Excess Molar Isentropic Compressibility Research Articles

Exploring molecular interactions in active amyl alcohol-haloalkane systems through thermodynamic properties and Jouyban–Acree correlation

ABSTRACT A comprehensive study on the thermodynamic and transport properties of binary mixtures composed of active amyl alcohol (AAA) and haloalkane’s was conducted within a temperature range of 303.15 K to 313.15 K. Experimental data on densities (ρ), viscosities (η), and speeds of sound (u) were employed to calculate excess molar volume (V E ), isentropic compressibility (K s E ), viscosity deviation (Δη), and excess Gibbs free energy for viscous flow (∆G* E ). The impact of dipole moment on these excess properties was investigated to gain insights into the prevailing intermolecular interactions within the mixtures. The Prigogine – Flory – Patterson (PFP) theory is applied to identify the predominant molecular interaction. The accuracy of the Jouyban–Acree model in correlating densities (ρ), viscosities (η), and speeds of sound (u) with composition were evaluated, demonstrating satisfactory agreement with experimental data.

Insight into molecular interactions prevailing in N,N-dimethylformamide + alkyl acrylates mixtures at different temperatures: An experimental and theoretical investigation

The excess isentropic compressibility, excess speed of sound, excess molar isentropic compressibility and deviation in viscosity were evaluated from the experimental values of speeds of sound and viscosities of N,N-dimethylformamide + methyl acrylate/ethyl acrylate/n-butyl acrylate binary mixtures over the entire composition range at temperatures (288.15–318.15) K and pressure (101 kPa). Further, the partial molar isentropic compressibility; excess partial molar isentropic compressibility of the components over the entire composition range and also at infinite dilution have been calculated. These evaluated parameters have been interpreted in relations to prevailing interactions in these mixtures. These interactions were found dependent on the size of alkyl group in acrylate molecules and the amide-acrylate interactions decline with increase in size of the alkyl group. Moreover, the speeds of sound for the mixtures were calculated by scaled particle theory and the results compared well with the experimental results. Also, the viscosities of these mixtures were correlated by means of various empirical relations and the results were found in good agreement with the experimental results.

Thermodynamic excess properties of the methyl tert-butyl ether + benzene + cyclohexane ternary system and its binary subsystems at temperature T = (293.15, 298.15, 303.15, and 313.15) K and ambient pressure

ABSTRACT This work reports for the first time, the experimental densities and sound speeds for the ternary system {methyl tert-butyl ether + benzene + cyclohexane} within the temperature range (293.15 to 313.15) K and under ambient pressure conditions. The related binary subsystems have also been reported. Experimental data were used to derive excess molar volumes and excess isentropic compressibilities. Redlich-Kister and Cibulka’s equations correlated the binary and ternary excess properties, respectively, with standard deviations falling below the estimated uncertainties of the corresponding properties. The results have been interpreted in terms of molecular interactions between mixtures’ components and structural effects. Additionally, two symmetric (Kohler and Muggianu) and two asymmetric (Hillert and Toop) binary contribution models have been tested for their ability to predict the excess properties of the ternary excess properties.

Physical properties of tween 20 + di-potassium hydrogen phosphate anhydrous (or tri-potassium phosphate 1,5-hydrate) + water from 288.15 K to 318.15 K

ABSTRACT The present study investigates the characterisation of binary and ternary mixtures involving a surfactant such as Tween 20 and various potassium salts in aqueous solutions. The ternary mixtures can form two distinct immiscible liquid phases. Several physical properties, including refractive index, density, and speed of sound, were measured, and derived properties such as excess molar volume and isentropic compressibility were calculated. The research focuses on the behaviour of aqueous binary and ternary mixtures composed of Tween 20, salts (di-potassium hydrogen phosphate anhydrous and tri-potassium phosphate 1,5-hydrate), and water in their homogeneous phases. It examines the influence of the surfactant and salts and the effect of temperature on these physical properties for homogeneous mixtures. Additionally, the physical properties of the equilibrium phases were determined to cover all the homogeneous zones comprehensively.

