Equilibres liquide-vapeur isothermes de melanges binaires de la piperidine et de la N-methyl piperidine avec certains ethers

The authors have measured the vapour pressure of the four binary systems, piperidine +tert-butyl methyl ether, piperidine +1,4 dioxane, piperidine + tetrahydropyrane and N-methyl piperidine +tert-butyl methyl ether. The measurements were carried out using an isoteniscope built by J. Jose [1], The vapour pressure, excess Gibbs free energies at 298.15, 303.15, 313.15, 323.15, 333.15 and 343.15 K, are reported for these mixtures. The excess Gibbs free energies have been fitted to the Redlich-Kister equation.

     

Equilibres liquide-vapeur isothermes de melanges binaires de la piperidine et de la N-methyl piperidine avec certains ethers

The authors have measured the vapour pressure of the binary four systems, piperidin +1,4-dioxan, piperidin+tetrahydropyran, piperidin+tert-butyl methyl ether and N-methyl piperidin+tert-butyl methyl ether. The measurements were carried out using an isoteniscope built by J. Jose [1]. The vapour pressure, excess Gibbs free energies at 298.15 K, 303.15 K, 313.15 K, 323.15 K, 333.15 K and 343.15 K, are reported for these mixtures. The excess Gibbs free energies have been fitted to the Redlich-Kister equation.     

Equilibres liquide-vapeur isothermes de melanges binaires formes de composes heterocycliques tels que: Morpholine,tetrahydropyranne, piperidine et 1,4-dioxane

The authors have measured the vapour pressure of four binary systems, morpholine+piperidine, morpholine+1,4-dioxane, morpholine+tetrahydropyrane and 1,4-dioxane+tetrahydropyrane. The measurements were carried out using an isoteniscope built by J. Jose [1]. The vapour pressure, excess Gibbs free energies at 298.15, 303.15, 313.15, 323.15, 333.15 and 343.15 K are reported for these mixtures. The excess Gibbs free energies have been fitted to the Redlich-Kister equation.     

Thermodynamic properties of binary mixtures containing n-alkylamines: I. Isothermal vapour–liquid equilibrium and excess molar enthalpy of n-alkylamine+toluene mixtures. Measurement and analysis in terms of group contributions

Molar excess enthalpies, H^E, at 303.15 K and atmospheric pressure, of n-propyl-, n-butyl-, n-pentyl-, n-octyl- or n-decylamine+toluene, as well as the isothermal vapour–liquid equilibria, VLE, of n-butylamine+toluene and of n-butylamine+benzene at 298.15 K have been determined. These experimental results, along with the data available in the literature on molar excess Gibbs energies, G^E, activity coefficients at infinite dilution, γ_i^∞, and molar excess enthalpies, H^E, for n-alkylamine+toluene mixtures are examined on the basis of the DISQUAC group contribution model. The modified UNIFAC is also used to describe the mixtures.     

Thermodynamic properties of binary mixtures containing n-alkylamines: II. Isothermal vapour–liquid equilibrium and excess molar enthalpy of n-alkylamine+ethylbenzene mixtures. Measurement and analysis in terms of group contributions

Molar excess enthalpies, H^E, at 303.15 K and atmospheric pressure, of n-propyl-, n-butyl-, n-pentyl-, n-octyl- or n-decylamine+ethylbenzene, as well as the isothermal vapour–liquid equilibrium (VLE) of n-butylamine+ethylbenzene at 298.15 K have been determined. These experimental results, along with the data available in the literature on molar excess Gibbs energies, G^E, for n-alkylamine+ethylbenzene mixtures are examined on the basis of the DISQUAC group contribution model. The modified (mod.) UNIFAC is also used to describe the mixtures.     

