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1.
Densities and kinematic viscosities have been measured for (1,2-ethanediol + 1-nonanol) over the temperature range from (298.15 to 313.15) K. The speeds of sound in those mixtures within the temperature range from (293.15 to 313.15) K have been measured as well. Using the measurement results, the molar volumes, isentropic compressibility coefficients, molar isentropic compressibilities, and the corresponding excess and deviation values (excess molar volumes, excess isentropic compressibility coefficients, excess molar isentropic compressibilities, differently defined deviations of the speed of sound, and dynamic viscosity deviations) were calculated. The excess Gibbs free energies estimated by the use of the UNIQUAC model are also reported. The excess molar volumes and Gibbs free energies are positive, whereas the compressibility excesses are s-shaped. The excess and deviation values are expressed by Redlich–Kister polynomials and discussed in terms of variations of the structure of the system caused by the participation of two different alcohol molecules in the dynamic intermolecular association process through hydrogen bonding. The effect of temperature is discussed. The predictive abilities of the McAllister equation for viscosities of the mixtures under test have also been examined.  相似文献   

2.
In this work, the physical properties, dynamic viscosities, densities, and speed of sound have been measured over the whole composition range and atmospheric pressure for the binary mixtures (methylcyclopentane with acetone, butanone, and 2-pentanone) at several temperatures T = (293.15, 298.15, and 303.15) K along with the properties of the pure components. Excess molar volumes, isentropic compressibility, deviations in isentropic compressibility and viscosity deviation for the binary systems at the above-mentioned temperatures were calculated and fitted to the Redlich–Kister equation to determine the fitting parameters and the root-mean-square deviations. The UNIQUAC equation was used to correlate the experimental viscosity data. The UNIFAC-VISCO method and ASOG-VISCO method, based on contribution groups, were used to predict the dynamic viscosities of the binary mixtures. The interaction parameters of cycloalkanes with ketones (CHcy/CO) have been determined for their application in the predictive UNIFAC-VISCO method.  相似文献   

3.
Viscosities, densities, and speed of sound have been measured over the whole composition range for (methylcyclopentane with ethanol, 1-propanol, 1-butanol, 2-propanol, 2-butanol, and 2-pentanol) at T = (293.15, 298.15, and 303.15) K and atmospheric pressure along with the properties of the pure components. Excess molar volumes, isentropic compressibility, deviations in isentropic compressibility, and viscosity deviations for the binary systems at the above-mentioned temperatures were calculated and fitted to Redlich–Kister equation to determine the fitting parameters and the root-mean square deviations. UNIQUAC equation was used to correlate the experimental data. Dynamic viscosities of the binary mixtures have been predicted using UNIFAC-VISCO and ASOG-VISCO methods.  相似文献   

4.
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   

5.
Densities and kinematic viscosities have been measured for (1-butanol + 1,4-butanediol) over the temperature range from (298.15 to 318.15) K. The speeds of sound within the temperature range from (293.15 to 318.15) K have been measured as well. Using these results and literature values of isobaric heat capacities, the molar volumes, isentropic and isothermal compressibility coefficients, molar isentropic and isothermal compressibilities, isochoric heat capacities as well as internal pressures were calculated. Also the corresponding excess and deviation values (excess molar volumes, excess isentropic and isothermal compressibility coefficients, excess molar isentropic and isothermal compressibilities, different defined deviation speed of sound and dynamic viscosity deviations) were calculated. The excess values are negative over the whole concentration and temperature range. The excess and deviation values are expressed by Redlich–Kister polynomials and discussed in terms of the variations of the structure of the system caused by the participation of the two different alcohol molecules in the dynamic intermolecular association process through hydrogen bonding at various temperatures. The predictive abilities of Grunberg–Nissan and McAllister equations for viscosities of mixtures have also been examined.  相似文献   

6.
In this work, dynamic viscosities, densities, and speed of sound have been measured over the whole composition range and 0.1 MPa for the binary mixtures (cyclopentane and cyclohexane with ethanol, 1-propanol, and 1-butanol) at several temperatures (293.15, 298.15, 303.15) K along with the properties of the pure components. Excess molar volumes, molar isentropic compression, excess molar isentropic compression, and excess free energy of activation for the binary systems at the above mentioned temperatures, were calculated and fitted to the Redlich–Kister equation to determine the fitting parameters and the root-mean-square deviations. The UNIQUAC equation was used to correlate the experimental viscosity data. The UNIFAC-VISCO method and ASOG-VISCO method, based on contribution groups, were used to predict the dynamic viscosities of the binary mixtures. The interaction parameters of cycloalkanes with primary alcohol (CHcy/-OH) have been determined for their application in the predictive UNIFAC-VISCO method.  相似文献   

