Values Of Excess Molar Volume Research Articles

Densities and thermal expansions of (water + tetrahydrofuran) mixtures within the temperature range from (274.15 to 333.15) K at atmospheric pressure

The mixture {water (1) + tetrahydrofuran (2)} densities have been measured over the whole composition range at temperatures between (274.15 and 333.15 K) and atmospheric pressure using the vibration type densimeter. Values of excess molar volume and molar isobaric thermal expansion of the mixture as well as apparent/partial molar volumes (down at infinite dilution) for water and tetrahydrofuran (THF) have been calculated. It is shown that the formation of the water + THF mixture occurs with decreasing its volume under all the temperatures. Concentration dependences of partial molar volumes of water and THF are characterized by the presence of extreme regions. Standard (limiting) partial molar volumes of water and THF increase as the temperature is rising. Increase in both temperature and THF content influence on the value of molar isobaric expansion of the mixture in the same way.

Theoretical and experimental study of valeric acid and 1-alkanol: COSMO-RS method and structure factors

Abstract This paper attempts to describe the types and nature of interactions present in binary mixtures containing valeric acid and 1-alkanols (1-pentanol up to 1-decanol) using theoretical and experimental methods. The density and viscosity of the mixtures above were measured at temperatures of 293.15 K to 323.15 K. Values of excess molar volumes (VmE) and viscosity deviations(Δη) were calculated. The findings indicate that strong interactions occur in binary solutions containing short-range 1-alkanol, and increasing the length of the alcohol chain causes a weakening of intermolecular interactions. To confirm the experimental results, the conductor-like screening model for real solutions (COSMO-RS) method was used to calculate the activity coefficients of the compounds in the liquid mixtures and the contact probability (CP) of alcohols with the valeric acid. Then, the D parameter, the concentration-concentration structure factor (SCC(0)), and the chemical short-range order parameter (α') were obtained and used to describe the existing interactions for binary mixtures. For binary systems, viscosity and density data are novel and have not previously been reported.

Thermophysical study of the binary mixtures of triethyl phosphate with N-methylformamide, N,N-dimethylformamide and N,N-dimethylacetamide – Experimental and theoretical approach

Abstract Densities at (293.15, 298.15, 303.15 and 308.15) K, and viscosities and ultrasonic velocities at 298.15 K of binary liquid mixtures of triethyl phosphate with N-methylformamide, N,N-dimethylformamide and N,N-dimethylacetamide have been measured over the entire range of composition at p = 0.1 MPa. From the experimental data, values of excess molar volume, excess isentropic compressibility, viscosity deviation and excess Gibbs energy of activation for viscous flow have been calculated. These results were fitted to the Redlich-Kister-type polynomial equation. The viscosity deviations and the excess Gibbs energy were found to be positive for the all systems investigated, while the excess volumes and the excess isentropic compressibilities were negative for TEP + DMA and for TEP + DMF systems, and positive for mixtures TEP + NMF. These results were interpreted based on the strength of the specific interaction, size and shape of molecules. Molecular dynamics simulations were used to provide a detailed explanation of the differences between the TEP + NMF and other systems, which were ultimately traced to strong hydrogen bonding between NMF and TEP.

Densities and Thermal Expansion Coefficients of Pure Methylcyclohexane, 1-Methylcyclohexene, 4-Methylcyclohexene, 1-Methyl-1,4-cyclohexadiene, and Toluene and Binary Mixtures of Methylcyclohexane and Toluene at 283.15 K to 358.15 K and 1 atm

Densities and thermal expansion coefficients of pure methylcyclohexane, 1-methylcyclohexene, 4-methylcyclohexene, 1-methyl-1,4-cyclohexadiene, and toluene were measured by means of a vibrating tube densimeter. A wide range of temperature from 283.15 to 358.15 K was selected for the measurements. The densities and thermal expansion coefficients of binary mixtures of methylcyclohexane and toluene were also measured. Under the conditions of experimentation, positive values of excess molar volumes are observed for the methylcyclohexane-toluene system. Comparing the measured densities of pure components with the densities calculated from the five widely used density equations, the Costald equation is proved to be the most reliable in representing the experimental density data.