Excess Gibbs free energies and excess enthalpies for triethylamine + n-hexane,triethylamine + n-octane,and tributylamine + n-hexane at 298.15 K

Total vapour pressures have been measured by the isoteniscope method for triethylamine + n-hexane, triethylamine + n-octane, and tributylamine + n-hexane at 298.15 K. The excess Gibbs free energies G^E for the liquid phase have been calculated from the measurements; G^E is positive for the triethylamine systems and negative for the tributylamine system. The excess enthalpies H^E for these three mixtures and for tributylamine + n-octane have been measured at the same temperature. Except for tributylamine + n-hexane, all these H^E's are positive.     

Viscosities and Densities of Solutions of n-Decane, or n-Tetradecane with Several Esters at 25°C

Viscosity and density data are reported for n-decane + propyl ethanoate, propyl propanoate, propyl butyrate, and n-tetradecane + propyl ethanoate, propyl propanoate, and propyl butyrate at 25°C and atmospheric pressure. Kinematic viscosities were determined using a capillary viscosimeter and densities were measured using vibrating-tube densimetry. The equations of Grunberg–Nissan, McAllister, Auslander, and Teja were fitted to the viscosity data. Excess molar Gibbs free energies of activation for flow were also evaluated. The experimental values obtained for excess volumes were compared with the Nitta et al. group contribution model.     

Thermodynamics of Organic Mixtures Containing Amines. II. Excess Molar Volumes at 25°C for Methylbutylamine + Alkane Systems and Eras Characterization of Linear Secondary Amine + Alkane Mixtures

Excess molar volumes, at 25°C and atmospheric pressure for methylbutyl amine + n-hexane; + cyclohexane; + n-octane; n-decane; + n-dodecane; + n-tetradecane, or + n-hexadecane systems are reported from densities measured with a vibrating-tube densimeter. The excess functions, molar enthalpy, and volume, for linear secondary amine + n-alkane systems are discussed in terms of interactional and structural effects. In addition, these solutions, which include amines from dimethyl to dioctylamine, are studied in the framework of the ERAS model. The corresponding ERAS parameters are reported. The agreement between experimental data and ERAS results is good for excess enthalpies, excess Gibbs energies, and excess molar volumes. The larger discrepancies are found for the excess volumes when strong free-volume effects are present in the investigated mixtures. The variation with temperature of the thermodynamic properties is well described by ERAS.     

Densities and Viscosities of the Binary Mixtures Decanol + Some n-Alkanes at 298.15 K

Abstract

Densities and viscosities of four binary liquid systems decanol +n-heptane, +n-octane, +n-nonane, +n-decane, have been determined at 298.15 K and atomospheric pressure, over the complete composition ranges. The excess values of molar volume, viscosity and Gibbs free energy for the activation of flow were evaluated. The Grunberg-Nissan parameter was also calculated. The viscosity data were fitted to the equations of McAllister and Auslander.     

Excess thermodynamic properties and vapor-liquid equilibrium data for then-butylamine+p-dioxane system at 25°C

Excess values of molar volumes, viscosities, molar enthalpies, Gibbs molar energies, surface tensions and molar diamagnetic susceptibilities were calculated at 25°C for then-butylamine+p-dioxane system. The observed deviations from the ideality were explained on the basis of intermolecular interactions. Van Laar's equations were the best in predicting activity coefficients for this system.     

Refractive Properties of Binary Mixtures Containing 2-Methoxyethanol and n-Butylamine,Isobutylamine, sec-Butylamine and tert-Butylamine

Refractive index (n) and related properties such as molar refraction (R) have been investigated for 2-methoxyethanol (ME) + n-butylamine (n-BA) and 2-methoxyethanol (ME) + isobutylamine (iso-BA), 2-methoxyethanol (ME) + sec-butylamine (sec-BA) and 2-methoxyethanol (ME) + tert-butylamine (tert-BA) binary mixtures over the entire composition range, at different temperatures in the range 291.15 ≤? T/K ≤? 313.15. Furthermore, the excess molar refraction (R^E ) and deviation from ideality refractive index (Δn) have been examined, in order to identify the presence of intermolecular complexes in these binary liquid mixtures. The results obtained have been interpreted on the basis of specific intermolecular interactions between species.     

