Isentropic Compressibilities Of Binary Mixtures Research Articles

Density, Viscosity, Refractive Index, Speed of Sound, Molar Volume, Isobaric Thermal Compressibility, Excess Gibbs Activation for Fluid Flow, and Isentropic Compressibility of Binary Mixtures of Methanol with Anisole and with Toluene at 298.15 K and 0.1 MPa

Density, viscosity, refractive index, and ultrasonic velocity were measured for the pure materials anisole, methanol, and toluene, and for the binary mixtures: methanol—anisole and methanol—toluene. Excess molar volume VE, isobaric thermal compressibility α, excess Gibbs activation energy for fluid flow ΔGE*, and excess isentropic compressibility κSE were calculated from the measured quantities. For both binary mixtures VE and κSE were <0 while Δn > 0 and ΔGE* > 0 over the entire mole fraction composition range. Anisole mixtures exhibited more negative values for VE and κSE while more positive values were displayed for Δn and ΔGE* compared to toluene mixtures. For Δη, negative values were observed at low alcohol concentrations but positive values at high alcohol concentrations for both systems.

Ultrasonic, Volumetric and Isentropic Compressibility of Binary Mixtures of 1,4-Dioxane with Primary Alcohols at 303.15 K

Density, viscosity and sound velocity of six binary liquid mixtures of methanol, ethanol, propanol, butanol, hexanol and octanol with 1,4-dioxane have been measured over the entire range of composition at temperature 303.15K. From the experimental densities, viscosities and sound velocity, the excess molar volume (VE), deviation in viscosity (Δη) and deviation in isentropic compressibility (ΔKS) have been calculated. The results have been used to discuss the nature and strength of intermolecular interactions in these mixtures.

Volumetric behaviour and isentropic compressibility of formamide with 2-dialkylaminoethanols

The volumetric properties and isentropic compressibilities of binary mixtures of formamide (FA) with 2-dialkylaminoethanols viz. 2-dimethylaminoethanol (2-DMAE) and 2-diethylaminoethanol (2-DEAE) were evaluated over the entire composition range at 303.15, 313.15 and 323.15 K and at atmospheric pressure. The excess partial molar volumes (V¯m,1E and V¯m,2E), excess isentropic compressibility (κsE), excess partial molar compressions (K¯s,m,1E and K¯s,m,2E) are deduced. The partial molar volumes (V¯m,1∘ and V¯m,2∘), partial molar compressions (K¯s,m,1∘ and K¯s,m,2∘), excess partial molar volumes (V¯m,1∘E and V¯m,2∘E), and excess partial molar compressions (K¯s,m,1∘E and K¯s,m,2∘E), at infinite dilution, over the entire composition range are also calculated. The knowledge of the volumetric properties and molar compression aids to understand specific molecular interactions existing between the FA and 2-DMAE/2-DEAE molecules of the binary system. The strength of intermolecular interactions in these mixtures follows the order: FA + 2-DEAE > FA + 2-DMAE. The required experimental data are used from our earlier work on the volumetric and acoustic study published in J. Mol. Liqs. 219 186 (2016).

Comment on the paper of Naushad Anwar Riyazuddeen and Shama Yasmeen entitled “Volumetric, compressibility and viscosity studies of binary mixtures of [EMIM][NTf2] with ethylacetate/methanol at (298.15–323.15) K”: A critical discussion on the application PFP model and isentropic compressibility analysis

Abstract The excess isentropic compressibilities of binary mixtures of 1-ethyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide with ethyl acetate or methanol and 1-butyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide with dimethyl sulfoxide or methanol were calculated based on thermodynamically rigorous ideal mixing rule. For the discussed mixtures, great differences between excess values of isentropic compressibilities and isentropic compressibility deviations from a simple mole fraction average of pure components isentropic compressibilities are observed. The usability and correctness of the Prigogine-Flory-Patterson (PFP) model for mixtures under test is discussed as well, because in constructing the PFP theory, hydrogen bonds and interactions of strong electrostatic nature are excluded [Fluid Phase Equilib. 233 (2005) 157].

