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1.
《Fluid Phase Equilibria》1999,161(1):191-204
The excess molar volume VE, viscosity deviation Δη, excess viscosity ηE, and excess Gibbs energy of activation ΔG*E of viscous flow have been investigated from the density ρ and viscosity η measurements of eight binary mixtures of butylamine with ethanol, propanol, butanol, pentanol, hexanol, heptanol, octanol and decanol over the entire range of mole fractions at 303.15 and 313.15 K. The viscosity data have been correlated with the equations of Grunberg and Nissan [L. Grunberg, A.H. Nissan, Nature 164 (1949) 799–800], Tamura and Kurata [M. Tamura, M. Kurata, Bull. Chem. Soc. Jpn. 25 (1952) 32–37], Hind et al. [R.K. Hind, E. McLaughlin, A.R. Ubbelohde, Trans. Faraday Soc. 56 (1960) 328–334], Katti and Chaudhri [P.K. Katti, M.M. Chaudhri, J. Chem. Eng. Data 9 (1964) 442–443], McAllister [R.A. McAllister, AIChE J. 6 (1960) 427–431], Heric [E.L. Heric, J. Chem. Eng. Data 11 (1966) 66–68], and of Auslaender [G. Auslaender, Br. Chem. Eng. 10 (1965) 196]. The systems studied exhibit very strong cross association through strong O–H⋯N bonding between –OH and –NH2 groups. As a consequence of this strong intermolecular association, all eight systems have very large negative VE. Except butylamine+ethanol mixture, the magnitude of negative deviations in viscosity increases with chain length of alkanol.  相似文献   

2.
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   

3.
Ultrasonic velocity, density and viscosity of the ternary mixture of toluene + chloroform + cyclohexane, were measured at 303.15, 308.15, and 313.15 K. The thermodynamically parameters such as adiabatic compressibility (??), intermolecular free length (L f), free volume (V f), internal pressure (?? i ), acoustic impedance (Z), molar sound velocity (R), and molar compressibility (W) have been obtained from the experimental data for all the mixtures, with a view to investigate the exact nature of molecular interaction. Adiabatic compressibility and intermolecular free length decrease with increase in concentration and temperature. The other parameters show almost increasing concentration of solutes. These parameters have been further used to interpret the molecular interaction part of the solute and solvent in the mixtures.  相似文献   

4.
5.
《Fluid Phase Equilibria》2004,215(1):61-70
Isentropic compressibilities κS, and excess isentropic compressibilities κSE have been determined from measurements of speeds of sound u and densities ρ of 14 binary mixtures of triethylamine (TEA) and tri-n-butylamine (TBA) with n-hexane, n-octane, iso-octane, n-propylamine, n-butylamine, n-hexylamine and n-octylamine. The relative magnitude and sign of κSE have been interpreted in terms of molecular interactions and interstitial accommodation. The values of κSE for TEA + alkane are positive while for TBA + alkane are negative. The values of κSE for TEA + primary amine become progressively less positive and eventually to negative with the increase in chain length of alkylamine. In case of TBA + primary amine, the values of κSE increase from n-propylamine to n-butylamine, and then decrease with chain length of primary amine. The experimental speeds of sound u have been analyzed in terms of collision factor theory, free length theory and Prigogine–Flory–Patterson statistical theory of solutions.  相似文献   

6.
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   

7.
The properties associated with the liquids and liquid mixtures like density, and excess molar volume find extensive application in chemical engineering design. These properties are important from practical and theoretical point of view to understand liquid theory and provide information about molecular interactions. The objective of the present paper is to determine density (ρ) of a binary liquid mixture of o-anisaldehyde and chlorobenzene over the entire composition range at 303.15, 313.15, and 323.15 K. Excess molar volume (V E) from the ideal behavior over the entire mole fraction range was calculated. Excess molar volume was fitted to Redlich-Kister type equation. It was found that in all cases, the experimental data obtained fitted with the values correlated by the model very well. The molecular interactions existing between the components were discussed. The article is published in the original.  相似文献   

8.
The densities and viscosities of tetra-n-alkylammonium bromides, R4NBr (R=CH3 to C4H9), NaBPh4 and NaBr have been measured in 0, 10, 30, 50, 70, 90, and 100 wt % ethanol + water at 303.15 K. From the densities, apparent and limiting partial molar volumes of the electrolytes and ions in these mixture have been evaluated. The viscosity data have been analyzed with the help of Jones-Dole equation and the viscosity B-coefficients have been determined. The viscosity B-coefficients are further split up in to their ionic contributions.  相似文献   

9.
Excess molar volumes at 303.15 K for the binary mixture of ethylene glycol+, diethylene glycol+, triethylene glycol+ and tetraethylene glycol+ γ-butyrolactone were determined from precise density measurements over the whole mole fraction range. The excess molar volumes are positive over the whole mole fraction range for ethylene glycol and diethylene glycol systems. For triethylene glycol and tetraethylene glycol systems, VE curves are sigmoid with a positive lobe at low mole fraction of glycol and a negative lobe at high mole fraction. The excess molar volumes VE, results are interpreted qualitatively in terms of several opposing effects.  相似文献   