Thermodynamic study of binary mixtures of toluene with ionic liquids, 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide, 1-hexyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide and 1-butylpyridinium bis(trifluoromethylsulfonyl)imide

Abstract Densities, refractive indices and viscosities at 293.15, 298.15, 303.15, 308.15 and 313.15 K of binary mixtures of toluene with 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide, 1-hexyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide and 1-butylpyridinium bis(trifluoromethylsulfonyl)imide have been measured over the miscible region at p = 0.1 MPa. From the experimental data, values of excess molar volume, excess thermal expansion, deviation in refractive index, deviation in viscosity and excess Gibbs energy of activation for viscous flow have been calculated. These properties have been fitted to the Redlich-Kister-type polynomial equation in order to analyse non-ideal behaviour of the studied mixtures. Moreover, partial and apparent molar volumes of toluene and ionic liquid in their binary systems have been calculated. Finally, the effects of temperature and cation of ionic liquid on the physicochemical properties were analysed and discussed in terms of intermolecular interactions occurring in the studied systems.

Thermodynamic study of ester diethyl tartrate and its binary systems with iso-alcohols

Densities of pure ester diethyl tartrate and alcohols isobutanol and isopentanol are measured on high pressures up to 60 MPa and temperatures from 293.15 K to 413.15 K, while thermophysical properties for two systems ester + alcohol are obtained on atmospheric pressure and temperatures 288.15–323.15 K. High pressure densities were correlated with Tammann-Tait equation. Experimental data on atmospheric pressure for mixtures were used to determine derived properties, excess molar volume, viscosity and refractive index deviations, which are then correlated with Redlich-Kister polynomial equation. To support the discussion regarding interactions, FT-IR analyses of pure components and mixtures with highest absolute values of excess molar volume were presented. Additionally, viscosity modelling was performed with predictive and correlative models and results were discussed from the point of potential usage of applied models to calculate viscosity of investigated systems.

Experimental and modeling study of diisopropyl ether and 2-alkanol; PC-SAFT model and free volume theory

In the present study, with the aim to discover the governing interactions in binary mixtures containing diisopropyl ether and short-range 2-alkanol (from 2-propanol to 2-hexanol), experimental values of density and viscosity at temperature range 293.15 K–323.15 K were reported. From these data, values of excess molar volume, partial molar volume, and viscosity deviation for mentioned systems were calculated. Findings show that strong interactions occur among unlike molecules while increasing in the carbon chain length of 2-alkanol, reinforces the interactions. Also, the perturbed-chain SAFT (PC-SAFT) equation of state was implemented to study the density and partial molar volume of binary mixtures. Combination of this model with Free Volume Theory was applied for prediction of binary viscosities. Maximum deviation in AAD for density correlation regarding PC-SAFT model was 1.21%, and for viscosity calculation was 2.19%.

Effect of temperature and position of OH group in isomeric butanediols in intermolecular interactions with 2-chloroaniline: A thermodynamic, DFT and molecular dynamics approach

The pronounced effect of the position of the hydroxyl groups in isomeric butanediols (1, 2-butanediol (12BDL), 1, 3-butanediol (13BDL) and 1, 4-butanediol (14BDL)) in the formation of hydrogen bonds with 2-chloroaniline (2CA) was investigated by using experimental and computational methods. The density (ρ) and speed of sound (u) in binary mixture was determined at T = (303.15–318.15) K and at atmospheric pressure p = 0.1 MPa. Values of excess molar volume (VmE), and excess isentropic compressibility (ksE) were determined by using experimental data. It was observed that these excess properties (VmEksE) departs negatively from the ideal mixture which indicates the formation of intermolecular hydrogen bonds. The volumetric properties like excess partial molar volume (V‾m,1EV‾m,2E), partial molar volume (V‾m,10,V‾m,20) and excess partial molar volume (V‾m,10EV‾m,20E) are derived at infinite dilutions. Quantum mechanical approach was used to study the intermolecular hydrogen bond interactions in self and cross-associated complexes of 2-chloroaniline and isomeric butanediols with the aid of DFT in the gas phase, while classical molecular dynamic simulations were carried out in the liquid phase. Experimental, quantum mechanical and classical molecular dynamic methods are used to investigate the formation of a hydrogen-bonded network between 2-chloroaniline and isomeric butanediols mixtures. The investigated results were further confirmed by the existence of hydrogen bonding evolution between 2-chloroaniline and isomeric butanediols through FT-IR Spectral studies. The Fourier transform Infrared spectroscopic data strongly confirms and support the existence of intermolecular hydrogen bonding and molecular associations between component molecules.

