Excess Thermal Expansion Coefficients Research Articles

Application of ERAS-model and PFP theory on excess and deviation properties for binary systems of ionic liquid + amine derivatives

Thermodynamics of mixtures includes ionic liquid 2-hydroxyethylammonium propionate [2-HEAPr] + 1-propanol, 3-amino-1-propanol [AP], 1-amino-2-propanol [MIPA], and monoethanolamine [MEA] were studied. Density ρ, speed of sound u, and refractive index nD of pure and mixtures were measured at T = (298.15, 308.15, 318.15) K. Excess molar volume VmE, excess partial molar volume Vm,iE, excess thermal expansion coefficient αE, isothermal coefficient of excess molar enthalpy (∂Hm∂P)T,x, deviations in isentropic compressibility Δ ks, and refractive index Δ nD were calculated and data correlated with Redlich-Kister polynomial relation. The Prigogine-Flory-Patterson (PFP) and Extended Real Associated Solution (ERAS) models were applied to analyze intramolecular and intermolecular interactions between like and unlike molecules. The accuracy of theoretical models were found to be in agreement with empirical results. Finally, the study confirmed the structures of the ILs using FT-IR and HNMR analysis.

New insights and updated correlations for density, viscosity, refractive index, and associated properties of aqueous 4-diethyl-amino-2-butanol solution

In this study, volumetric, viscometric, and refraction properties of binary 4-diethylamino-2-butanol (DEAB) and water mixture were comprehensively investigated over an entire range of amine concentration and a temperature range of 298.15-343.15 K. In addition to typical density, viscosity, refractive index, and their excess properties, the associated properties (including partial molar volume, apparent partial molar volume, partial molar volume and apparent partial molar volume at infinite dilution, thermal expansion coefficient, excess thermal expansion coefficient, Gibbs free energy, enthalpy, entropy, excess Gibbs free energy, and excess entropy for activation of viscous flow, molar polarizability, and molar free volume) were comprehensively considered. The obtained excess properties revealed that there was a strong contraction of liquid mixture through intermolecular interaction and/or preference molecular packing. Also, Gibbs free energy for activation of viscous flow was a key parameter affecting liquid viscosity. It was suggested that refractive index should be considered with density for a molar polarizability and a free molar volume for CO2 physical solubility. Additionally, the Redlich-Kister equation was very effective for correlating the studied excess physical properties.

Probing the ion-dipole interactions between the imidazolium-based ionic liquids and polyethylene glycol 200 using excess thermodynamic and spectroscopy studies

The use of volatile organic compounds in industrial applications has generally been considered as detrimental to the environment and been a contributor to unsustainable activity. Ionic liquids (ILs) are generally considered as “green” and ecologically friendly solvents compared to volatile organic solvents. In the application of ILs in various processes, they are typically mixed with other solvents in order to modify their physicochemical properties. Thus, the focus in the present study on the interactions between ILs and polymer via thermophysical properties together with FT-IR analysis. In this study, density (ρ), viscosity (η), speeds of sound (u), and refractive index (nD) of the binary mixtures of 1-butyl-3-methylimidazolium hexafluorophosphate (BMIM+PF6-), 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIM+BF4-) and 1-butyl-3-methylimidazolium tetrafluoroborate (BMIM+BF4-) with polyethylene glycol 200 (PEG200) were measured at (293.15, 303.15, 313.15, 323.15 and 333.15) K and at p = 0.1 MPa. Excess thermodynamic properties: excess molar volume (VE), excess isentropic compressibility (KsE), excess viscosity (ηE), excess refractive index (nDE) and excess thermal expansion coefficient (αPE) were calculated from the thermophysical properties for the new systems studied. Excess thermodynamic properties were best correlated using the Redlich-Kister polynomial equation. Excess thermodynamic properties such as excess molar volume (VE), excess isentropic compressibility (KsE), and excess thermal expansion coefficient (αPE), displayed negative deviations, while excess viscosity (ηE) and excess refractive index (nDE) exhibited positive deviations throughout the entire composition range for the new systems. In addition, FT-IR spectroscopy was further utilized to confirm the presence of ion–dipole interactions/hydrogen bonding between the molecules of ILs and PEG200. The results from FT-IR spectra support the results obtained from excess thermodynamic properties. The results from both excess thermodynamic properties and FT-IR spectroscopy analysis confirmed the presence of ion–dipole interactions/hydrogen bonding. The strength of the ion–dipole interactions formed between molecules of PEG200 and ions of ILs follows the order: EMIM+BF4- >BMIM+PF6- > BMIM+BF4-. This study of the ILs + PEG200 binary mixtures contributes to the knowledge of physicochemical properties of these mixtures which can be utilized in specific applications such polymeric electrolytes in different electrochemical devices.