The kinetics of proton transfer from octaphenylsubstituted tetraazaporphyrin to organic bases in benzene

The acid-base interaction of octa(m-trifluoromethylphenyl)tetraazaporphin with pyridine, 2-methylpiridine, morpholine, benzylamine, piperidine, n-butylamine, diethylamine, tert-butylamine, and triethylamine in benzene was studied. It was found that intermolecular transfer of spatially screened NH-group protons from octa(m-trifluoromethylphenyl)tetraazaporphin to morpholine, benzylamine, piperidine, n-butylamine, and tert-butylamine is characterized by unusually low values of rate constants. The effect of the structure of octa(m-trifluoromethylphenyl)tetraazaporphin, octa(n-bromophenyl)tetraazaporphin, octa(n-bromophenyl)tetraazaporphin, and octa(n-nitrophenyl)tetraazaporphin, and the nature of a base on the kinetic parameters of acid-base equilibrium is shown. A structure for complexes with proton transfer of octaphenylsubstituted tetraazaporphirins is suggested. It is revealed that they are subject to decomposition over time with the formation of low molecular colorless products.     

Activity Coefficient and Excess Gibbs Free Energies of Propargyl Alcohol with Trichloroethylene

Abstract

Isobaric vapour-liquid equilibrium data are measured at 200, 500 and 707 mm Hg at ten compositions spread evenly over the entire liquid mole fraction range, employing a Swietoslawski type ebulliometer. The liquid phase composition vs. bubble temperature (x-t) data are found to be well represented by Wilson model The optimum Wilson parameters are used to calculate the vapour phase compositions, activity coefficients and the excess Gibbs free energies.     

Thermodynamics of binary mixtures with n-mono and n-dibutyl phosphates

Thermodynamic properties of the binary mixtures of n-monobutyl phosphate and n-dibutyl phosphate with a number of diluents (water, benzene, hexane, cyclohexane, carbon tetrachloride, chloroform and ethanol) are considered. They were evaluated from the total vapour pressure measurements performed in the temperature range, 298.15–318.15 K. Activity coefficients and the excess Gibbs energies of mixing were calculated from the Gibbs-Duhem equation and the results obtained are discussed in terms of intermolecular hydrogen bond formation.     

Excess Molar Volumes of Aqueous Solutions of Butylamine Isomers

Abstract

Excess molar volumes (V^E ) and average thermal expansivities (α) of the systems, water (W) + n-butylamine (NBA), W + sec-butylamine (SBA), and W + tert-butylamine (TBA), have been calculated from the density data at temperatures ranging from 298.15–323.15 K. The V^E and α values have been plotted as functions of mole fraction of amines. The systems show large negative excess volumes, magnitude of which varies in the order, W + TBA > W + SBA > W + NBA. The curves are found to be symmetrical along the composition axis, with minima occurring at 0.5 mole fraction of butylamines. The negative excess volumes have been interpreted primarily by two effects: (i) strong chemical interaction leading to the formation of 1:1 complexes through H-bonding and (ii) hydrophobic hydration causing significant contraction of volume.     

Thermodynamics of binary mixtures: excess gibbs free energies of 1,2-Dibromoethane mixtures with benzene,cyclohexane, carbon tetrachloride and dioxane at 20°C

The excess Gibbs free energies of 1,2-dibromoethane mixtures with benzene, cyclohexane, carbon tetrachloride and dioxane have been determined by a static vapour pressure method at 20°C. The results have been analysed in the light of the current theories of solutions due to Prigogine and Flory. Both the theories fail to fit the results with useful accuracy.     