Thermodynamic and transport properties of binary mixtures containing 1,2-propanediol with 2-methoxyethanol and 2-ethoxyethanol at different temperatures

In the present investigation density, speed of sound, and viscosity have been reported for binary liquid mixtures of 1,2-propanediol (1,2-PD) with 2-methoxyethanol (2-ME) and 2-ethoxyethanol (2-EE) over the entire composition range at T= (298.15–323.15) K. From the experimental data, excess molar volume, (VmE), excess isentropic compressibility, (κsE), excess molar isentropic compressibility, (κs,mE), excess speed of sound, (uE), excess isobaric thermal expansion,αpE, and deviation in viscosity (Δη) of liquid mixtures have been calculated. The excess partial molar volume,V¯m,1E, V¯m,2E , excess partial molar isentropic compressibility, K¯s,m,1EK¯s,m,2E over the whole composition range together with partial molar volume,V¯m,10, V¯m,20, partial molar isentropic compressibility K¯s,m,10,K¯s,m,20, excess partial molar volume,V¯m,10E, V¯m,20E and excess partial molar isentropic compressibility, K¯s,m,10E,K¯s,m,20E at infinite dilution have also been calculated. All excess properties have been correlated using the Redlich-Kister smoothing polynomial equation. The VmE results are analysed in the light of Prigogine-Flory-Patterson theory. Analysis of each of the three contributions viz. interactional, free volume, and P* to VmE has shown that interactional contribution and free volume effect are negative for all the mixtures, and P* contribution is positive for the mixtures of 2-ME. The variations of these parameters with changes in composition and temperature have been discussed in terms of intermolecular interactions prevailing in these mixtures. Further, the viscosities of these binary mixtures were correlated theoretically by using various empirical and semi-empirical models and the results were compared with the experimental findings.

Excess acoustic and volumetric properties of polyethylene glycol 200 + methyl/ethyl methacrylate binary mixtures at different temperatures: An experimental and theoretical study

The excess and partial molar properties of binary liquid mixtures can be used to unveil the prevailing intermolecular interactions. The densities, ρ and speeds of sound, u for pure polyethylene glycol 200 (PEG 200), methyl methacrylate, ethyl methacrylate and their binaries (PEG 200 + methyl/ethyl methacrylate) have been measured over the entire composition range in the temperature range (293.15 to 323.15) K at 5 K intervals and at pressure, p = 100 kPa. The excess molar volume, excess isentropic compressibility, excess speed of sound, excess intermolecular free length, excess molar isentropic compressibility and excess acoustic impedance were evaluated using the experimental data. The partial and excess partial molar volumes/compressibilities of the components at each mole fraction and at infinite dilution have also been calculated. The results have been interpreted on the basis of prevailing intermolecular interactions as well as structural effects between like and unlike molecules. The results indicate the effect of the size of alkyl group on excess functions and interactions in these systems and the PEG-methacrylate interactions follow the order: methyl methacrylate > ethyl methacrylate. Scaled particle theory has also been used for the theoretical estimation of the speeds of sound and compared with experimental values. FT-IR spectra of pure PEG 200, methyl methacrylate, ethyl methacrylate and equimolar PEG 200 + methyl methacrylate/ethyl methacrylate mixtures were also recorded and analysed for better understanding of prevailing intermolecular interaction.