Experimental, theoretical and computational study of binary systems of alkanolamines and alkylamines with cyclohexanol at different temperatures

Density, ρ, speed of sound, u, and the difference in the temperature before and after the mixing process , ΔT, were measured for binary mixtures containing of cyclohexanol (CYC) + diethanolamine (DEA) or triethanolamine (TEA) or butylamine (BUT) or hexylamine (HEX) at (303.15–318.15) K except ΔT at 303.15 K. The excess molar volume, VmE, excess partial molar volume, Vm,iE, excess thermal expansion coefficient, αE, isothermal coefficient of excess molar enthalpy,(∂HmE∂P)T,x, deviation in isentropic compressibility,Δκs, excess molar enthalpy,HmE, and excess partial molar enthalpy, Hm,iE, were also calculated. The calculated data were satisfactorily correlated by Redlich – Kister equation. Some empirical models such as (Prigogine–Flory–Paterson) PFP, Wilson, (Non-Random Two Liquid) NRTL and (universal quasi chemical) UNIQUAC. Computational methods were performed using density function theory (DFT) and molecular dynamics (MD) simulation and were used to discuss and compare intramolecular and intermolecular interactions. An acceptable agreement was found between empirical and theoretical data.

Density, refractive index, and derived properties of binary mixtures of water + ionic liquid 1-(2-hydroxyethyl)-3-methylimidazolium tetrafluoroborate

The density and refractive index were experimentally determined for binary mixtures of water + ionic liquid 1-(2-hydroxyethyl)-3-methylimidazolium tetrafluoroborate throughout the ionic liquid mass fraction range, at atmospheric pressure and various temperatures between 293.15 K and 323.15 K. The refractive index was measured at five wavelengths between 589.2 nm and 935 nm. From the experimental data on density, volumetric properties such as the excess molar volume and thermal expansion coefficient were calculated. The excess molar volume was negative throughout the ionic liquid mass fraction range and its magnitude decreased with temperature. From the experimental data on the refractive index, the deviation in the refractive index and its coefficients of concentration, temperature and chromatic dispersion were obtained. The values of the deviation in the refractive index were positive and decreased with temperature. In order to simultaneously investigate the dependence of the refractive index on concentration, temperature and wavelength, we correlated the experimental data with a two-term Cauchy equation. Furthermore, a comparative study of 11 refractive index mixing rules was performed to assess their prediction ability. More advanced mixing rules do not lead to any improvement in comparison with the simple linear mixing rule (Arago-Biot) for estimating refractive index and the concentration contrast factor of the mixture studied. The results are expected to be useful for tuning the properties of an ionic liquid by adding water or selecting the temperature or optical region.

Thermodynamic study of binary mixture of 2-butanol + monoethanolamine at different temperatures; PC-SAFT and ERAS models

In this paper, to study the possible intermolecular interactions in the binary mixtures 2-butanol with monoethanolamine, values of density were measured at temperatures 293.15 to 323.15 K and atmospheric pressure (P = 0.0815 MPa). From experimental densities, values of excess molar volume, VmE thermal expansion coefficient, α excess thermal expansion coefficient, αE and isothermal coefficient of excess molar enthalpy, (∂HmE/∂P)T, x were calculated. Excess molar volume is negative for the mentioned binary mixture over the whole range of concentration and becomes more negative with the increase in the temperature. ERAS model with the six adjustable parameters was used to correlate the excess molar volumes at different temperatures. Agreement between experimental data and predicted values through this model was reasonable at all temperatures. The maximum standard deviation for the mentioned binary mixture was 1%. Also, PC-SAFT model with one adjustable parameter and different schemes (2B, 3B, 4C) was applied to correlate the binary densities. A comparison among the performance of three approaches shows that the scheme 3B-2B at 293.15 K with the average absolute deviation (AAD) 1.63% has the best agreement with experimental data. When the PC-SAFT model with the prediction ability (p = 0) was implemented, the minimum of AAD increased to 4.66%.