Research On Ion-Solvent Interactions In The Inorganic Liquid Mixtures By Ultrasonic Technique

Ultrasonic speed, density and viscosity of binary liquid mixtures of aqueous ammonium per sulphate with other sulphate solutions at 303.15 K have been measured. From these experimental data, the adiabatic compressibility, intermolecular free length, internal pressure, acoustic impedance, relaxation time, molar volume, classical absorption coefficient and surface tension have been computed. The excess viscosity, excess compressibility, excess intermolecular free length, excess acoustic impedance and excess molar volume values are evaluated to find the nature and the extent of the interactions between the constituent molecules of the liquid mixture systems.

Thermodynamic, DFT and molecular dynamics studies of intermolecular interactions between 2-methoxyaniline and N- substituted amide mixtures

Abstract The experimental data of density(ρ) and speed of the sound(u) of 2-methoxyaniline and N-alkyl amides binary liquid mixtures have been evaluated at temperatures T = (303.15 to 318.15) K. Values of excess molar volume ( V m E ), excess isentropic compressibility ( k s E ), excess partial molar volumes ( V ¯ m , 1 E , V ¯ m , 2 E ) , and excess partial molar volumes at infinite dilution ( V ¯ m , 1 E , ∞ , V ¯ m , 2 E , ∞ ) over the whole composition range have been calculated by using the density and the speed of sound measurements. The calculated excess parameters were used to discuss the intermolecular interactions. A quantum mechanical approach was performed in gas phase and classical molecular dynamic simulations were done in liquid phase to study the intermolecular interactions in self and cross-associated complexes. The details of experimental, quantum mechanical and classical molecular dynamic methods are used to investigate the formation of a hydrogen-bonded network between 2-methoxyaniline and N-alkyl amide mixtures.

Effect of temperature and composition on the volumetric, acoustic and thermal properties of N,N-dimethylformamide + propan-1-ol mixture

The density (ρ), sound velocity (u) and specific heat capacity (cp) of a binary mixture of N,N-dimethylformamide and 1-propanol were measured over its entire composition range. The values of the obtained results were used to calculate the values of excess molar volume (VmE), molar expansion volume coefficient (Ep,m), molar isentropic (KS,m) and isothermal (KT,m) compressibility, isobaric (Cp,m) and isochoric (CV,m) molar heat capacity as well as their excess functions (Ep,mE,KS,mE,KT,mE,Cp,mE,CV,mE,uE). The analysis of changes in the physicochemical quantities was based on consideration us in an aspect of intermolecular interactions resulting changes in the mixture structure.

The molar surface quasi-Gibbs energy and its application to the binary mixtures of 1-(2-methoxyethyl)-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide [MOEMIM][NTf2] with methanol and ethanol

The IL (ionic liquid) 1-(2-methoxyethyl)-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide [MOEMIM][NTf2] was prepared and confirmed by 1H NMR (1H nuclear magnetic resonance) spectroscopy and 13C NMR (13C nuclear magnetic resonance) spectroscopy. The density and surface tension for the binary mixtures of [MOEMIM][NTf2] with methanol and ethanol were measured across the entire range of mole fraction (x1 = 0.0000–1.0000) at T = (288.15–318.15) K. The average molar volumes of the binary mixtures were calculated from the experimental density, which increased with the increase of mole fraction and temperature. The excess molar volumes, VmE, were obtained and fitted by Redlich–Kister equation. The interaction between ionic liquid and alcohol is the strongest efficient packing and/or attractive interaction at the minimum point. The lower the temperature was, the smaller the absolute value of excess molar volume was. The new function – the molar surface quasi-Gibbs energy of mixtures was obtained by us in this work. On a basis of molar surface quasi-Gibbs energy of mixtures, a new Eӧtvӧs equation was obtained of mixtures and applied to binary mixtures of [MOEMIM][NTf2] with alcohols. The absolute value of the slope of the new Eötvös equation is the mole surface entropy, s, and the intercept is the molar surface enthalpy, h, which is temperature-independent. The deviation of molar surface quasi-Gibbs energy, Δgs, of mixtures for [MOEMIM][NTf2] with methanol and ethanol were calculated. Δgs was well fitted by Redlich–Kister equation. In terms of Redlich–Kister’s parameters, Ai, a new method for estimating the surface tension, γ, with any component of the mixtures is proposed and the estimated values, γ (est.), are in good agreement with the corresponding experimental ones, γ(exp.).