Volumetric and ultrasonic studies of molecular interactions in binary mixtures of N,N-dimethylacetamide with some polyethylene glycols at temperatures from 293.15 to 323.15 K

The intermolecular interactions in N,N-dimethylacetamide (DMA) + polyethylene glycol (PEG) mixtures have been examined from the measurements of the densities, ρ and speeds of sound, u of DMA + PEG 200 or PEG 300 or PEG 400 or PEG 600 mixtures over the entire mole fraction range at temperatures, T = (293.15–323.15) K and atmospheric pressure. Various excess parameters, viz., excess molar volume, excess isentropic compressibility, excess intermolecular free length, excess speed of sound, excess molar isentropic compressibility and excess acoustic impedance were evaluated using measured data. These excess properties were correlated with the Redlich–Kister equation. In addition, the partial molar volume and compressibility; excess partial molar volume and compressibility of the components over the entire composition range; and partial molar volume and compressibility and excess partial molar volume and compressibility of the components at infinite dilution have also been calculated. These evaluated parameters have been interpreted by means of prevailing intermolecular interactions in these mixtures. The presence of strong intermolecular interactions among DMA and PEG molecules have been revealed from the evaluated parameters of these mixtures. The speeds of sound were predicted theoretically using scaled particle theory and compared with experimental values. FT-IR spectra of pure DMA, PEG 200 and their equimolar mixtures were also recorded and analysed for better understanding of prevailing intermolecular interaction.

Volumetric, acoustic and spectroscopic studies of molecular interactions in 1-butyl-3-methylimidazolium hexafluorophosphate + ethyl/propyl/n-butyl acetate binary mixtures at different temperatures

The purpose of this work is to investigate the influence of concentration, temperature and molecular size on intermolecular interactions in the mixtures of 1-butyl-3-methylimidazolium hexafluorophosphate [BMIM][PF6] with some alkyl acetates. The densities, ρ and speeds of sound, u for the 1-butyl-3-methylimidazolium hexafluorophosphate + ethyl acetate/propyl acetate/n-butyl acetate binary mixtures were measured over the entire range of composition at the temperatures, T = (293.15 – 323.15) K at 5 K intervals and at pressure, p = 101 kPa. The experimental data was used to calculate various excess properties, viz., excess molar volume, excess isentropic compressibility, excess intermolecular free length, excess speed of sound, excess molar isentropic compressibility and excess acoustic impedance. The partial molar volumes and compressibilities; and excess partial molar volumes and compressibilities of the components over the entire composition range and at infinite dilution have also been calculated. The results clearly indicated the presence of intermolecular interactions in these mixtures and the magnitude of [BMIM][PF6]-alkyl acetate interactions followed the order: ethyl acetate > propyl acetate > n-butyl acetate, i.e., the interactions were found dependent on the size of alkyl group of acetates. The speeds of sound were estimated theoretically using scaled particle theory and compared with experimental findings. FT-IR spectra of pure [BMIM][PF6], ethyl acetate, propyl acetate. n-butyl acetate and their equimolar mixtures were also recorded and analysed for better understanding of prevailing intermolecular interaction.

Molecular interaction study using density, viscosity, speed of sound and FT-IR in 2-methyl-2-butanol + alkoxyethanols: Experimental and modelling approach

In this article, the intermolecular interactions in the binary liquid mixtures of 2-methyl-2-butanol with alkoxyethanols viz., 2-ethoxyethanol, 2-propoxyethanol and 2-butoxyethanol have been interpreted using thermophysical properties. Density (ρ), viscosity (η) and speed of sound (u) of pure components and their binary mixtures have been measured over the entire range of composition at 298.15, 303.15 and 308.15 K and at pressure p = 0.10 MPa. The experimental data were used to calculate the thermophysical properties such as excess molar volume (VmE), excess molar isentropic compressibility (Ks,mE), excess speed of sound (uE), deviation in viscosity (Δη) and excess Gibbs free energy of activation for viscous flow (ΔG∗E). The changes in these properties with composition and temperature of the liquid mixtures were discussed in terms of intermolecular interactions. Also, the effect of increase in alkyl chain length of alkoxyethanol molecule on these properties has been studied. The excess functions and their deviations have been correlated using Redlich-Kister type polynomial equation. The experimentally measured values of viscosities have been correlated with various semi-empirical relations such as Grunberg-Nissan, Tamura-Kurata, Hind et al., Katti-Chaudhri, McAllister’s two parameter model, Heric-Brewer and McAllister’s three parameter model. Apart from this, Prigogine-Flory-Patterson (PFP) theory has been used for the estimation of VmE values for studied binary mixtures. FT-IR spectra of these liquid mixtures have also been studied.