Physicochemical parameters of the binary mixtures of formamide/N-methylformamide with 2-chloroethanol at different temperatures

ABSTRACT The pseudo-Gruneisen parameter , effective Debye temperature, acoustic nonlinearity parameter , internal pressure and isobaric thermal expansion coefficient have been evaluated for binary liquid mixtures of formamide (FA) and N-methylformamide (NMF) with 2-chloroethanol (2Cl-OH) at 298.15 K, 308.15 K and 318.15 K, over the entire concentration range. The excess pseudo-Gruneisen parameter , excess effective Debye temperature , excess nonlinearity parameter, excess internal pressure and excess isobaric thermal expansion coefficient were also calculated. The calculated values are reasonably satisfactory with the experimental results on sound propagation data of liquid mixtures. These physicochemical parameters play an important role in understanding of the significance of anharmonic and nonlinear behaviour with regard to intermolecular interactions in the liquid mixtures.

Volumetric properties of the liquid Cs-Pb system

ABSTRACT Density measurements are made on a series of caesium–lead liquid alloys containing 20 to 70 at.% Pb, in a temperature range from the liquidus line to ~1000 K. The experiments are carried out using the gamma-ray attenuation technique. Based on the obtained results, the concentration dependences of the molar volume, relative excess molar volume and volumetric coefficient of thermal expansion of the caesium–lead liquid system are described. These dependences strongly deviate from the corresponding dependences for ideal solutions, which confirms a tendency for compound formation in Cs–Pb melts.

Thermophysical Properties and Experimental and Modeling Density of Alkanol + Alkane Mixtures Using Neural Networks Developed with Differential Evolution Algorithm

Densities of pure 1-heptanol, 1-decanol, n-heptane, n-octane, n-nonane, n-decane, and their binary liquid mixtures were measured over the entire range of composition at (288.15, 293.15, 298.15, 303.15, 308.15, 313.15) K and at atmospheric pressure (0.1 MPa). The experimental data were used to determine several thermophysical properties including, the excess molar volume ($$ V_{m}^{E} $$) and coefficient of thermal expansion ($$ \alpha $$). These excess properties were used to analyze the inter–intra molecular interactions in the liquid mixtures. In addition, the densities of the considered mixtures were modelled using a combination of differential evolution algorithm and artificial neural networks. The proposed methodology determined good models that were able to efficiently predict the density with an average absolute relative error lower than 0.2 %.

Density, viscosity, surface tension and excess properties of 1, 3-propanediamine and tetraethylene glycol at T = 293.15 K–318.15 K

The density (ρ), viscosity (η) and surface tension (γ) of 1, 3-propanediamine (1, 3-PDA) and tetraethylene glycol (T4EG) binary mixtures at different temperatures (T = 293.15–318.15 K) were measured. Based on the density data, the excess molar volume (VmE), partial molar volume (V¯m,i), the excess Gibbs free energy (∆G⁎E) and thermal expansion coefficient (αp) of binary mixtures were calculated. Viscosity values (η) can be used to analyze the friction between fluids, and can be used in the design and application of chemical process equipment. Surface tension (γ) can be used to analyze intermolecular forces. The results were fitted to the Redli-Kister (RK) equation. The excess properties were analyzed from interaction at T4EG (1) + 1, 3-PDA (2) binary mixtures. According to the Gaussian calculation, the hydrogen bonding with 1.2 Å −3.0 Å bond length occurred in binary mixtures attributed to the positive dissociation energy of the binary mixtures. The results were further confirmed by FTIR and UV–vis and fluorescence spectra, the hydrogen bonds interaction mode was described as following:⋯HOC2H4OC2H4OC2H4OC2H4OH⋯N(H2)C3H6(H2)N⋯.

