Experimental excess molar volumes of the ternary mixture and comparisonwith several empirical methods

Experimental excess molar volumes for the ternary system {x₁MTBE+x₂1-propanol+(1–x₁–x₂)nonane} and the three involved binary mixtures have been determined at 298.15 K and atmospheric pressure. Excess molar volumes were determined from the densities of the pure liquids and mixtures, using a DMA 4500 Anton Paar densimeter. The ternary mixture shows maximum values around the binary mixture MTBE+nonane and minimum values for the mixture MTBE+propanol. The ternary contribution to the excess molar volume is negative, with the exception of a range located around the rich compositions of 1-propanol. Several empirical equations predicting ternary mixture properties from experimental binary mixtures have been applied.     

Determination of experimental excess molar properties for MTBE+1-propanol+octane

Summary Experimental excess molar enthalpies and densities have been measured for the ternary mixture x₁MTBE+x₂1-propanol+(1-x₁-x₂)octane and the involved binary mixtures at 298.15 K and atmospheric pressure. In addition, excess molar volumes were determined from the densities of the pure liquids and mixtures. A standard Calvet microcalorimeter was employed to determine the excess molar enthalpies. Densities were measured using a DMA 4500 Anton Paar densimeter. The UNIFAC group contribution model (in the versions of Larsen et al., and Gmehling et al.) has been used to estimate excess enthalpies values. Experimental data were also used to test several empirical expressions for estimating ternary properties from experimental binary results.     

Experimental and predicted excess molar volumes of the ternary system.

Summary Experimental excess molar volumes for the ternary system x₁MTBE+x₂1-propanol+(1-x₁-x₂) heptane and the three involved binary mixtures have been determined at 298.15 K and atmospheric pressure. Excess molar volumes were determined from the densities of the pure liquids and mixtures, using a DMA 4500 Anton Paar densimeter. The ternary mixture shows maximum values around the binary mixture MTBE+heptane and minimum values for the mixture MTBE+propanol. The ternary contribution to the excess molar volume is negative, with the exception of a range located around the rich compositions of 1-propanol. Several empirical equations predicting ternary mixture properties from experimental binary mixtures have been applied.     

Thermodynamic properties of the ternary system MTBE+1-propanol+hexane

Experimental excess molar enthalpies and excess molar volumes of the ternary system x₁MTBE+x₂1-propanol+(1-x₁-x₂) hexane and the involved binary mixtures have been determined at 298.15 K and atmospheric pressure. Excess molar enthalpies were measured using a standard Calvet microcalorimeter, and excess molar volumes were determined from the densities of the pure liquids and mixtures, using a DMA 4500 Anton Paar densimeter. The UNIFAC group contribution model (in the versions of Larsen et al., and Gmehling et al.) has been employed to estimate excess enthalpies values. Several empirical expressions for estimating ternary properties from experimental binary results were applied.     

Excess Molar Volumes and Excess Partial Molar Volumes of Triethylene Glycol Monoethyl Ether–n-Alcohol Mixtures at 25°C

We have measured excess molar volumes V^E _m of binary mixtures of triethylene glycol monoethyl ether with methanol, ethanol, 1-propanol, 1-pentanol, and 1-hexanol over the full range of compositions at 25°C. The measurements were carried out with a continuous-dilution dilatometer. The excess molar volumes V^E _m are negative over the entire range of composition for the systems triethylene glycol monoethyl ether + methanol, + ethanol, and + 1-propanol and positive for the remaining systems, triethylene glycol monoethyl ether + 1-pentanol, and + 1-hexanol. The excess V^E _m increases in the positive direction with increasing chain length of the n-alcohol. The measured excess volumes have been compared to our previous published data with an effort to assess the effects of replacing methyl by ethyl groups and of inserting oxyethylene groups. The results have been used to estimate the excess partial molar volumes V^E _m,i of the components. The behavior of V^E _m and V^E _m,i with composition and the number of carbon atoms in the alcohol molecule is discussed.     

Excess molar volumes of N,N-dimethylformamide + 2-pentanone + alkan-1-ols mixed solvent systems at 303.15 K

Accurate excess molar volumes (V^E), at ambient pressure and 303.15 K, have been determined in the ternary liquid mixtures of N,N-dimethylformamide (DMF) + 2-pentanone (PE) + 1-alkan-1-ols (C₃-C₆) and in the binary mixtures of PE + alkan-1-ols (C₃-C₆) as a function of composition. The alkanols include 1-propanol, 1-butanol, 1-pentanol and 1-hexanol. The intermolecular interactions and structural effects were analyzed on the basis of the measured and derived properties. Excess molar volumes increase in magnitude with increase in chain length of alcohol. Valuable information on the behavior and governing factors of the liquid structure of the strongly associated solvents studied were inferred from the parameters deduced. The V^E results were correlated and fitted by the Redlich-Kister equation for binary mixtures and by the Cibulka equation for ternary mixtures, as a function of mole fraction. Several predictive empirical relations were applied to predict the excess volumes of ternary mixtures from the binary mixing data. An analysis of the data indicates a good agreement between experimental results and predicted values in all ternary systems. A discussion is presented and deviations are interpreted in terms of size, shape, the position of ketone group, the chain length of alkanol and hydrogen bond effects in the liquid mixtures studied to explain chemical and thermophysical behavior.     