7.
Viscosities, densities and speed of sound have been measured over the whole composition range for (2-propanol with octane, or decane, or dodecane) at T=(293.15, 298.15, and 303.15) K and atmospheric pressure along with the properties of the pure components. Excess molar volumes, isentropic compressibility, deviations in isentropic compressibility and viscosity deviations for the binary systems at the above-mentioned temperatures were calculated and fitted to Redlich–Kister equation to determine the fitting parameters and the root-mean-square deviations. Prediction of the dynamic viscosities of this binary mixture from UNIFAC-VISCO and ASOG-VISCO methods has been determined.  相似文献   

8.
Density, speed of sound, and refractive index for the binary systems (butanoic acid + propanoic acid, or 2-methyl-propanoic acid) were measured over the whole composition range and at T = (293.15, 298.15, 303.15, 308.15, and 313.15) K. The excess molar volumes, isentropic compressibilities, excess isentropic compressibilities, molar refractions, and deviation in refractive indices were also calculated by using the experimental densities, speed of sound, and refractive indices data, respectively. The Redlich–Kister smoothing polynomial equation was used to fit the excess molar volume, excess isentropic compressibility and deviation in refractive index data. The thermodynamic properties have been discussed in terms of intermolecular interactions between the components of the mixtures.  相似文献   

9.
Physico-chemical properties viz., density, viscosity, and refractive index at temperatures = (298.15, 303.15, and 308.15) K and the speed of sound at T = 298.15 K are measured for the binary mixtures of methylcyclohexane with ethanol, propan1-ol, propan-2-ol, butan-1-ol, 2-methyl-1-propanol, and 3-methyl-1-butanol over the entire range of mixture composition. From these data, excess molar volume, deviations in viscosity, molar refraction, speed of sound, and isentropic compressibility have been calculated. These results are fitted to the polynomial equation to derive the coefficients and standard errors. The experimental and calculated quantities are used to study the nature of mixing behaviours between the mixture components.  相似文献   

10.
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   

11.
This paper reports measurements of densities for the binary systems of an ionic liquid and an alkanol at T = (298.15, 303.15, and 313.15) K. The IL is trioctylmethylammonium bis(trifluoromethylsulfonyl)imide [OMA]+[Tf2N]? and the alkanols are methanol, or ethanol, or 1-propanol. The speed of sound at T = 298.15 K for the same binary systems was also measured. The excess molar volumes and the isentropic compressibilities for the above systems were then calculated from the experimental densities and the speed of sound, respectively. Redlich–Kister smoothing polynomial equation was used to fit the excess molar volume and the deviation in isentropic compressibility data. The partial molar volumes were determined from the Redlich–Kister coefficients. For all the systems studied, the excess molar volumes have both negative and positive values, while the deviations in isentropic compressibility are negative over the entire composition range.  相似文献   

12.
In this work, density and speed of sound data of binary mixtures of an ionic liquid consisting of {2-hydroxy ethylammonium acetate (2-HEAA) + (water, methanol, or ethanol)} have been measured throughout the entire concentration range, from the temperature of (288.15 to 323.15) K at atmospheric pressure. The excess molar volumes, variations of the isentropic compressibility, the apparent molar volume, isentropic apparent molar compressibility, and thermal expansion coefficient were calculated from the experimental data. The excess molar volumes were negative throughout the whole composition range. Compressibility data in combination with low angle X-ray scattering and NMR measurements proved that the presence of micelles formed due to ion pair interaction above a critical concentration of the ionic liquid in the mixtures. The Peng–Robinson equation of state coupled with the Wong–Sandler mixing rule and COSMO–SAC model was used to predict densities and the calculated deviations were lower than 3%, for binary mixtures in all composition range.  相似文献   

13.
Experimental values of density, viscosity, and refractive index at T = (298.15, 303.15, and 308.15) K while the speed of sound at T = 298.15 K in the binary mixtures of methylcyclohexane with n-hexane, n-heptane, n-octane, n-nonane, n-decane, n-dodecane, and iso-octane are presented over the entire mole fraction range of the binary mixtures. Using these data, excess molar volume, deviations in viscosity, molar refraction, speed of sound, and isentropic compressibility are calculated. All the computed quantities are fitted to Redlich and Kister equation to derive the coefficients and estimate the standard error values. Such a study on model calculations in addition to presentation of experimental data on binary mixtures are useful to understand the mixing behaviour of liquids in terms of molecular interactions and orientational order–disorder effects.  相似文献   