Thermophysical Properties Analysis of Poly (Ethylene Glycol) 600 + Methanol, Ethanol, 1-Propanol, and 2-Propanol Binary Liquid Mixtures

In this work, a series of thermophysical properties (apparent specific volume, excess molar volume, excess Gibbs energy of activation for viscous flow, coefficient of thermal expansion, excess coefficient of thermal expansion) of poly (ethylene glycol) 600 (PEG600) + methanol, ethanol, 1-propanol, and 2-propanol binary liquid mixtures were determined based on density and viscosity experimental measures at 293.15 K, 298.15 K, and 303.15 K and refractive indices at 298.15 K. After that, the obtained excess parameters were used to analyze the inter-intra molecular interactions in the liquid mixtures. In order to estimate the interaction parameters, the excess molar volume results were fitted to Redlich–Kister polynomial. Moreover, a set of semi-empirical relations were proposed to predict the viscosity of liquid mixtures.

Thermodynamic study of oxygenised fuel additives (isomeric butanediols with ethyl acetate) at 298.15-323.15K

ABSTRACT Densities, ρ, and Speeds of Sound, u, were measured for pure liquids of ethyl acetate, (EtOAc), 1,2-butanediol, (1,2-BD), 1,3-butanediol, (1,3-BD), 1,4-butanediol, (1,4-BD) and their binary mixtures {x 1 EtOAc + x 21,2-BD}, { x 1 EtOAc + x 21,3-BD}, and { x 1 EtOAc + x 21,4-BD} over the composition (EtOAc) and at temperatures (298.15–323.15) K at pressure 0.1 MPa. To understand the molecular interactions of solute–solvent, measured excess properties such as the excess molar volume, , excess isentropic compressibility, , excess speeds of sound, , excess molar isentropic compressibility, , thermal expansion coefficient, , excess thermal expansion coefficient, were calculated and fitted using the Redlich–Kister equation. For better understanding, also calculated partial molar volumes/isentropic compressibilities, and their excess properties at infinite dilution were measured. These parameters have been used to understand the interactions in the mixtures qualitatively. The experimental findings were compared through the usage of theoretical model developed by Prigogine–Flory–Patterson (PFP).

Thermophysical properties of 1-Hexyl-3-methylimidazolium nitrate and 2-alkanol; measurement and modeling

For binary systems containing 1-Hexyl-3-methylimidazolium nitrate ([Hmim][NO3]) ionic liquid and a homolog series of 2-alkanols, new data of density and viscosity at different temperatures and atmospheric pressure have been reported. Temperature range is 293.15–323.15 K, and the considered alcohols are 2-propanol, 2-butanol, and 2-pentanol. Regarding these data, values of thermal expansion coefficient, α excess thermal expansion coefficient, αE excess molar volume, VmE and deviation in viscosity, Δη were calculated. Both excess molar volumes and viscosity deviations are negative over the whole concentration range. The magnitude and type of interactions were interpreted versus the temperature and increase of carbon atom of alcohols. Findings show that strong interactions in the mixtures occur relative to the pure state, and intermolecular forces are weaker in the long-chain alcohols. For correlation and prediction of systems density, the Perturbed-Chain Statistical Associating Fluid Theory (PC-SAFT) was applied and results obtained from this theory are consistent with experimental data. Outcome densities from this theory were implemented for free volume theory to correlate the binary viscosities. Results are satisfactory with the maximum of 1.75% deviation from experimental viscosities. The whole data reported for binary systems are novel, and so far no reports have been investigated in scientific papers.

