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1.
《Fluid Phase Equilibria》2002,202(2):385-397
Densities, speeds of sound and heats of mixing for the ternary system cyclohexane + 1,3-dioxolane + 1-butanol have been measured at atmospheric pressure at the temperatures of 298.15 and 313.15 K. Excess molar volumes, excess isentropic compressibilities and excess molar enthalpies have been calculated from experimental data and fitted by Cibulka equation. Excess molar properties were analysed in terms of molecular interactions and structural and packing effects.  相似文献   

2.
《Fluid Phase Equilibria》2003,211(1):61-73
Densities, speeds of sound and heats of mixing for the ternary system hexane+1,3-dioxolane+1-butanol have been measured at atmospheric pressure at the temperatures of 298.15 and 313.15 K. Excess molar volumes, excess isentropic compressibilities, and excess molar enthalpies have been calculated from experimental data and fitted by Cibulka equation. Excess molar properties were analysed in terms of molecular interactions as well as structural and packing effects.  相似文献   

3.
Densities and speeds of sound for the ternary system 1-butanol+1,4-dioxane+cyclohexane have been measured at the temperatures of 298.15 and 313.15 K. Excess molar volumes and excess isentropic compressibilities have been calculated from experimental data and fitted by the Redlich-Kister equation for ternary mixtures. The ERAS model has been used to calculate excess molar volumes of the ternary mixture from parameters obtained from the constituent binary mixtures.  相似文献   

4.
Viscosities of the ternary system n-hexane+1,3-dioxolane+1-butanol and the binary system n-hexane+1,3-dioxolane have been measured at atmospheric pressure at 298.15 and 313.15 K. Viscosity deviations for the binary and ternary systems were calculated from experimental data and fitted to Redlich–Kister and Cibulka equations, respectively. The group contribution method proposed by Wu has been used to predict the viscosity of all mixtures.  相似文献   

5.
In this work, the applicability of the free length and the collision factor theories (FLT and CFT, respectively) to predict multicomponent changes of isentropic compressibilities is analysed and compared. To this end, appropiate expansions for ternary mixtures were derived from the original works, and then applied to a mixture containing unlike compounds in terms of functional molecular groups. Experimental data of excess molar volumes from open literature and new experimental isentropic compressibilities of the mixture chlorobenzene?+?n-hexane?+?(n-heptane or n-octane) were used to compute the parameters. A good accuracy was obtained when ternary prediction is attempted in this partially soluble mixture at different temperatures by the collision factor theory. These results show the versatility of this model for estimation in complex multicomponent mixtures with phases splitting.  相似文献   

6.
《Fluid Phase Equilibria》1999,154(1):123-138
Excess molar volumes, changes of refractive indices, and changes of isentropic compressibilities of the ternary mixture benzene (1)+cyclohexane (2)+2-methyl-2-butanol (3), and the corresponding binary mixtures benzene (1)+2-methyl-2-butanol (3), and cyclohexane (2)+2-methyl-2-butanol (3) have been evaluated from density, refractive index, and speed of sound measurements at 298.15 K, and atmosphere. These derived properties of binary, and ternary mixtures were fitted to Redlich–Kister, and Nagata equations, respectively, the correlation parameters being gathered. In spite of the high non-ideality observed, the excess molar volumes were satisfactorily predicted by means of cubic equations of state with simple mixing rules.  相似文献   

7.
The aim of this work is to complete our studies on physical properties of binary mixtures of alkane+1-alkanols. This work reports densities, refractive indices, speeds of sound and isentropic compressibilities of the mixture octane + 1-butanol at different temperatures, from 288.15 to 308.15 K. From the experimental values, the corresponding excess and deviation values were computed (excess molar volumes, changes of refractive index on mixing, changes of speed of sound on mixing and changes of isentropic compressibilities on mixing). The results were fitted to variable-degree polynomials. Excess molar volumes were compared with the predictions of Nitta-Chao Group Contribution Model. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

