Volumetric study of (diethylamine + water) mixtures between (278.15 and 308.15) K

Densities have been measured for aqueous mixtures of diethylamine at the temperatures: (278.15, 288.15, 293.15, 298.15, and 308.15) K, for the entire composition range. The data have been used to calculate apparent molar, excess molar and excess partial molar volumes. Limiting values of excess partial molar volumes and expansions have been derived as well. The discussion has been undertaken comparing the obtained values with those of parent studies in related compounds.     

Properties of L-ascorbic acid in water and binary aqueous mixtures of D-glucose and D-fructose at different temperatures

Using density and sound velocity partial molar volumes, partial molar adiabatic compressibilities, partial molar expansibilities and structure of L-ascorbic acid have been determined in water and aqueous mixtures of D-glucose and D-fructose at different concentrations and temperatures. Masson’s equation was used to analyze the measured data. The obtained parameters have been interpreted in terms of solute–solute and solute–solvent interactions. It is found that the L-ascorbic acid acts as structure breaker in water as well in binary studied mixtures.     

Thermophysical properties of binary mixtures of {ionic liquid 2-hydroxy ethylammonium acetate + (water,methanol, or ethanol)}

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.     

Volumetric Properties for Binary and Ternary Mixtures Containing Benzyl Alcohol,Ethyl Butyrate and Diethyl Malonate at <Emphasis Type="Italic">T</Emphasis> = (293.15–313.15) K and <Emphasis Type="Italic">p</Emphasis> = 0.087 MPa

The densities of binary and ternary mixtures of benzyl alcohol + ethyl butyrate and/or diethyl malonate were measured at T = (293.15–313.15) K and p = 0.087 MPa. From these data, the excess molar volumes, partial molar volumes, excess partial molar volumes, partial molar volumes at infinite dilution, thermal expansion coefficients and their excess values were calculated. The Redlich–Kister equations were fitted to the excess molar volumes data. The results show that the excess molar volumes for all considered binary and ternary systems are negative and decrease with increasing temperature. The same behavior was observed for the excess thermal expansion coefficients. Data for excess volumes in ternary system were fitted with the Nagata–Tamura and Cibulka models for which the Cibulka equation showed better fitting. The intermolecular interactions between molecules in these mixtures are discussed and explained based on these experimental data.     

Volumetric properties of binary mixtures of N-ethylformamide with tetrahydrofuran, 2-butanone,and ethylacetate from T = (293.15 to 313.15) K

Densities of binary liquid mixtures of N-ethylformamide (NEF) with tetrahydrofuran (THF), 2-butanone (B), and ethylacetate (EA) were measured at temperatures from (293.15 to 313.15) K and at atmospheric pressure over the whole composition range. Excess molar volumes, V^E, have been obtained from values of the experimental density and were fitted to the Redlich–Kister polynomial equation. The V^E values for all three mixtures are negative over the entire composition and temperature ranges. The V^E values become more negative as the temperature increases for all binary mixtures studied. Other volumetric properties, such as isobaric thermal expansion coefficients, partial molar volumes, apparent molar volumes, partial molar excess volumes and excess thermal expansions have been calculated.     

The bulk properties of ethylene glycol-dimethylsulfoxide mixtures over the temperature range 278–323 K at <Emphasis Type="Italic">p</Emphasis> = 0.1 MPa

The densities of ethylene glycol-dimethylsulfoxide binary mixtures were measured over the temperature range 278–323.15 K at atmospheric pressure using a vibrational densimeter. The excess molar volumes, apparent molar volumes, partial molar volumes of mixture components, volumetric thermal expansion coefficients, and partial molar volumetric thermal expansion coefficients were calculated. The excess molar volumes were described by the Redlich-Kister equation, and the partial molar volumes were calculated by two methods. The density-composition dependence contained a weak maximum, which disappeared as the temperature increased. The excess molar volumes were negative, and deviations from ideality increased as the temperature grew.     

Transfer Volumes of Glycine, L-Alanine and L-Serine in Glycerol-Water Mixtures at 25°C

Densities of solutions of glycine, L-alanine, and L-serine have been measured by an oscillating-tube densimeter at 25^°C in glycerol–water mixtures with glycerol mass fractions ranging from 0 to 0.50. Apparent molar volumes and limiting partial molar volumes of each amino acid have been calculated. The trends of transfer volumes have been interpreted by the cosphere overlap model. The results show that the presence of glycerol in water decreases the electrostriction caused by the amino acid zwitterion.     