Transport, Thermodynamic, and Thermophysical Properties of Aqueous Mixtures of Poly (Ethylene Glycol): Experimental and Modeling

Density (ρ) and viscosity (η) of aqueous mixture containing poly(ethylene glycol)s (PEG)s with seven nominal molecular masses (1500 g·mol−1, 2000 g·mol−1, 3000 g·mol−1, 4000 g·mol−1, 6000 g·mol−1, 8000 g·mol−1, and 20 000 g·mol−1) have been experimentally measured at five temperatures (288.15 K, 293.15 K, 303.15 K, 308.15 K, and 313.15 K) and five concentrations of PEG (0.05, 0.10, 0.15, 0.20, and 0.25 mass fraction), at atmospheric pressure (0.1 MPa). Several thermophysical properties, including the apparent specific volume ( $$ V_{\varphi } $$ ), excess molar volume ( $$ V_{m}^{E} $$ ), coefficient of thermal expansion ( $$ \upalpha_{\text{P}} $$ ), excess coefficient of thermal expansion ( $$ \upalpha_{P}^{E} $$ ), were calculated using experimental data. The obtained excess parameters have been used to investigate the inter-intra molecular interactions in the liquid solutions. Moreover, the S-Wilson-NRF and modified UNIQUAC-FV thermodynamic models have been extended for the representation of the density of binary mixtures of PEG + water solutions and the original UNIFAC-VISCO, Z-UNIFAC-VISCO, UNIFAC-Sheng-VISCO, Chain-FV-VISCO, and UNIFAC-vdW-FV-VISCO thermodynamic models were applied to calculate the viscosity of PEG solutions. In addition, an alternative modeling approach in the form of artificial neural networks, developed with an evolutionary algorithm, namely differential evolution algorithm, was used for prediction of density of the mentioned solutions. The results of the neural network model show that this model is suitable for both correlation and prediction of the density of PEG solutions at different PEG molar masses, temperatures, and concentrations.

Investigation of Physico-chemical Properties for the 1-Butyl-3-methylimidazolium Tetrafluoroborate ([Bmim][BF4])–Diethylenetriamine (DETA) System for CO2 Capture

This paper presents the experimental values of densities, viscosities and refractive indices for 1-butyl-3-methylimidazolium tetrafluoroborate ([Bmim][BF4])–diethylenetriamine (DETA) mixtures over the entire composition range and temperature range 298.15–333.15 K. The physico-chemical properties such as excess molar volume, partial molar volume, partial molar volume at infinite dilution, apparent molar volume, apparent molar volume at infinite dilution, isobaric thermal expansion coefficient and excess isobaric thermal expansion coefficient were calculated from the experimental density data. The excess Gibbs energy and excess entropy of flow were determined from the viscosity data using Eyring’s theory of rate process. The specific interactions between molecules in mixtures were explained by analyzing the behavior of the thermodynamic excess/deviation properties. To determine the correlating accurately with the utilized models including the Redlich–Kister, modified Graber, Lorentz–Lorenz and McAllister equations, the adjustable parameters and standard deviations were determined. Moreover, the qualitative analysis of these properties was further legitimized with Fourier-transform infrared (FTIR) spectroscopic studies.

Thermophysical study of binary mixtures of 1-butyl-3-methylimidazolium nitrate ionic liquid + alcohols at different temperatures

New experimental data of density and viscosity for the binary mixtures of 1-butyl-3-methylimidazolium nitrate ([Bmim][NO3]) with + 2-propanol, 2-butanol and 2-pentanol are reported over the entire range of mole fraction at T = (293.15–323.15) K. To elucidate possible intermolecular interactions between the chemical species present in solutions, the excess molar volume, VmE thermal expansion coefficient, α excess thermal expansion coefficient, αE the isothermal coefficient of excess molar enthalpy, ∂HmE/∂PT,x partial molar volume, Vi¯ and deviation in viscosity, Δη were calculated. The excess molar volume of the binary mixture is negative over the entire mole fraction range and becomes more negative with increase in the temperature. Deviation in the viscosity is negative over the whole range of composition and decreases with increasing temperature. The obtained excess molar volume and deviation in viscosity were fitted to the Redlich–Kister polynomial equation. The experimental results have been discussed regarding molecular interactions and the formation of complex between unlike molecules. Influences of temperature and carbon chain length of alcohols were discussed.