A study on thermophysical properties of binary mixtures of n-hexane with benzene and some alkyl-substituted benzenes within temperature range (293.15–323.15) K: Experimental and modeling approach

The current work reports densities and sound speeds, and related thermodynamic excess properties, namely excess molar volumes and excess isentropic compressibilities, measured at temperatures from (293.15 to 323.15) K and under atmospheric pressure conditions for binary mixtures of n-hexane with benzene, toluene, ethylbenzene, o-xylene, m-xylene, and p-xylene. Redlich-Kister polynomial correlated the thermodynamic excess properties to test the quality of experimental data. Excess properties contributed to understanding molecular interactions between involved molecules and the peculiarities of their packing in the mixture. The Jouyban-Acree model was used to correlate the mixtures' experimental densities, sound speeds, and their related derived properties, namely isobaric thermal expansivities and isentropic compressibilities. The average absolute percentage deviation of the correlated values from the experimental ones was better than 0.036 %, 0.058 %, 0.040 %, and 0.146 % for density, sound speed, isobaric thermal expansivity, and isentropic compressibility, respectively, attesting to the robustness of the Jouyban-Acree correlations. Additionally, the Perturbed Chain Statistical Associating Fluid Theory Equation of State modeled the densities of the current mixtures. Schaaff's Collision Factor Theory and Nomoto's relation were compared for their ability to model the sound speeds of the mixtures. The efficacy of these models was tested by computing the average absolute percentage deviations between experimental and computed values. The modeled densities are reasonably concordant with experimental data, with an overall deviation of 0.02 %. Notably, Nomoto's relation exhibited superior performance over Schaaff's theory in modeling sound speeds of current mixtures, with an overall deviation of 0.33 %. The current findings underline the efficacy and versatility of the used models for thermodynamic modeling in systems of varying complexity.

Density, Speed of Sound and Derived Properties of Binary Mixtures Propiophenone + Butoxyethanol at T = (303.15, 308.15, 313.15 and 318.15) K

The current study reports the experimental density (ρ) and sound speed (u) values for binary mixes of liquids propiophenone + 2-butoxyethanol at atmospheric pressure (0.1 MPa) and T = (303.15, 308.15, 313.15 and 318.15) K for the full spectrum of composition. densities and sound speed measurements from experiments have been used to estimate excess isentropic compressibility (κsE), excess molar volume (VEm), excess molar isentropic compressibility (KEs,m), excess isobaric thermal expansivity (αEp) and excess sound speed (uE). The Redlich-Kister polynomials were used to correlate excess parameters. Excess partial molar volume quantities (VEm,1 and VEm,2) at infinite dilution and their limiting values (V0Em,1 and V0Em,2) have been analytically determined using Redlich-Kister polynomials from the experimental density data. The results have been analyzed in light of strength and interactions among molecular entities scope and extent prevalent in these mixtures.

Study of thermodynamic, transport and volumetric properties of nanofluids containing ZrO2 nanoparticles in polypropylene glycol, polyvinyl pyrrolidone and water.