Study on volumetric measurement and correlations for MTBE+1-propanol+decane at 298.15 K and atmospheric pressure

Summary Experimental densities for the ternary mixture x₁MTBE+x₂1-propanol+(1-x₁-x₂)decane and the binary mixtures xMTBE +(1-x)1-propanol and x1-propanol+(1-x)decane have been measured at 298.15 K and atmospheric pressure, using a DMA 4500 Anton Paar densimeter. Excess molar volumes were determined from the densities of the pure liquids and mixtures. Attending to the symmetry of the studied mixtures, suitable fitting equations have been used in order to correlate adequately the experimental data. For the ternary mixture, experimental data were also used to test several empirical expressions for estimating ternary properties from experimental binary results.     

Densities and excess molar volumes of the binary system N-methyldiethanolamine + (2-aminoethyl)ethanolamine and its ternary aqueous mixtures from 283.15 to 363.15 K

Experimental density data of the binary mixtures of N-methyldiethanolamine + (2-aminoethyl)ethanolamine and the ternary mixtures of N-methyldiethanolamine + (2-aminoethyl)ethanolamine + water were reported at atmospheric pressure over the entire composition range at temperatures from 283.15 to 363.15 K. Density measurements were performed using an Anton Paar digital vibrating U-tube densimeter. Excess molar volumes were calculated from the experimental data and correlated as the Redlich-Kister equation for the binary mixtures, and as the Nagata-Tamura equation for the ternary mixtures. Several empirical models were applied to predict the excess molar volumes of ternary mixtures from the corresponding binary mixture values. It indicates that the best agreement with the experimental data was achieved by the Redlich-Kister, Kohler, and Jacob-Fitzner models.     

Ternary mixture MTBE+1-pentanol+nonane at 298.15 K and atmospheric pressure

Densities at 298.15 K and atmospheric pressure have been measured, using a DMA 4500 Anton Paar densimeter, for the ternary mixture methyl tert-butyl ether (MTBE)+1-pentanol+nonane and for the involved binary mixture 1-pentanol+nonane. In addition, excess molar volumes were determined from the densities of the pure liquids and mixtures. Suitable fitting equations have been used in order to correlate adequately the excess molar volumes. Experimental data were also used to test several empirical expressions for estimating ternary properties from experimental binary results.     

Densities and Viscosities of the Ternary Mixture (Benzene + 1-Propanol + Ethyl Acetate) at 298.15 K

Abstract

Densities and viscosities of the ternary mixture (benzene + 1-propanol + ethyl acetate) and the corresponding binary mixtures (benzene + 1-propanol, benzene + ethyl acetate and 1-propanol + ethyl acetate) have been measured at the temperature 298.15 K. From these measurements excess volumes, V^E , excess viscosities, η^E, and excess Gibbs energies of activation for viscous flow, G*^E , have been determined. The equation of Redlich-Kister has been used for fitting the excess properties of binary mixtures. The excess properties of the ternary system were fitted to Cibulka's equation.     

Thermodynamics of Mixtures with Strongly Negative Deviations from Raoult's Law. VII. Excess Molar Volumes at 25°C for 1-Alkanol + N-Methylbutylamine Systems—Characterization in Terms of the ERAS Model

Excess molar volumes, V ^E _m, at 25^°C and atmospheric pressure, over the entire composition range for binary mixtures of methanol, ethanol, 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, 1-heptanol, and 1-octanol with-methylbutylamine are reported. They are calculated from densities measured with a vibrating-tube densimeter. All the excess volumes are large and negative over the entire composition range. This indicates strong interactions between unlike molecules, which are greatest for the system involving methanol, characterized by the most negative V ^E _m. For the other solutions, V ^E _m at equimolar composition, is approximately the same. The V ^E _m curves vs. mole fraction are nearly symmetrical. The ERAS model is applied to 1-alkanol + N-methylbutylamine, and 1-alkanol + diethylamine systems. The ERAS parameters confirm that the strongest interactions between unlike molecules are encountered in solutions with methanol. The model consistently describes V ^E _m and excess molar enthalpies H ^E _m of the mixtures studied.     