Volume behavior of mixed micelles of dodecyltrimethylammonium chloride and bromide

Densities of aqueous solutions of mixtures of dodecyltrimethylammonium chloride (DTAC) and dodecyltrimethylammonium bromide (DTAB) have been measured as a function of total molality at constant composition and the apparent molar volumes of the mixtures were derived from the density data. The partial molar volumes of monomeric surfactant mixtures, the molar volumes of mixed micelles, and the volumes of formation of mixed micelles were evaluated and are compared with those for decyltrimethylammonium bromide (DeTAB) and DTAB mixtures. The partial molar volumes of monomeric surfactant mixtures and the molar volumes of mixed micelles are observed to depend linearly on the monomer and micelle compositions, respectively. Although the volume of formation of mixed micelles of the DeTAB-DTAB mixture depends on the micellar composition, that of the DTAC-DTAB mixture is observed to be almost independent of the micellar composition. This suggests that the volumes of the counter ions in the micellar solutions are almost equal to those in the monomeric solutions.     

Volumetric properties of (piperidine + water) binary system: Measurements and modeling

Densities of pure piperidine (CAS No.: 110-89-4) and of its mixtures with water have been measured over the whole range of compositions at temperatures from 283.15 K to 347.15 K using Anton Paar? digital vibrating tube densimeter. The density of this system has been found increasing with mass fraction of water. Excess molar volumes have been calculated using the measured experimental densities and correlated using the Redlich–Kister equation. Redlich–Kister equation parameters have been adjusted on experimental data. In addition, partial molar volumes and partial excess molar volumes at infinite dilution have been calculated for each component.     

Determination of the excess molar and partial molar volumes of the constituents in the binary mixtures with tri-ethylamine

The excess molar volume and excess partial molar volumes of binary mixtures of tri-ethylamine with toluene (Tn), ethylbenzene (Ebz) and n-propylbenzene (n-PBz) have been calculated using the MS-Excel method. The excess molar volumes have been found to be negative throughout the entire range of composition. The temperature effects are found to be insignificant, so the mixtures may be termed regular mixtures of Hildebrand.     

Volumetric behavior of water–methanol mixtures in the vicinity of the critical region

Densities of water–methanol mixtures at 573 and 588 K and at pressures in the 100–200 bar range have been measured with a vibrating-tube densimeter. Temperature and pressure dependence of the excess molar volumes together with the previous results was discussed. A large negative-to-positive sigmoidal change of the excess molar volumes as a function of methanol mole fraction was interpreted on the basis of an estimated critical locus of the mixtures. The volumetric behavior of the mixtures was compared with that of the previously reported water–benzene mixtures by estimating the relative volume change on mixing. A large negative volume change at the lower methanol concentrations is in sharp contrast to the large positive change for the water–benzene mixtures. This contrast may be attributable to characteristic features of aqueous solutions of hydrophilic and hydrophobic substances in the vicinity of the critical region. The behavior of the water–methanol mixtures at the lower methanol mole fractions was discussed in terms of the local solute–solvent structure by estimating radial distribution functions and self-diffusion coefficients from molecular dynamics calculations.     

Excess Molar Enthalpies of Cyclic Ethers with Cyclohexane, Methylcyclohexane, or Chlorocyclohexane

Excess molar enthalpies for mixtures of tetrahydrofuran, tetrahydropyran, 2-methyltetrahydrofuran or 2,5-dimethyltetrahydrofuran with cyclohexane, methylcyclohexane, or chlorocyclohexane were determined at 25°C. The excess enthalpies are positive for the mixtures containing cyclohexane or methylcyclohexane, but negative for the mixtures containing chlorocyclohexane. The results were used with the Prigogine–Flory–Patterson theory to predict the corresponding excess molar volumes.     

Experimental molar volumes for some LNG-related saturated liquid mixtures

Miller, R.C. and Hiza, M.J., 1978. Experimental molar volumes for some LNG-related saturated liquid mixtures. Fluid Phase Equilibria, 2: 49–57.Saturated (orthobaric) liquid molar volumes are reported for some methane-rich mixtures containing ethane, propane, isobutane, normal butane and nitrogen at temperatures between 100 and 115 K. These data were obtained with a gas-expansion system calibrated against pure methane orthobaric liquid molar volumes. Comparisons are shown between the experimental molar volumes and the results of some recent calculational methods. Discrepancies between experimental and calculated values are all within ± 0.15 percent. The more accurate correlations generally predict the molar volumes within ± 0.1 percent.     

Volumetric properties of the glycerol formal + water cosolvent system and correlation with the Jouyban–Acree model

Excess molar volumes and partial molar volumes were investigated from density measurements for glycerol formal?+?water mixtures at temperatures from 278.15 to 313.15?K. Excess molar volumes are fitted using Redlich–Kister equation and compared with literature values for other systems. The system exhibits negative excess volumes, probably due to increased interactions like hydrogen bonding or large differences in molar volumes of components. The effect of temperature on different volumetric properties studied is also analysed. Besides, the volume thermal expansion coefficients are also calculated as 2.51?×?10^?4?K^?1 for water and 7.24?×?10^?4?K^?1 for glycerol formal at 298.15?K. Finally, the Jouyban–Acree model was used for density and molar volume correlations of the studied mixtures at different temperatures. The mean relative deviations between experimental and calculated data were 0.24?±?0.14% and 0.71?±?0.62%, respectively, for density and molar volume data.     