Excess Molar Volumes, Excess Molar Enthalpies, and Excess Isentropic Compressibilities of Binary Mixtures Containing N-Methyl-2-Pyrrolidone and Isomeric Xylenes at 308.15 K

Excess molar volumes, excess molar enthalpies and speeds of sound of 1-methyl pyrrolidin-2-one + o- or m- or p-xylene binary mixtures have been measured over the entire composition range at 308.15 K. The speed of sound data were used to determine the excess isentropic compressibilities. It is observed that while the values of the excess molar enthalpies for the investigated mixtures are positive, the values of the excess molar volumes and excess isentropic compressibilities are negative over the entire composition range. The measured thermodynamic data have been analyzed in terms of Graph, Prigogine–Flory–Patterson, and the Sanchez and Lacombe theories. It is observed that Graph theory correctly predicts the signs and magnitudes of the excess molar volumes, excess molar enthalpies, and excess isentropic compressibilities of the studied mixtures. However, the excess molar volumes, excess molar enthalpies and excess isentropic compressibilities predicted by Prigogine–Flory–Patterson and Sanchez and Lacombe theories are of same sign.

Speeds of sound and isentropic compressibilities for binary mixtures of 1,2-ethanediol with 1-butanol, 1-hexanol, or 1-octanol in the temperature range from 293.15 to 313.15 K

Speeds of sound for binary mixtures of 1,2-ethanediol with 1-butanol, 1-hexanol, or 1-octanol were measured by means of pulse-echo-overlap method over the entire composition range and at temperatures ranging from 293.15 to 313.15K. From the measurement values and literature data on density, the excess molar isentropic compressibility was calculated and approximated by the Redlich–Kister polynomials. In two cases (mixtures with 1-butanol or 1-hexanol) the negative values of the excess molar compressibilities over the whole composition and temperature range are observed. In the third case (mixtures with 1-octanol) the s-shaped dependence is observed. The rigidity in mixtures under test increases from 1-octanol to 1-butanol. The excesses were discussed in terms of molecular interactions. The experimental data were used also for the calculation of the speeds of sound deviations. The ratios between excess and ideal values were calculated and discussed as well.

Densities, Speeds of Sound, and Isentropic Compressibilities of Binary Mixtures of {Alkan-1-ols + 1,2-Dimethylbenzene, or 1,3-Dimethylbenzene, or 1,4-Dimethylbenzene, or Ethylbenzene} at (293.15, 303.15, and 313.15) K

Densities and speeds of sound of binary liquid mixtures of {nonan-1-ol and decan-1-ol + 1,2-dimethylbenzene, or 1,3-dimethylbenzene, or 1,4-dimethylbenzene, or ethylbenzene} were measured over the entire composition range at (293.15, 303.15, and 313.15) K and at a pressure of 0.1 MPa. The experimental densities and speeds of sound were used to obtain the excess molar volumes and the isentropic compressibilities of the binary liquid mixtures. The Redlich−Kister polynomial was fitted to the excess molar volumes to derive the binary coefficients and the standard errors between the experimental and the calculated quantities. The excess molar volumes are positive for the binary liquid mixtures of {nonan-1-ol and decan-1-ol + ethylbenzene} over the entire composition range at (293.15 to 313.15) K. For the binary liquid mixtures of {nonan-1-ol + 1,2-dimethylbenzene, or 1,3-dimethylbenzene, or 1,4-dimethylbenzene}, the excess molar volumes show sigmoid trend, and the values vary from negative to positive over the whole composition range, except for the binary liquid mixtures of (nonan-1-ol + 1,2-dimethylbenzene) at (303.15 and 313.15) K where the excess molar volumes are positive over the whole composition range. For the binary liquid mixtures of {decan-1-ol + 1,2-dimethylbenzene, or 1,3-dimethylbenzene}, the excess molar volumes show slightly s-shaped trend at (293.15 and 303.15) K, but the excess molar volumes are positive over the whole composition range at T = 313.15 K for these binary liquid mixtures. For the binary liquid mixtures of {decan-1-ol + 1,4-dimethylbenzene), the excess molar volumes show sigmoid trend over the whole composition range at (293.15 to 313.15) K. As we go from nonan-1-ol to decan-1-ol and increase the temperature from (293.15 to 313.15) K, the excess molar volumes become more positive for all the binary liquids mixtures which indicate weak intermolecular interactions between (nonan-1-ol and decan-1-ol + aromatic hydrocarbon) at higher temperatures.