Measurements and analysis of excess molar volumes for the ternary mixture MTBE + 1-pentanol + decane

Summary Densities at 298.15 K and atmospheric pressure have been measured, using a DMA 4500 Anton Paar densimeter, for the ternary mixture methyl tert-butyl ether (MTBE)+1-pentanol+decane and for the involved binary mixtures MTBE+1-pentanol and 1-pentanol+decane. The excess molar volumes for the binary mixture MTBE+decane was reported in an earlier work [1]. In addition, excess molar volumes were determined from the densities of the pure liquids and mixtures. Suitable fitting equations have been used in order to correlate adequately the excess molar volumes. The empirical expressions of Kohler [18], Jacob and Fitzner [19], Colinet [20], Knobeloch and Schwartz [21], Tsao and Smith [22], Toop [23], Scatchard et al. [24], Hillert [25], Mathieson and Thynne [26] were applied to estimate ternary properties from binary results.     

Excess molar volumes of methylcyclohexane+benzene, +methylbenzene, +1,4-dioxane,and +tetrahydrofuran at 303.15 K

Excess molar volumes V_m^E as function of mole fraction x for methylcyclohexane + benzene, + methylbenzene, + 1,4-dioxane, and + tetrahydrofuran are reported at 303.15 K. The excess molar volumes are positive and indicate the presence of weak interactions.     

Measurement of Some Thermodynamic and Acoustic Properties of Binary Solutions of N,N-Dimethylformamide with 1-Alkanols at 30°C and Comparison with Theories

Densities, and ultrasonic velocities, uof binary mixtures of N,N-dimethylformamide (DMF) + methanol, + ethanol, + 1-propanol, + 1-butanol, + 1-pentanol, and + 1-hexanol have been measured at 30°C. The ultrasonic velocities have been compared with values calculated from the free-length theory ( FLT) due to Jacobson and collision-factor theory ( CFT) due to Schaaffs. The measured data are used to compute adiabatic compressibility (k _s), deviation in adiabatic compressibility (k _s), intermolecular free length (L _f), molar volume (V _m), and available volume (V _a). The excess molar volume ( V _m ^E) and excess free length (L _f ^E) are also evaluated. For all systems, these results were satisfactorily correlated by the Redlich–Kister polynomial. These parameters are used to discuss dissociation of the self-associated 1-alkanol molecules and the formation of aggregates between unlike molecules through C=O...H–O hydrogen bonding.     

P-Vm-x Properties of Water-Dimethylformamide Mixtures at 278.15 K and Pressures of up to 100 MPa

The compressibility coefficients k = (v ₀ - v)/v ₀ of water-dimethylformamide (DMF) binary mixtures in the entire composition range at 278.15 K and pressures of up to 100 MPa were measured with a constant-volume piesometer. From the measured densities at atmospheric pressure and the coefficients k, the following quantities were calculated: specific and molar volumes of water-DMF mixtures at the examined parameters of state, excess molar volumes, partial molar volumes of the components, and variation with external pressure of the excess Gibbs energy of the water-DMF system. At all the pressures, the dependence k = f(x) (where x is the mole fraction of DMF in the mixture) passes through a minimum at x 0.2. The composition dependence of the specific volume of water-DMF mixtures also shows extrema, and its shape depends on the pressure. The partial molar volume of water at infinite dilution in DMF slightly depends on pressure.     

Excess Gibbs energies of the ternary system ethanol+N,N-dimethylformamide+cyclohexane at 298.15 K

Vapour–liquid equilibrium (VLE) for the ternary system ethanol (EtOH)+N,N-dimethylformamide (DMF)+cyclohexane (Cy) and for the relevant binary mixtures containing DMF have been determined at 298.15 K by headspace gas chromatographic analysis of the vapour phase directly withdrawn from an equilibrium apparatus. Measurements of liquid–liquid equilibria in both binary DMF+Cy and ternary mixtures have been also carried out. The binary VLE data have been described with different correlation equations. The capabilities of different models of either predicting or reproducing the ternary data have been compared. Excess Gibbs energies G^E as well as activity coefficients γ_i of components have been obtained and briefly discussed. While EtOH+DMF behaves almost ideally with slightly negative G^E-values, both EtOH+Cy and DMF+Cy exhibit large positive deviations. The G^Es of the ternary system are positive with the exception of a narrow region in dilute Cy. The excess entropy and the temperature dependence of G^E and γ_i have been calculated in the whole ternary domain from the known excess enthalpy and heat capacity. The predictions by different equations of the effect of temperature on the mutual solubilities of DMF and Cy as well as on the binodal curve of EtOH+DMF+Cy have been compared with experiment.     