8.
Densities and speeds of sound of the binary mixtures 1,3-dioxolane + 1-butanol, 1,3-dioxolane + 2-butanol, 1,4-dioxane + 1-butanol, and 1,4-dioxane + 2-butanol have been measured at 25 and 40°C. The excess molar volumes and excess isentropic compressibility coefficients were calculated from experimental data and fitted to a Redlich–Kister polynomial function. Results were analyzed in terms of molecular interactions and compared with literature data.  相似文献   

9.
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   

10.
Surface tensions (sigma) for [1,3-dioxolane+methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, and 1-pentanol] and excess molar volumes (v(E)) for [1,3-dioxolane+methanol, ethanol, 1-propanol, 2-propanol, and 2-butanol] at the temperature 298.15 K and normal atmospheric pressure have been determined as a function of mole fractions. The magnitude of these experimental quantities is discussed in terms of the nature and type of intermolecular interactions in binary mixtures. In order to analyze the surface tension behavior, the extended Langmuir (EL) model was used and the results obtained for the systems containing 1,3-dioxolane were compared with those of other formerly published series: [1,4-dioxane+alkanes] and [1,4-dioxane+alcohols].  相似文献   

11.
Speeds of sound, uijk, of 1,3-dioxolane or 1,4-dioxane (i) + water (j) + formamide or dimethylformamide (k) ternary mixtures and of their binary subsystems, uij, of 1,3-dioxolane or 1,4-dioxane (i) + formamide or dimethylformamide (j), and water (i) + formamide or dimethylformamide (j) have been measured over the entire composition range at 308.15 K. The experimental data have been used to evaluate the excess isentropic compressibilities of binary (κsE)ij and ternary (κsE)ijk mixtures using their densities calculated from molar excess volume data. The Moelwyn-Huggins concept [M. L. Huggins, Polymer 12, 389 (1971)] of interaction between the surfaces of components of a binary mixture has been employed to evaluate the excess isentropic compressibilities (using the concept of connectivity parameter of third degree of a molecule, 3ξ, which in turn depends on its topology) of binary mixtures, and this method has been extended to predict excess compressibilities of ternary mixtures. Values of (κsE)ij and (κsE)ijk have also been calculated by the Flory theory. It was observed that (κsE)ij and (κsE)ijk predicted by the Moelwyn-Huggins approach compare well with calculated and experimental values.  相似文献   

12.
In this study, the applicability of the Free Length and the Collision Factor theories to predict multicomponent changes of isentropic compressibilities is analysed and compared. To this end, appropriated expansions for ternary mixtures were derived from the original studies where these theories are developed, and then applied to a mixture containing unlike compounds in terms of functional molecular groups. Experimental data of excess molar volumes from open literature and new experimental isentropic compressibilities of the mixture chlorobenzene?+?n-hexane?+?(n-undecane or n-dodecane) were used to compute the parameters. A good accuracy was obtained when ternary prediction is attempted in this partially soluble mixture at different temperatures by the both methods. These results show the versatility of the models for estimation in complex multicomponent mixtures.  相似文献   

13.
The speed of sound, Uij 1,3-dioxolane (D) in binary mixtures (ij) with benzene, cyclohexane, n-hexane or n-heptane and Uijk for 1,3-dioxolane in ternary mixtures (ijk) with the same hydrocarbons have been measured as a function of composition at 298.15 K. The observed data have been utilised to evaluate excess isentropic compressibility of binary, (κsE)ij and ternary (κsE)ijk mixtures using density and speed of sound values of the binary and ternary mixtures. The Moelyn-Huggins concept of interaction between the molecular surfaces of the components of a binary mixture [Polymer 12 (1971) 389] has been extended to evaluate excess isentropic compressibility of the studied binary and ternary mixtures. It has been observed that κsE values predicted by a graph-theoretical approach using connectivities of third degree for binary mixtures compare reasonably well with their corresponding experimental values and κsE for ternary mixtures are of the same sign and order of magnitude.  相似文献   