Density, Speed of Sound, and Dynamic Viscosity of 1-Butyl-3-methylimidazolium Bis(trifluoromethylsulfonyl)imide/1-Butyl-3-methylimidazolium Hexafluorophosphate and N-Methylaniline Binary Systems from T = 298.15 to 323.15 K at 0.1 MPa

Density, speed of sound, and viscosity values were measured for different binary mixture concentrations of 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([Bmim][NTf2]) + N-methylaniline (NMA) and 1-butyl-3-methylimidazolium hexafluorophosphate ([Bmim][Pf6]) + NMA systems at temperatures from T = 298.15 to 323.15 K under atmospheric pressure. The excess values of molar volume, molar isentropic compressibility, intermolecular free length, and viscosity were calculated. The partial molar volumes and partial molar isentropic compressibilities at infinite dilutions were also estimated. The Redlich–Kister equation was utilized to evaluate coefficients and standard deviations. The mechanism of effective packing between [Bmim][NTf2]/[Bmim][Pf6] and NMA was represented by the negative excess molar volumes. In both the studied systems, the occurrence of strong chemical interactions was represented by the negative excess intermolecular free length values. The present work clearly showed that the simu...

The study of thermo-physical properties of binary liquid mixtures of isoamyl alcohol with amines at 298.15–308.15 K

ABSTRACTThe values of density (ρ), viscosity (η) and speed of sound (u) were measured for binary mixtures of 3-methyl-1-butanol (isoamyl alcohol) with n-butylamine (NBA), sec-butylamine (SBA), tert-butylamine (TBA), n-hexylamine (NHA) and n-octyl amine (NOA) over the entire range of mole fractions and at three temperatures (298.15, 303.15 and 308.15 K). From these measurements, the values of excess molar volume(VE), viscosity deviation (∆η), deviation in isentropic compressibility (∆ks), excess Gibbs free energy of activation of viscous flow (G*E) and Grungberg–Nissan interaction parameter (d′) have been calculated. The excess parameter deviations are fitted to Redlich–Kister-type polynomial equation using multi-parametric nonlinear regression analysis to estimate the binary coefficients and standard deviations. The results were discussed in terms of molecular interactions, dipole–dipole interactions and H-bond interactions between unlike molecules. Further, the effects of temperature and amine group in different amines were also studied for the binary mixtures.

Thermophysical Properties of Binary Mixtures of n-Dodecane with n-Alkylcyclohexanes: Experimental Measurements and Molecular Dynamics Simulations

Thermophysical properties (densities, speeds of sound, bulk moduli, and viscosities) of binary mixtures of n-dodecane with n-alkylcyclohexanes (propyl- to dodecylcyclohexane) were examined at various compositions and temperatures (293.15–333.15 K). Viscosities were analyzed using the McAllister three-body equation, and excess molar Gibbs energies of activation for viscous flow (ΔG*E) at 293.15 K were calculated. Because the ΔG*E values did not differ significantly from zero, the mixtures appear to behave ideally. In contrast, nonzero excess molar volume values obtained both experimentally and using molecular dynamics (MD) simulations suggest nonideal behavior. Excess molar volumes were the most negative for n-dodecylcyclohexane mixtures and increased with decreasing alkyl side-chain length eventually becoming slightly positive for mixtures containing n-propylcyclohexane. MD simulations were able to predict density, isentropic bulk modulus, and dynamic viscosity values, but the accuracy of the calculated d...