Influence of temperature on excess molar volumes for butyl acetate + aromatic hydrocarbons

Excess molar volumes dependence with temperature for the mixtures butyl acetate?+?aromatic hydrocarbons (toluene, ethylbenzene, p-xylene, mesitylene, isopropylbenzene, butylbenzene, isobutylbenzene, and t-butylbenzene) were determined from density measurements by a vibrating-tube densimeter. The excess molar volumes are positive or slightly negative in the studied mixtures over the whole composition range, attending to the solvent molecular weight, only the isobutylbenzene showing a sigmoid trend. Steric hindrance in these mixtures was analyzed in the light of partial excess molar volumes behavior. The experimental data were used to test semiempirical procedures of density prediction, and compute the binary interaction parameters of the Soave–Redlich–Kwong (SRK) and Peng–Robinson (PR) equations of state, which are of general interest in multicomponent thermodynamic functions estimation. The obtained results point out the interest of the equations of state to study complex mixtures and as a tool for predicting other magnitudes of general application for theoretical studies or processes calculations.     

Volumetric properties of {PEG 200 (or 300) (1) + water (2)} mixtures at several temperatures and correlation with the Jouyban–Acree model

Molar volumes and excess molar volumes were investigated from density values for {PEG 200 (1) + water (2)} and {PEG 300 (1) + water (2)} binary mixtures at temperatures from 278.15 to 313.15 K. Both systems exhibit negative excess volumes probably due to increased interactions such as hydrogen bonding and/or large differences in molar volumes of components. Volume thermal expansion coefficients were also calculated for both binary mixtures and pure solvents. The Jouyban–Acree model was used for density and molar volume correlations of the studied mixtures at different temperatures. The mean relative deviations between experimental and calculated density data were 0.02% and 0.04%, for aqueous mixtures of PEG 200 and PEG 300, respectively; whereas the corresponding values for molar volume data were 1.76% and 2.72%.     

Volumes and heat capacities of mixtures of dimethylformamide with several dialkylacetamides

Densities and heat capacities per unit volume of binary mixtures of dimethylformamide and a series of di-n-alkylacetamides have been measured and converted into excess molar volumes and heat capacities of the mixtures. In addition, the apparent and partial molar volumes and heat capacities of the various components have been evaluated. They vary smoothly with the mole fraction. The apparent molar heat capacities in the mixtures depend linearly on volume fraction, so that the partial molar heat capacities can be described using only one parameter for each mixture.     

Study of some volumetric and refractive properties of {PEG 300 (1) + ethanol (2)} mixtures at several temperatures

Molar volumes and excess molar volumes were investigated from measured density values for {PEG 300 (1) + ethanol (2)} binary mixtures at temperatures from 278.15 to 313.15 K. Both systems exhibit negative excess volumes probably due to increased interactions like hydrogen bonding and/or large differences in molar volumes of the components. Volume thermal expansion coefficients were also calculated for both binary mixtures and pure solvents. Refractive indices were also determined for all these non-aqueous mixtures and neat solvents at all temperatures. Furthermore, the Jouyban–Acree model was used for density, molar volume and refractive index correlations of the studied mixtures at different temperatures. The mean relative deviations between experimental and back-calculated density, molar volume and refractive index data were 0.07%, 0.99% and 0.01%, respectively.     

Excess molar volumes and deviation in viscosities of binary liquid mixtures of acrylic esters with hexane-1-ol at 303.15 and 313.15 K

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.     

Thermophysical and sonochemical behaviour of binary mixtures of decan-1-ol with halohydrocarbons at (T = 293.15 and 313.15) K

Densities and ultrasonic velocities of binary mixtures of decan-1-ol with 1,2-dichloroethane, 1,2-dibromoethane, and 1,1,2,2-tetrachloroethene have been measured over the entire range of composition at T = (293.15 and 313.15) K and at atmospheric pressure. From these results, the excess molar volumes, molar free volumes, excess molar isentropic compressibilities, limiting excess partial molar volumes, and isentropic compressibilities, intermolecular free lengths, and available volumes by three methods, thermal expansion coefficients, parameters related to space-filling ability, intermolecular free lengths, and molecular radii have been calculated. The experimental ultrasonic velocities have been analyzed in terms of the ideal mixture relations of Nomoto and Van Dael, Jacobson’s free length, Schaaff’s collision factor, Flory’s statistical, and Prigogine–Flory–Patterson theories and thermoacoustical parameters.