Volumetric Properties of the Binary System Trihexyltetradecylphosphonium Bromide (CYPHOS IL 102) + N,N-Dimethylformamide (DMF) at Temperatures from T=293.15 to 313.15 K at Atmospheric Pressure

Volumetric properties for the trihexyltetradecylphosphonium bromide (CYPHOS IL 102) + N,N-dimethylformamide (DMF) binary system were determined at temperatures from T=293.15 to 313.15?K and ambient pressure (p=0.7 atm). Densities were measured by means of a vibrating tube densimeter (VTD). These measurements covered the full range of compositions along with the pure compounds; expansion coefficients, excess molar volumes, and partial molar volumes were calculated from the experimental densities. Excess molar volumes were fitted to a Redlich?CKister type equation. The excess molar volumes exhibit negative deviations from ideal behavior.     

Thermodynamics of mixtures with strongly negative deviations from Raoult’s law: Part 6. Excess molar volumes at 298.15 K for 1-alkanols + dibutylamine systems. Characterization in terms of the ERAS model

Excess molar volumes, V_m^E, at 298.15 K and atmospheric pressure over the entire composition range for binary mixtures of methanol, ethanol, 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, 1-heptanol and 1-octanol with dibutylamine are reported. They are calculated from densities measured with a vibrating-tube densimeter. All the excess volumes are large and negative over the whole mole fraction range, indicating strong interactions between unlike molecules, which are more important for the systems involving methanol or ethanol, characterized by the most negative V_m^E. For the other mixtures, V_m^E at equimolar composition, is approximately constant. The V_m^E curves are nearly symmetrical. The V_m^E and excess molar enthalpies (H_m^E) of the mixtures studied are consistently described by the ERAS model. The ERAS parameters confirm that the strongest interactions between unlike molecules are encountered in the methanol+dibutylamine system.     

A Polarographic Study of Tl + , Pb 2 and Cd 2+ Complexes with Dicyclohexano-18-Crown-6 in Some Binary Mixed Solvents

The complexes of Tl⁺, Pb²⁺ and Cd²⁺ cations with the macrocyclic ligand, dicyclohexano-18-crown-6\linebreak(DC18C6) were studied in water/methanol (H₂₊O/MeOH), water/1-propanol (H₂₊O/1-PrOH), water/acetonitrile (H₂₊O/AN), water/dimethylformamide (H₂₊O/DMF), dimethylformamide/acetonitrile (DMF/AN), dimethylformamide/methanol (DMF/MeOH), dimethylformamide/1-propanol (DMF/1-PrOH) and dimethylformamide/nitromethane (DMF/NM) mixed solvents at 22 °C using differential pulse polarography (DPP), square wave polarography and conductometry. In general, the stability of the complexes was found to decrease with increasing concentration of water in aqueous/non-aqueous mixed solvents with an inverse relationship between the stability constants of the complexes and the concentration of DMF in non-aqueous mixed solvents. The results show that the change in stability of DC18C6.Tl⁺, vs the composition of solvent in DMF/AN and DMF/NM mixed solvents is apparently different from that in DMF/MeOH and DMF/1-PrOH mixed solvents. While the variation of stability constants of the DC18C6.Tl⁺ and DC18C6.Pb²⁺ complexes vs the composition of H₂₊O/AN mixed solvents is monotonic, an anomalous behavior was observed for variations of log K_f vs the composition of H₂₊O/1-PrOH and H₂₊O/MeOH mixed solvents. The selectivity order of the DC18C6 ligand for the cations was found to be Pb²⁺ > Tl⁺ > Cd²⁺.     

Densities and Excess Molar Volumes of Binary and Ternary Mixtures of Aqueous Solutions of 2,2,2-Trifluoroethanol with Acetone and Alcohols at the Temperature of 298.15 K and Pressure of 101 kPa

Excess molar volumes V_m^E of the binary mixtures of (trifluoroethanol + 1-propanol), (trifluoroethanol + 2-propanol), (acetone + water), (methanol + water), (ethanol + water), (1-propanol + water), (2-propanol + water), and the ternary mixtures of (trifluoroethanol + methanol + water), (trifluoroethanol + ethanol + water), (trifluoroethanol~+ 1-propanol + water), (trifluoroethanol + 2-propanol + water) and (trifluoroethanol + acetone + water) were measured with a vibrating tube densimeter at the temperature of 298.15 K and the pressure 101 kPa. The extrema in V_m^E of trifluoroethanol mixtures occur at –0.690 cm³-mol^–1 for (trifluoroethanol + 1-propanol), at –0.990~cm³-mol^–1 for (trifluoroethanol + 2-propanol); at 0.562 and –0.973 cm³-mol^–1 for (trifluoroethanol + methanol + water), at 0.629 and –0.973 cm³-mol^–1 for (trifluoroethanol + ethanol + water), at 1.082 and –0.659 cm³-mol^–1 for (trifluoroethanol~+ 1-propanol + water), at 0.998 and –0.991 cm³-mol^–1 for (trifluoroethanol~+ 2-propanol + water), and at 0.515 and –1.472 cm³-mol^–1 for (trifluoroethanol + acetone + water). The experimental ternary V_m^E values were predicted by empirical expressions using binary solution data.