Measurement and Correlation of Density, Viscosity and Vapor Pressure for Binary Mixtures of a Hydrocarbon Fuel + Dimethoxy Methane

Densities, viscosity and bubble-point vapor pressures for binary mixtures of dimethoxy methane and a hydrocarbon fuel (exo-tetrahydrodicyclopentadiene) were measured over the whole composition range. The excess molar volumes ( $$ V_{\text{m}}^{\text{E}} $$ ) and viscosity deviations (Δη) for the binary systems were calculated from the density and viscosity data. The Antoine equation was fitted with the experimental vapor pressures, and the corresponding parameters were calculated. Positive values of excess molar volumes, negative viscosity deviations and positive deviations from Raoult’s law for the vapor pressures are observed. The three physical properties and the corresponding calculation results provide valuable information on the application and study of mixed liquid hydrocarbon fuels.

Binary mixtures of 2-methoxyaniline with various functional groups (Thermodynamic and transport properties)

Abstract In the binary mixtures of 2‑methoxyaniline with various functional groups (2-methylcyclohexanone, methyl benzoate, anisole and trichloroethene) the densities, speeds of sound and viscosities including those of pure liquids, were measured over the entire composition range at different temperatures (303.15, 30.18 and 313.15) K and atmospheric pressure 0.1 MPa. Using this experimentally determined data, the excess values of molar volume, isentropic compressibility, partial molar volumes, partial molar isentropic compressibilities and deviation in viscosity of these components at infinite dilution were calculated. The results are discussed both in terms breaking hydrogen bonds in the amine and the formation of π-π complexes between the unlike molecules.

Physical-Chemical Properties of Binary Liquid Mixtures of Isoamyl Alcohol with Chloroethanes at 298–308 K

The density (ρ), viscosity (η), and speed of sound (u) were measured for binary mixtures of 3‑methyl-1-butanol(isoamylalcohol) with 1,2-dichloroethane (DCE), 1,1,2-trichloroethane (TCE), and 1,1,2,2-tetrachloroethane (TECE) over the entire range of mole fractions and at temperature 298.15, 303.15, and 308.15 K. From these measurements, the values of excess molar volume (VE), deviation in viscosity (∆η), deviation in isentropic compressibility (∆ks), excess Gibbs free energy of activation of viscous flow (G*E) and Grunberg−Nissan interaction parameter (d ') have been calculated. The excess parameter deviations have been fitted to Redlich−Kister type polynomial equation using multiparametric nonlinear regression analysis to estimate the binary coefficients and standard deviations. The results were discussed in terms of molecular interactions and dipole-dipole interactions. The effects of temperature and chlorine atoms number of investigated chloroethanes were also studied for the binary mixtures.

Volumetric and refractive properties of 1,3,5,7-tetravinyl-1,3,5,7-tetramethylcyclotetrasiloxane with methoxybenzene, chlorobenzene, tert-butylbenzene and nitrobenzene at T = (298.15–318.15) K

In this work, the densities and refractive indices of 1,3,5,7-tetravinyl-1,3,5,7-tetramethylcyclotetrasiloxane with methoxybenzene, chlorobenzene, tert-butylbenzene and nitrobenzene at different temperatures T = (298.15, 303.15, 308.15, 313.15 and 318.15) K and atmospheric pressure using a DMA4500/RXA170 combined system were measured. Excess molar volumes, isobaric thermal expansion, molar refractions, and the deviations in refractive indices have been estimated. These parameters have been used to understand the interactions in the mixtures qualitatively. The values of excess molar volume were fitted to Redlich–Kister equation to check the accuracy of experimental data.

Correlations and Predictions of THF + 2-Alkanol Binary Mixtures Behaviour by PC-SAFT Model and Friction Theory

In this article the behavior of tetrahydrofuran (THF) + 2-alkanol namely 2-propanol, 2-butanol, 2-pentanol, 2-hexanol and 2-heptanol binary mixtures through the density and viscosity measurements have been studied as a function of composition and within the temperature range of 293.15–313.15 K. The excess molar volume, isobaric thermal expansivity, partial molar volumes, and viscosity deviations have been calculated. For all binary mixtures, values of excess molar volume are positive and viscosity deviations are negative while increasing with the alkyl chain of the alcohol. The results provide information on the interactions among the molecules in the pure state as well as the binary liquid mixtures. The measured densities and viscosities have been applied to test the applicability of the PC-SAFT model and friction theory coupled with the Peng–Robinson–Stryjek–Vera equation of state