The density, dynamic viscosity and kinematic viscosity of protic and aprotic polar solvent (pure and mixed) systems: An experimental and theoretical insight of thermophysical properties

We report herein the thermophysical properties of pure protic and aprotic polar solvents (water, dimethyl sulfoxide and N,N-dimethyl formamide) and their mixed (binary and ternary) systems. The experimental density (ρ) and viscosity (η) were determined for these systems by varying temperature range from 293.15 K to 343.15 K. The excess properties (viz., excess molar volumes (VE), excess thermal expansion coefficient (αE), viscosity deviation (Δη) and excess Gibb's free energy (ΔGE) for viscous flow) were computed for mixed systems from experimental values. The excess properties of the mixed systems show clearly a non-ideal behaviour. Especially, a mixture of water with aprotic polar component show better thermophysical properties than pure systems. The pure (DMF) system shows increasing dynamic viscosity values at higher temperature region. Both the binary as well as ternary mixed systems show maximum activation energy (Ea) in the presence of water depicts their thermal stability of the mixed systems. The thermal expansion coefficient (α) also revealed increase in the thermal behaviour for the protic-aprotic systems. In addition to that, thermodynamic parameters are also evaluated for better understanding of thermal stability.

Viscosity and Density of Binary Mixtures of Ethanol + Igepal (CO-520, CO-630, CO-720, and CA-720)

Surfactants are widely used for academic and industrial purposes. For this reason, thermodynamic and physical properties of surfactant and cosurfactant mixtures can provide important information about the nature of the molecular interactions present. In this work, volumetric and transport data of surfactant binary mixtures of the ethanol + Igepal series (Igepal CO-520, Igepal CO-630, Igepal CO-720, and Igepal CA-720) were determined experimentally within a range of temperature of T = 293.15–323.15 K, at atmospheric pressure. From these data, the following derivative properties have been calculated: the excess molar volume, viscosity deviation, and coefficient of thermal expansion. All of these mixtures showed that attractive intermolecular forces are dominant.

Volumetric and Ultrasonic Study of Mixtures of Benzyl Alcohol with 1-Propanol, 2-Propanol, and 1,2-Propandiol, 1,3-Propandiol and T-butanol

Densities and speeds of sound for five binary mixtures of benzylalcohol with 1,3-propandiol, 1- propanol, 2- propanol, 1,2-propandiol and phenylethnol were measured over the entire range of composition and at five temperatures from 298.15K to 323.15K at 5K interval and atmospheric pressure using a vibrating u-tube densimeter (DSA 5000). Besides, the densities for pure compounds in the above-mentioned temperature range were measured. The experimental densities were used to calculate the excess molar volumes, isentropic compressibility changes, the excess thermal expansion coefficients, and the excess partial molar volumes at infinite dilution, The results have been used to discuss the nature and strength of intermolecular interactions in these mixtures. The calculated excess and deviations quantities are correlated with the third-order Redlich–Kister equation. As a final work we modeled the experiment results by using TM and PR EOSs. This is clear that the results with TM EOS are more acceptable than PR EOS. TM and PR EOS can successfully predict density and excess molar volume. And are unable to predict speed of sound.

On the thermodynamic properties of solutions containing 2-hydroxy ethylammonium formate ionic liquid

Speeds of sound and densities for a set of binary mixtures including ionic liquid, 2-hydroxy ethyl ammonium formate (2-HEAF), with benzyl alcohol, 2-butanol and 1,2-butanediol, that are new in literature, were measured over the entire composition range and at six temperatures from 298.15 K to 323.15 K and atmospheric pressure by means of vibrating tube densitometer DSA 5000. From the experimental data, the excess molar properties consisting of excess molar volume, the excess thermal expansion coefficients, and the excess partial molar volumes, the excess partial molar volumes at infinite dilution, and deviation in isentropic compressibility, were calculated and correlated with the third-order Redlich–Kister equation. The results have been used to discuss the nature and strength of intermolecular interactions in these mixtures. Finally, it has been checked how the calculated values of densities using the Tao-Mason (TM) equation of state passes through the measured ones.