10.
11.
《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   

12.
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   

13.
The molar excess enthalpies of binary mixtures of pyridine with C6–C9 n-alkanes have been measured at 313.15 K in the entire composition range. The measuredH E values were compared with those calculated by means of the Prigogine-Flory-Patterson theory and by the ERAS method.
Zusammenfassung Die molaren Überschußenthalpien binärer Mischungen von Pyridin mit C6–C9 n-Alkanen wurden bei 313,15 K im ganzen Zusammensetzungsbereich gemessen. Die gemessenenH E Werte wurden mit denen verglichen, die mit Hilfe von Prigogine-Flory-Patterson Theorie und nach der ERAS-Methode berechnet wurden.

313,5 n- (6-9) ce . -- (ERAS).
  相似文献   

14.
15.
Excess viscosities, ηE and molar excess volumes VE were obtained for binary mixtures of 1,2-dichloroethane and chlorinated methanes and for pseudobinary mixtures of 1,2-dichloroethane and equimolar binary mixtures from chlorinated methanes at 303.15 K. The chlorinated methanes include carbon tetrachloride, chloroform and dichloromethane. Grunberg—Nissan interaction parameter d and interaction energy for flow of activation Wvis were also presented. The relationship between the ηE's and the VE's has been quantitively considered using Singh's equations. The excess viscosities for all the systems are negative over the entire compositions. There are specific interactions between 1,2-dichloroethane and chlorinated methanes, but the specific interactions are not strong. The interactions of 1,2-dichloroethane with chlorinated methanes decrease in the order: chloroform > dichloromethane > carbon tetrachloride. ‘Pseudochloroform’ has been defined by us for the first time as the equimolar mixture of dichloromethane and carbon tetrachloride.  相似文献   

16.
Densities are reported for N,N-dimethylformamide and 1,2-dimethoxyethane binary mixtures at different mole fractions covering the whole miscibility range and at 19 temperatures ranging from –10 to 80°C. The experimental density data have been fitted by empirical relations and the excess volumes by a Redlich-Kister equation. The 11 N,N-dimethylformamide and 1,2-dimethoxyethane adduct appears to be stable throughout the temperature range. A comparison with other DMF containing mixtures is made.  相似文献   

17.
Excess properties calculated from literature values of experimental density and viscosity in N,N-dimethylformamide (DMF) + methanol (Met) binary mixtures (from 303.15 to 323.15 K) can lead us to test different correlation equations as well as their corresponding derivative properties. Inspection of the Arrhenius activation energy (Ea) and the enthalpy (ΔH*) of activation of viscous flow shows very close values; here, we can define partial molar activation energies Ea1 and Ea2 for N,N-DMF and Met, respectively, along with their individual contribution separately. Correlation between the two Arrhenius parameters of viscosity in all compositions shows existence of main distinct interaction behaviours delimited by particular mole fractions in N,N-DMF. In addition, we add that correlation between Arrhenius parameters reveals interesting Arrhenius temperature that is closely related to the vaporisation temperature in the liquid vapour equilibrium, and the limiting corresponding partial molar properties can permit us to estimate the boiling points of the pure components.  相似文献   

18.
Excess molar enthalpies, HmE, of binary mixtures containing poly(ethylene glycol) (PEG) 200+1,3-dioxolane, PEG 200+1,4-dioxane, PEG 200+oxolane and PEG 200+oxane were determined using a flow microcalorimeter at (288.15, 298.15 and 313.15) K and at atmospheric pressure. The HmE curves are always positive, with maxima varying from 393 J mol−1 (1,3-dioxolane) to 658 J mol−1 (oxolane), showing asymmetrical trends. The effect of the temperature is well marked on the calorimetric data that increase as the temperature is increased. The Redlich-Kister polynomial was used to estimate the binary fitting parameters. Root-mean-square deviations from the regression lines are reported.  相似文献   

19.
20.
Volume changes on mixing for the binary systems formed by chlorobenzene with 1,2-dichloroethane, 1,1,1-trichloroethane and 1,1,2,2-tetrachloroethane, and by bromobenzene with 1,2-dichloroethane, 1,1,1-trichloroethane and 1,1,2,2-tetrachloroethane, have been measured as functions of composition at 303.15 and 313.15 K. The measured excess volumes are positive over the entire range of composition for the binary systems chlorobenzene + 1,2-dichloroethane and bromobenzene + 1,2-dichloroethane at 303.15 K, and for chlorobenzene + 1,1,2,2-tetrachloroethane at 313.15 K. The measured volumes VE are negative over the entire composition range for the remaining systems, except for the system chlorobenzene + 1,1,2,2-tetrachloroethane at 303.15 K, where an inversion of the sign of VE is observed over part of the concentration range.  相似文献   

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