Densities, Speeds of Sound, and Isentropic Compressibilities for Binary Mixtures of 1,2-Ethanediol with 2-Ethyl-1-hexanol, 1-Heptanol, or Ethanol at the Temperature 298.15 K and Densities for Mixtures of 1,2-Ethanediol with 1-Nonanol at the Temperatures (293.15 and 298.15) K

Densities and speeds of sound for binary mixtures of 1,2-ethanediol with three alkanols (2-ethyl-1-hexanol, 1-heptanol, or ethanol) were measured over the entire composition range in the temperature 298.15 K by means of a vibrating-tube densimeter and pulse-echo-overlap method. Density measurements were also made for mixtures of 1,2-ethanediol with 1-nonanol at the temperatures (293.15 and 298.15) K. From these data, the excess molar volumes and excess molar isentropic compressibilities as well as the deviations of speed of sound were calculated and approximated by the Redlich−Kister polynomials. The negative values of the excess molar volumes and isentropic compressibilities over the entire composition range are observed only in the case of ethanol. In the cases of 2-ethyl-1-hexanol, 1-heptanol, and 1-nonanol, the positive values of the excess molar volumes over the entire composition range are observed. Simultaneously, the negative values of the excess molar isentropic compressibilities over the entire ...

Viscosities, speeds of sound and isentropic compressibilities for binary mixtures of 2-propoxyethanol with ethylene glycols

Viscosity, at T = 293.15 K, 298.15 and 303.15 K, and speed of sound, at 298.15 K, have been measured for the binary mixtures of 2-propoxyethanol (PE) with diethylene glycol (DEG), triethylene glycol (TEG) and tetraethylene glycol (TETRAEG), over the entire composition range. The speeds of sound values were combined with those of our previous results of densities to obtain isentropic compressibilities( κ s ) and their excess counterparts( κ s E ). The experimental data were used to calculate the values of deviation of viscosity (Δ η) and speed of sound ( δu), and excess energy of activation for viscous flow (Δ G 12 * E ). These parameters, especially excess functions, are found to be quite sensitive toward the intermolecular interactions in the studied liquid mixtures. The excess and deviations of studied functions have been correlated using Redlich–Kister type polynomial equation by the method of least-squares for the estimation of the binary coefficients and the standard errors. The viscosity data were correlated with equations of Hind et al., Grunberg and Nissan, Frenkel, and McAllister.

Densities, Speeds of Sound, and Isentropic Compressibilities for Binary Mixtures of 2-Ethyl-1-hexanol with 1-Pentanol, 1-Heptanol, or 1-Nonanol at the Temperature 298.15 K