14.
Ultrasonic speeds and isentropic compressibilities were measured at 298.15 K in the water-rich region of aqueous solutions of water + 2-ethoxyethanol (2EE) + t-butanol. The excess properties of ultrasonic speed and isentropic compressibility were also calculated and have been discussed in terms of molecular interactions. The concentrations of t-butanol at which ultrasonic speed becomes maximum and isentropic compressibility becomes minimum are found to decrease with increase in the concentration of 2EE in the cosolvent (aqueous 2EE). This behavior indicates that the aqueous ternary solutions are less structured than aqueous t-butanol. This behavior is explained as due to a decrease in the ability of t-butanol to form clathrate hydrates owing to the presence of 2EE. When the concentration of 2EE in the cosolvent (x 2EE) > 0.14, ultrasonic speed decreases and isentropic compressibility increases with concentration of t-butanol indicating that the ternary solution behaves as normal solution wherein any further addition of 2EE or t-butanol leads to destabilization of the hydrogen bonded structure of water and t-butanol looses its ability to form clathrate hydrates in aqueous solutions.  相似文献   

15.
《Fluid Phase Equilibria》1998,145(1):115-128
Densities of the liquid mixtures (n-hexane+1-chlorobutane) and (1-butanol+n-hexane+1-chlorobutane) have been measured by the vibrating tube technique at 298.15 K and 313.15 K. With these densities, excess molar volumes were calculated. An extended version of the so-called ERAS model has been used for describing VE of the complete ternary system at 298.15 K. Qualitatively the ERAS-model gives an adequate representation of this system, being similar the shapes of both the experimental and the predicted curves.  相似文献   

16.
《Fluid Phase Equilibria》1996,118(2):227-240
Densities, ϱ, and speeds of sound, u, have been measured for the ternary mixture {benzene + cyclohexane + hexane} and the corresponding binary mixtures {benzene + cyclohexane}, {benzene + hexane} and {cyclohexane + hexane}, at the temperature 298.15 K. Using these results, the isentropic compressibilities, κs, the excess isentropic compressibilities, κsE, and the speeds of sound deviations, Δu, have been calculated for both the binary mixtures and the ternary system. Excess isentropic compressibilities, κsE, and the speeds of sound deviations, Δu, have been fitted to the Redlich-Kister equation in the case of binary mixtures, while the equation of Cibulka was used to fit the values relating to the ternary system. The empiric equations of Redlich-Kister, Tsao-Smith, Kohler and Colinet have been applied in order to predict the κsE and Δu of ternary mixtures from the binary contributions.  相似文献   

17.
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   

18.
The following properties of mixtures of the butanols with cyclohexane were measured over the whole range of composition: 1-butanol+cyclohexane and 2-butanol+cyclohexane; excess enthalpies at 15, 25, 35 and 45°C, excess volumes at 25 and 45°C, activity coefficients and excess Gibbs free energies at 45°C. 2-Methylpropan-2-ol (tertiary butanol)+cyclohexane; excess enthalpies at 26, 35, and 45°C, excess volumes at 26 and 45°C, activity coefficients and excess Gibbs free energies at 45°C. From these data, activity coefficients at the temperatures of the excess enthalpy measurements below 45°C have been computed, as a source of test data for models of alcohol association through hydrogen bonding.  相似文献   

19.
Densities and speeds of sound at atmospheric pressure and temperatures of (283.15, 298.15, and 313.15) K for the binary mixtures formed by n-hexane or n-heptane with isomeric chlorobutanes were determined. Afterwards excess volumes, excess isentropic compressibilities and excess speeds of sound were calculated using the experimental data and correlated using a Redlich–Kister type equation. Finally, the results were studied using the Prigogine–Flory–Patterson theory showing excellent predictions for speed of sound and isentropic compressibility values of mixtures as well as a strong influence of the interactional contribution term for excess volume values.  相似文献   

20.
Measurements of ultrasonic speeds, isentropic compressibilities and viscosities were carried out for six ternary mixtures namely dimethylsulphoxide (1) + 1,2-dichlorobenzene (2) + 1-alkanols (3) at 303.15 K. The 1-alkanols include 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, 1-heptanol and 1-octanol. The ultrasonic speeds of these ternary mixtures were also evaluated on the basis of Jacobson's free length theory and Schaaff's collision factor theory. From the viscosity data, deviations in viscosity and interaction parameters for various models were also calculated. An attempt has also been made to explain the nature of intermolecular interactions in the light of deviation in isentropic compressibilities and interaction parameter.  相似文献   

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