Densities and viscosities for binary mixtures of phenetole with 1-pentanol, 1-hexanol, 1-heptanol, 1-octanol, 1-nonanol,and 1-decanol at different temperatures

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 (V^E), 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.     

Physico-chemical properties of binary mixtures of 1-butanol with chloroethanes or chloroethenes at 298.15 K

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 Δκ_s 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.     

ERAS modeling of the excess molar enthalpies of binary liquid mixtures of 1-pentanol and 1-hexanol with acetonitrile at atmospheric pressure and 288, 298, 313 and 323 K

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.     

Thermodynamics of binary liquid mixtures of cyclopentane with 2-propanol, 1-butanol and 2-butanol at different temperatures

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 _m^E/∂T)_P and (∂H _m^E/∂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.     

Intermolecular interactions in mixtures of ethyl formate with methanol,ethanol, and 1-propanol on density,viscosity, and ultrasonic data

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.     

Molecular interactions in 1-pentanol +2-methyl-2-butanol mixtures: Static dielectric constant,viscosity and refractive index investigations at 5, 25 and 45°C

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.     

Relative permittivity data of binary mixtures containing 2-butanol, 2-butanone,and cyclohexane

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.     

Excess enthalpies of binary mixtures of 2-methyl-1-pentanol with hexane isomers

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.     

Molecular interactions and structures in ethylene glycol-ethanol and ethylene glycol-water solutions at 303 K on densities, viscosities, and refractive indices data

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.     

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

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. V^E 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 V^E 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.     

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

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.     

Excess enthalpies of binary mixtures of 2-ethyl-1-butanol with hexane isomers

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.     

Bubble point measurements of binary mixtures formed by 1-hexanol with selected nitro-compounds and substituted benzenes at 95.6 kPa

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.     

Dielectric properties of binary mixtures of three butanediols with 1,4-dioxane and 2-ethyl-1-hexanol at T = 298.2 K

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.     

Thermodynamic investigation of methyl salicylate/1-pentanol binary system in the temperature range from 278.15 K to 303.15 K

Densities (ρ), speeds of sound (u), isentropic compressibilities (k_s), refractive indices (n_D), and surface tensions (σ) of binary mixtures of methyl salicylate (MSL) with 1-pentanol (PEN) have been measured over the entire composition range at the temperatures of 278.15 K, 288.15 K, and 303.15 K. The excess molar volumes (V^E), excess surface tensions (σ^E), deviations in speed of sound (Δu), deviations in isentropic compressibility (Δk_s), and deviations in molar refraction (ΔR) have been calculated. The excess thermodynamic properties V^E, σ^E, Δu, Δk_s, and ΔR were fitted to the Redlich–Kister polynomial equation and the A_k coefficients as well as the standard deviations (d) between the calculated and experimental values have been derived. The surface tension (σ) values have been further used for the calculation of the surface entropy (S^S) and the surface enthalpy (H^S) per unit surface area. The lyophobicity (β) and the surface mole fraction $(x_2^{\text{S}})$ of the surfactant component PEN have been also derived using the extended Langmuir model. The results provide information on the molecular interactions between the unlike molecules that take place at the surface and the bulk.     

Molecular interactions in binary mixtures of non-electrolytes: Molar excess enthalpies

Molar excess enthalpies, H^E, for pyridine (i) + α-picoline (j), + β-picoline (j), + γ-picoline (j); pyridine (i) + cyclohexane (j); β-picoline (i) + cyclohexane (j); methylenebromide (i) + pyridine (j), + β-picoline (j) mixtures have been measured calorimetrically as a function of temperature and composition. The H^E data at 298.15 and 308.15 K have been analysed in terms of the Sanchez and Lacombe theory and the “graph theoretical approach”. The graph theoretical approach describes the H^E data well for all these mixtures. This approach has been critically examined and it is found to provide an insight into the nature of molecular interactions between the components of these mixtures. NMR studies on methylene bromide (i) + β-picoline (j) andβ-picoline (i) + pyridine (j) further support these conclusions.     

Thermophysical properties of 1-hexanol over the temperature range from 303 K to 503 K and at pressures from the saturation line to 400 MPa

Isobaric thermal expansivities, _P(T,p), of 1-hexanol have been measured in a pressure-controlled scanning calorimeter from just above the saturation vapour pressure to 400 Mpa at temperatures from 302.6 K to 503.15 K. The specific volume isotherm, v(T_R,p), at T_R=302.6 K has been derived from measurements of isothermal compressibilities up to 400 MPa and from the specific density at atmospheric pressure. Specific volumes, isothermal compressibilities, thermal pressure coefficients, and isobaric and isochoric heat capacities for the whole pressure and temperature range are derived from these data and from literature data on the saturation vapour pressures and on the isobaric heat capacities at atmospheric or saturation vapour pressure.