Densities and speeds of sound for binary mixtures of 2-ethyl-1-hexanol with 1-pentanol, 1-heptanol, or 1-nonanol were measured over the entire composition range at the temperature 298.15 K by means of a vibrating tube densimeter and the pulse-echo-overlap method. Also, the densities for pure compounds in the temperature range from (288.15 to 318.15) K were measured. From experimental data, the excess molar volumes and excess molar isentropic compressibilities were calculated. The deviations of the speeds of sound were calculated as well. The Redlich−Kister polynomials were fitted to the results, and smooth representations of the results are presented. For the mixtures studied, the negative values of the excess molar isentropic compressibilities over the entire composition range are observed. The values of the excess molar volumes are negative over the entire composition range for mixtures of 2-ethyl-1-hexanol with 1-pentanol or 1-heptanol. For the mixtures of 2-ethyl-1-hexanol with 1-nonanol, the excess molar volume is slightly s-shaped; that is, the close zero or positive values in the 1-nonanol rich region are observed. The excesses are more negative as the carbon chain length of the 1-alkanol is shorter. The isobaric coefficients of thermal expansion for pure compounds were calculated by analytical differentiation of the density dependence on the temperature.

Isentropic and Excess Isentropic Compressibilities of Binary Mixtures Containing Cyclic Ethers and Chloroalkanes

Isentropic and excess isentropic compressibilities of binary mixtures formed by tetrahydrofuran or tetrahydropyran and isomeric chlorobutanes at 298.15 and 313.15 K have been calculated from experimental measurements of densities and speeds of sounds. Excess isentropic compressibilities are negative for all the mixtures except for the mixtures containing 1-chlorobutane at 298.15 K at very low concentrations of cyclic ether. Isentropic compressibilities and speeds of sound have been estimated using the Prigogine-Flory-Patterson theory and satisfactorily compared with the experimental values.

Speeds of Sound and Isentropic Compressibilities for Binary Mixtures of a Cyclic Diether with a Cyclic Compound at Three Temperatures

Speeds of sound of the binary mixtures of 1,3-dioxolane (or 1,4-dioxane) + cyclopentane (or cyclohexane, or benzene) have been measured at 283.15, 298.15, and 313.15 K. The excess isentropic compressibilities were calculated from experimental data and fitted with a Redlich-Kister polynomial function. Results were analyzed taking into account molecular interactions and structural effects in the mixtures and were compared with literature data. Isentropic compressibilities have been estimated at 298.15 K using the Prigogine-Flory-Patterson theory.

Excess Molar Volumes, Viscosity Deviations and Isentropic Compressibility of Binary Mixtures Containing 1,3-Dioxolane and Monoalcohols at 303.15 K

The excess molar volume (VE), 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.

Speeds of Sound and Isentropic Compressibilities of Binary Mixtures Containing Cyclic Ethers and Haloalkanes at 298.15 and 313.15 K

Speeds of sound of binary mixtures formed by either 1,3-dioxolane or 1,4-dioxane and isomeric chlorobutanes at 298.15 and 313.15 K are reported in this paper. Isentropic compressibilities and isentropic compressibility deviations have been calculated from experimental measurements. Isentropic compressibility deviations have been fitted to a Redlich–Kister equation, and the results have been discussed in terms of molecular interactions and structural effects. Isentropic compressibilities have been estimated at 298.15 K using the Prigogine–Flory–Patterson theory.

Speeds of sound and isentropic compressibilities of binary mixtures containing trialkylamines with alkanes and mono-alkylamines at 303.15 and 313.15 K

Isentropic compressibilities κ S, and excess isentropic compressibilities κ S E 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 κ S E have been interpreted in terms of molecular interactions and interstitial accommodation. The values of κ S E for TEA + alkane are positive while for TBA + alkane are negative. The values of κ S E 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 κ S E 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.

Speed of sound and isentropic compressibility of binary mixtures containing alkyl acetate or ethyl alkanoate, or ethyl bromo-alkanoate with hexane

Isentropic compressibilities κ S, excess isentropic compressibilities κ S E have been determined from measurements of speeds of sound u and densities π of eleven binary mixtures of alkyl acetate, or ethyl alkanoate, or ethyl bromoalkanoate with hexane at 303.15 K. Variable degree of polynomials were fitted to results. The values of κ S E regulary decrease with number of carbon atoms of the alkanoate going from positivevalues for methyl acetate + hexane to negative values for docecyl acetate + hexane. The values of κ S E for all four-ethyl bromoalkanoate mixtures are highly negative and their magnitude depends on the type of bromoester and the position of Br- atom in ethyl bromoalkanoates. The experimental speeds of sound have been analyzed in terms of collision factor theory (CFT), free length theory (FLT) and Prigogine-Flory-Patterson statistical theory (PFPT) of solutions.

