of {hyper-branched polymer, Boltorn H2004 (B-H2004) + 1-alcohol (1-butanol, 1-hexanol, and 1-octanol)} at T = (298.15, 308.15, 318.15, 328.15, and 338.15) K and of {B-H2004 + methyl tert-butyl ether (MTBE)} at T = (298.15, 308.15, and 318.15) K and ambient pressure. The temperature dependence of density and viscosity is described by linear regression and by the Vogel–Fucher–Tammann equation, respectively. Excess volumes for the system {B-H2004 + MTBE} are presented as a function of mass fraction. Viscosity deviations were calculated and correlated by the Redlich–Kister polynomial expansions using also the mass fractions. The polynomial correlations describe the variation of viscosity with composition. A qualitative discussion on these quantities in terms of molecular interactions is reported.  相似文献   

10.
Relative permittivity measurements were made on binary mixtures of (2-butanol + 2-butanone) and (2-butanol or 2-butanone + cyclohexane) for various concentrations at T = (298.2, 308.2, and 318.2) K. Some experimental results are compared with those obtained from theoretical calculations and interpreted in terms of homo- and heterogeneous interactions and structural effects. The molecular dipole moments were determined using Guggenheim–Debye method within the temperature range of (298.2 to 318.2) K. The variations of effective dipole moment and correlation factor, g, with the mole fraction in these materials were investigated using Kirkwood–Frohlich equation. The pure compounds showed a negative and small temperature coefficient of effective dipole moment. In order to obtain valuable information about heterogeneous interaction (interactions between the unlike molecules), the Kirkwood correlation factor, the Bruggeman dielectric factor and the excess permittivity were calculated. In order to predict the permittivity data of polar–apolar binary mixtures, five mixing rules were applied.  相似文献   

11.
Kimura, F. and Benson, G.C., 1982. Excess enthalpies of binary mixtures of 2-methyl-1-pentanol with hexane isomers. Fluid Phase Equilibria, 8:107-112.Molar excess enthalpies, measured in a flow microcalorimeter, are reported for binary mixtures of 2-methyl-1-pentanol with n-hexane and its four isomers. There is a roughly linear correlation between the results for equimolar mixtures and the mean number of gauche conformations of the isomer.  相似文献   

12.
Molecular interactions and structural fittings in binary ethylene glycol + ethanol (EGE, x EG = 0.4111–0.0418) and ethylene glycol + water (EGW, x EG = 0.1771–0.0133) mixtures were studied through the measurement of densities (ρ), viscosities (η), and refractive indices (n D ) at 303.15 K. Excess viscosities (η E ), molar volumes (V m ), excess molar volumes (V m E ), and molar retractions (R M ) of the both binary systems were computed from measured properties. The measured and computed properties have been used to understand the molecular interactions in unlike solvents and structural fittings in these binary mixtures.  相似文献   

13.
Chandramouli, J., Choudary, N.V., Krishnaiah, A. and Naidu, P.R., 1982. Thermodynamic properties of binary liquid mixtures involving weak interactions. Part 1. Excess volumes of binary mixtures of 1-chlorobutane with normal alkanols at 303.15 K. Fluid Phase Equilibria, 8: 87–92Excess volumes for binary mixtures of 1-chlorobutane with 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, 1-heptanol and 1-octanol have been determined at 303.15 K. VE is positive over the whole range of composition for the mixtures of 1-chlorobutane with 1-propanol and 1-butanol. An inversion in the sign of VE is observed over certain ranges of concentration of the halogenated alkane in the remaining four mixtures. The results are explained in terms of depolymerisation of hydrogen-bonded alcohol aggregates, decrease in dipolar association, and weak hydrogen-bonding interaction of the type Cl- - - HO between unlike molecules.  相似文献   

14.
《Thermochimica Acta》1987,112(2):187-195
Isothermal vapor-liquid equilibrium data are presented for the binary acetonitrile-1-butanol and ternary 1-butanol-acetonitrile-benzene systems at 60 °C. The experimental results are well correlated with the UNIQUAC associated-solution model.  相似文献   

15.
Henry’s law constants and infinite dilution activity coefficients of cis-2-butene, dimethylether, chloroethane, and 1,1-difluoroethane in methanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutanol, tert-butanol, 1-pentanol, 2-pentanol, 3-pentanol, 2-methyl-1-butanol, 3-methyl-1-butanol, and 2-methyl-2-butanol in the temperature range of 250 K to 330 K were measured by a gas stripping method and partial molar excess enthalpies were calculated from the activity coefficients. A rigorous formula for evaluating the Henry’s law constants from the gas stripping measurements was used for the data reduction of these highly volatile mixtures. The uncertainty is about 2% for the Henry’s law constants and 3% for the estimated infinite dilution activity coefficients. In the evaluation of the infinite dilution activity coefficients, the nonideality of the solute such as the fugacity coefficient and Poynting correction factor cannot be neglected, especially at higher temperatures. The estimated uncertainty of the infinite dilution activity coefficients includes 1% for nonideality.  相似文献   

16.
Molar excess enthalpies, measured at 298.15 K in a flow microcalorimeter, are reported for binary mixtures of 2-ethyl-1-butanol with the five isomeric hexanes. The results are compared with previously published excess enthalpies for mixtures of 1-hexanol and 2-methyl-1-pentanol with the same hexane isomers.  相似文献   

17.
Bubble point measurements (at 95.6 kPa) over the entire composition range are carried out for the binary mixtures formed by 1-hexanol with the: nitro-compounds (acetonitrile, acrylonitrile N,N-dimethyl formamide and aniline) and substituted benzenes (o-xylene, chlorobenzene, and nitrobenzene), employing a Swietoslawski type ebulliometer. Wilson model is found to represent the measured liquid phase composition versus bubble point temperature data well. Computed values of the vapor phase mole fractions and liquid phase activity coefficients are tabulated and briefly discussed.  相似文献   

18.
19.
Experimental results of dielectric investigations for solutions of the three butanediols {2,3-butanediol (2,3BD), 1,3-butanediol (1,3BD), and 1,4-butanediol (1,4BD)}, in 1,4-dioxane (1,4DX) are reported for various mole fractions at T = 298.2 K. Values of relative permittivity were measured at 100 kHz. The molecular dipole moments were determined using Guggenheim method. The variations of effective dipole moment and correlation factor, g, with mole fraction in these materials were investigated using Kirkwood–Frohlich equation. Dielectric measurements were also carried out on binary polar mixtures of the butanediols with 2-ethyl-1-hexanol (2EH) for various concentrations at T = 298.2 K. The Kirkwood correlation factor, the Bruggeman factor, and the excess permittivity were determined.  相似文献   

20.
Refractive indices for the ternary mixtures (benzene  +  1-pentanol  +  anisole), (cyclohexane  +  1-pentanol  +  anisole), and (benzene  +  cyclohexane  +  anisole) at T =  298.15 K and atmospheric pressure over the whole mole fraction range are reported. The corresponding derived property was calculated from the experimental data, and fitted to the Cibulka equation, such parameters being gathered. The application of the Heller equation in order to predict the excess molar volumes from experimental refractive index on mixing was studied with different mixing rules, a qualitative accuracy being obtained for the mixtures containing 1-pentanol due to the nonlinear character of its refractive index on mixing.  相似文献   

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