Thermodynamic activation parameters for viscous flow of aqueous solutions of butylamines

The thermodynamic activation parameters, enthalpies, ΔH?^≠, free energies, ΔG ^≠, and entropies, ΔS?^≠, for viscous flow of the systems, water (W)?+?n-butylamine (NBA), W?+?sec-butylamine (SBA) and W?+?tert-butylamine (TBA), have been determined by using the density and the viscosity data. These properties and their excess values have been represented graphically against their composition. With respect to the composition, ΔG ^≠ show a typical behaviour for all the systems – a fast rise in the water-rich region with a maximum followed by the values that decline up to the pure state of amines. The ΔH?^≠ and ΔS?^≠ versus composition curves follow the similar trend. For all systems the excess properties, ΔG ^≠E, ΔH ^?≠E and ΔS?^≠E are characterized by sharp maxima in the water-rich region, which are thought to be mainly due to the hydrophobic hydration and the hydrophilic effect.     

Studies of viscosity and excess molar volume of binary mixtures: 4. 1-Alkanol + tri-n-butylamine mixtures at 303.15 and 313.15 K

The excess molar volume V^E, the viscosity deviation Δη and the excess Gibbs energy of activation ΔG^1E of viscous flow are calculated from density and viscosity measurements of six mixtures of 1-propanol, 1-butanol, 1-pentanol, 1-heptanol, 1-octanol and 1-decanol with tri-n-butylamine over the entire range of mole fractions at 303.15 and 313.15 K. The values of V^E of all six systems are very large and negative. Except for 1-propanol+tri-n-butylamine, the magnitude of negative deviations in viscosity increases with chain length of alkanol. The results have been explained considering mixed associated species of type A_iB involving alkanol (A) with tri-n-butylamine (B) through OH⋯N bonds. The viscosity data have been correlated with the equations of Grunberg and Nissan, Tamura and Kurata, Hind, McLaughlin and Ubbelohde, Katti and Chaudhri, McAllister, Heric, and of Auslaender.     

Excess Gibbs free energies at several temperatures and excess enthalpies and volumes at 298.15 K of butanenitrile with 2-methyl-1-propanol or 2-methyl-2-propanol

Vapour pressures of butanenitrile +2-methyl-1-propanol or +2-methyl-2-propanol at several temperatures between 278.15 and 323.15 K were measured by a static method. Excess molar enthalpies and volumes were also measured at T = 298.15 K. Reduction of the vapour pressures to obtain activity coefficients and excess molar Gibbs free energies was carried out by fitting the vapour pressure data to the Redlich-Kister correlation according to Barker's method. Azeotropic mixtures with a minimum boiling temperature were observed over the whole temperature range, except for 2-methyl-2-propanol at T = 323.15 K.     

Thermodynamics of Viscous Flow of <Emphasis Type="Italic">tert</Emphasis>-Butanol with Butylamines: UNIFAC–VISCO,Grunberg–Nissan and McAllister Three Body Interaction Models for Viscosity Prediction and Quantum Chemical (DFT) Calculations

Thermodynamic activation parameters, enthalpies (ΔH ^?), entropies (ΔS ^?) and Gibbs energies (ΔG ^?) for viscous flow of the systems tert-butanol (TB)+n-butylamine (NBA), TB+di-n-butylamine (DBA) and TB+tri-n-butylamine (TBA) have been calculated from measured density and viscosity data at temperatures ranging from 303.l5 to 323.15 K over the composition range 0 ≤ x ₂ ≤ 1, where x ₂ is the mole fraction of TB. For all systems, the corresponding excess properties ΔH ^?E, ΔS ^?E and ΔG ^?E have been determined, which are negative in the whole range of composition. The observed negative excess activation properties have been accounted for in terms of dispersive forces and H-bonding. The derived properties are well represented by fourth degree polynomial equations whereas the excess properties could be fitted to third degree Redlich–Kister polynomial equations. Furthermore, the viscosities have been predicted by using the UNIFAC–VISCO model, Grunberg–Nissan model and McAllister three-body interaction model. The UNIFAC–VISCO model and Grunberg–Nissan model do not show good agreement with the experimental data, whereas the McAllister three-body interaction model shows excellent agreement for all three systems, with small average absolute percent deviations (AAD% = 0.6–2.3). The DFT-B3LYP method with the 6-311 G (d, p) basis set has been employed for the optimization of the geometry and calculation of the total energies of the pure compounds and their binary complexes.