Refractive Indices and Speeds of Sound of Binary Mixtures of N-Octane with 1-Alkanol at the Temperature 298.15 K

This paper reports experimental values for the refractive index, speed of sound, and isentropic compressibility of binary mixtures of n-octane with (1-butanol, 1-hexanol and 1-octanol) at the temperature of 298.15 K and atmospheric pressure, as a function of mole fraction. From the experimental values, the corresponding derived values were computed (changes of refractive index, changes of speed of sound and changes of isentropic compressibilities) using variable-degree polynomials to fit the data. Also, an attempt was made to correlate the behaviour of these magnitudes to the number of carbon atoms in the 1-alkanol chain.

Viscosities, speeds of sound and excess isentropic compressibilities of binary mixtures of alkyl alkanoate–hydrocarbons at 308.15 K and 318.15 K

The viscosities and speeds of sound of 15 binary mixtures of alkyl alkanoate (methyl- or ethyl propanoate and butanoate)–hydrocarbons ( n-heptane, benzene, chlorobenzene and 1,1,2,2-tetrachloroethane) have been measured at 308.15 K and 318.15 K. The mixture viscosities were correlated by Grunberg–Nissan, Hind and Auslander equations. The speeds of sound of all the mixtures were also predicted by free length theory (FLT) and collision factor theory (CFT) at 308.15 K. The excess isentropic compressibilities were calculated. The qualitative analysis of the excess isentropic compressibilities shows that disruption in dipolar associates of ester species by n-heptane in ester- n-heptane and the specific interactions of n– π and -O⋯⋯Cl-types in ester–benzene, -chlorobenzene and -1,1,2,2-tetrachloroethane mixtures are predominant.

Sound Velocities and Isentropic Compressibilities of Binary Mixtures of 1,1,1-Trichloroethane with Ketones and Esters at 303.15 K

Sound velocities for Binary mixtures of 1,1,1-Trichloroethane (TCE) with methyl ethyl ketone, methyl isobutyl ketone, acetophenone, cyclohexanone, methyl acetate, ethyl acetate, n-propyl acetate and n-butyl acetate were determined at 303.15 K. Isentropic compressibility (Ks ) were computed from sound velocity and density data, derived from excess volume. The deviation in isentropic compressibility (Ks ) exhibits negative values for mixtures of TCE with methyl ethyl ketone, methyl isobutyl ketone, acetophenone, cyclohexanone ethyl acetate, n-propyl acetate and n-butyl acetate. On the other hand, the quantity is positive over the entire range of composition for the mixtures of TCE with methyl acetate. The results are explained in terms of interactions between unlike molecules. Further, the experimental sound velocity data have been analysed in terms of free length theory (FLT) and collision factor theory (CFT).

Excess molar volumes and isentropic compressibilities of binary mixtures containing methyl methacrylate- n-alcohols at 303.15 and 313.15K

Excess molar volumes and isentropic compressibilities were measured at 303.15 and 313.15K over the whole range of composition for methyl methacrylate (MMA)- n-alcohol mixtures from density and sound velocities, respectively. Excess volumes for MMA-methanol and MMA-propanol were found to be negative for the entire range except at higher MMA concentrations. Positive excess volumes were, however, noted for MMA-butanol, MMA-pentanol and MMA-hexanol systems. The temperature coefficients of expansion at an ester mole fraction of 0.5 were estimated and observed to decrease with increase in the carbon chain-length of the alcohols. The excess isentropic compressibilities show a similar trend. The results are explained in terms of specific packing and non-specific dispersing interactions.