14.
Densities, speeds of sound and refractive indices have been measured for (n -hexane  +  cyclohexane  +  1-hexanol) and its corresponding binaries atT =  298.15 K. In addition, ideal isentropic compressibilities were calculated from the speeds of sound, densities, and literature heat capacities and cubic expansion coefficients. The excess molar volumes and excess isentropic compressibilities, and deviations of the speed of sound and refractive index are correlated by polynomials and discussed.The Nitta–Chao model was used to estimate binary and ternary excess molar volumes, and several empirical equations were also used to calculate the excess and deviation properties.  相似文献   

15.
Densities and viscosities for the four binary liquid mixtures of methyl acrylate, ethyl acrylate, butyl acrylate and methyl methacrylate with hexane-1-ol at temperatures 303.15 and 313.15 K and at atmospheric pressure were measured over the entire composition range. These values were used to calculate excess molar volumes and deviation in viscosities which were fitted to Redlich–Kister polynomial equation. Recently proposed Jouyban Acree model was also used to correlate the experimental values of density and viscosity. The mixture viscosities were correlated by several semi-empirical approaches like Hind, Choudhary–Katti, Grunberg–Nissan, Tamura and Kurata, McAllister three and four body model equations. A graphical representation of excess molar volumes and deviation in isentropic compressibility shows positive nature whereas deviation in viscosity shows negative nature at both temperatures for all four binary liquid mixtures. Positive values of excess molar volumes show that volume expansion is taking place causing rupture of H-bonds in self associated alcohols. The results were discussed in terms of molecular interactions prevailing in the mixtures.  相似文献   

16.
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   

17.
Densities, speeds of sound, and refractive indices of 12 binary systems of alkanes (hexane, heptane, octane, and nonane) with aromatics (benzene, or toluene, or ethylbenzene) at T = 313.15 K and at atmospheric pressure were determined over the whole composition range, and are presented in this paper. From the experimental results, the derived and excess properties (isentropic compressibility, excess molar volumes, and excess molar isentropic compressibility) at T = 313.15 K were calculated and satisfactorily fitted to the Redlich–Kister equation.  相似文献   

18.
Mixtures of tetralin (1,2,3,4-tetrahydronaphthalene), an aromatic cyclic molecule, and n-decane present asymmetries in chemical nature, shape, and chain length, and are frequently found, e.g., in naphtha or kerosene fractions. Aiming at understanding the impact of these asymmetries on some thermophysical properties, this work presents densities, sound velocities, and refractive indexes for this binary system along with the properties of the pure components at T = (293.15, 303.15, 313.15, 323.15, 333.15, and 343.15) K over whole composition range and atmospheric pressure. From these data, the following derived properties were obtained: isentropic compressibility, molar refractivity, excess volume, excess isentropic compressibility, molar refractivity deviations, and thermal expansion coefficient. Several sound velocity mixing rules were tested, and the best result was for Nomoto mixing rule. Pure component densities and sound velocities were correlated with Prigogine–Flory–Patterson (PFP) model. The binary interaction parameter for this model was obtained from correlation of excess volumes and isentropic compressibilities. This model correlated experimental densities very well and correlated reasonably well sound velocities and thermal expansion coefficient.  相似文献   

19.
The densities (ρ) and speeds of sound (u) have been measured over the whole composition range for (butan-1-ol with hexane, or octane, or decane) at T = (298.15, 303.15, and 308.15) K and atmospheric pressure along with the properties of the pure components. Viscosities (η) of these binary mixtures have also been measured over the entire composition range at T = 298.15 K. Experimental values of density, viscosity and speed of sound have been used to evaluate excess properties viz. excess molar volumes (VE), deviation in viscosity (Δη), deviation in speeds of sound (Δu), deviation in isentropic compressibility (Δκs) and excess Gibbs free energy of activation of viscous flow (ΔG1E). The excess properties have been correlated using the Redlich–Kister polynomial equation. The sign and magnitude of these excess properties have been used to interpret the results in terms of intermolecular interactions and structural effects. The viscosity data have also been correlated by Grunberg and Nissan, Tamura–Kurata, and Hind correlation equations.  相似文献   

20.
In this work, our objective is to contribute to the knowledge of the mixtures (alcohol + polyalkyl ether glycol) used in absorption refrigeration systems and heat pumps. The determination of different thermophysical properties is essential to understand the interactions among different molecules in liquid mixtures. Therefore, experimental data of speed of sound and density together with calculated values of isentropic compressibility for the refrigerant-absorbent system (methanol + polyethylene glycol dimethyl ether 250) (or Pegdme 250) have been gathered here over the whole range of composition at temperatures from T=293.15 to 333.15 K and atmospheric pressure. The two previous experimental properties were measured with a digital vibrating tube analyser Anton Paar DSA-48. Also, the excess molar volumes and the increments of the speed of sound and the isentropic compressibility have been determined for each composition and they were fitted to a variable-degree polynomial equation.  相似文献   

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