Zirconium dioxide (ZrO2) nanofluids are used in cooling systems, solar energy, and heat exchangers, offering improved heat transfer and efficiency across a wide temperature range. The aim of this work was to study the influence of polypropylene glycol (PPG) and polyvinyl pyrrolidone (PVP) and aqueous solutions of them as a base fluid on stability, volumetric properties, and viscosity of nanofluids containing Zirconium oxide (ZrO2) nanoparticles. The stability of these nanofluids has been confirmed using UV-Vis spectroscopy, and the particle size distribution of the systems using dynamic light scattering (DLS). Among these systems ZrO2-PPG and ZrO2-H2O-PVP30% have appropriate stability. The density, speed of sound and viscosity of these nanofluids have been measured at T = (293.15 to 318.15) K. From these data, the excess molar volume (V E m) and isentropic compressibility (κ s) have been determined. The effects of ZrO2 nanoparticles and temperature have also been investigated on volumetric and transport properties of aqueous solutions of PPG and PVP. The (V E m) values were fitted to the Redlich-Kister, Ott et al., and polynomial equations. Also, the isentropic compressibility (κ s) values were correlated with the polynomial equation. The Eyring-NRTL and Eyring-mNRF models have been used for correlating of the viscosity of the nanofluids with temperature dependency. The performance of the Einstein, Brinkman, Lundgren and Batchelor models in the prediction of viscosity of the nanofluids has also been analyzed.

Density and speed of sound of (iodobenzene + n-alkane) liquid mixtures at T = (288.15 to 308.15) K. Application of the Prigogine-Flory-Patterson model

(Iodobenzene + n-alkane) liquid mixtures have been studied experimentally, in terms of densities (ρ) and speeds of sound (c), and theoretically, by the application of the Prigogine-Flory-Patterson (PFP) model. The n-alkanes considered are n-heptane, n-decane, n-dodecane, and n-tetradecane. ρ and c measurements have been performed at a pressure p = 0.1 MPa and in the temperature range T = (288.15 to 308.15) K. Excess molar volumes (VmE) and excess isentropic compressibilities (κSE) have been calculated and correlated by Redlich-Kister polynomials. (∂VmE/∂T)p curves at the same (p,T) conditions have been obtained from correlated VmE values. The mixtures are characterized by the following features: (i) VmE increases with the number of carbon atoms of the n-alkane (n), being negative for n = 7, small and S-shaped with positive and negative values for n = 10, and positive for n = 12 and n = 14; (ii) κSE and (∂VmE/∂T)p are negative, increase with n and are very close to zero for n = 14. From these experimental results and the knowledge of the excess molar enthalpies of mixtures containing fluorobenzene, chlorobenzene or bromobenzene with n-alkanes, we have inferred the presence of structural effects, especially important for n = 7 and less relevant for volumetric properties as n increases. The VmE obtained are compared with those of other (halogenated benzene + n-alkane) liquid mixtures existing in the literature, namely systems with fluorobenzene, chlorobenzene, and bromobenzene. From this comparison and the analysis of the isobaric thermal expansion coefficients of the pure compounds, it is inferred that the interactional effects on VmE do not vary appreciably with the length of the n-alkane, so the observed VmE variation is fundamentally determined by the corresponding variation of the contribution from structural effects. Moreover, the application of the PFP model supports this interpretation, providing free volume contributions to VmE that vary parallelly to VmE with the length of the n-alkane, and interactional contributions that rest approximately constant independently of the n-alkane size.

Volumetric and acoustic studies of binary mixtures of DEC with isomeric chlorobenzene at various temperatures

ABSTRACT Densities, ρ, and speeds of sound, u, of binary liquid mixtures of diethyl carbonate with 1,2-dichlorobenzene, 1,3-dichlorobenzene and 1,2,4-trichlorobenzene have been measured over the entire range of composition at 303.15 K, 308.15 K, 313.15 K and 318.15 K and at atmospheric pressure. From the experimental data of the density and speed of sound, the excess properties such as excess molar volume, V m E , excess isentropic compressibility, κ s E , excess molar isentropic compressibility, K s , m E , excess speed of sound, u E , and excess isobaric thermal expansion, α p E , have been calculated. For better knowledge of the solute and solvent interaction, excess partial molar volumes, V ˉ m , 1 E and V ˉ m , 2 E , and excess partial molar volumes, V ˉ m , 1 ∘ E and V ˉ m , 2 ∘ E of the components at infinite dilution have been measured. All the excess parameter values have been fitted using the Redlich–Kister polynomial smoothing equation. The calculated excess values have been analysed in terms of molecular interactions and structural effects.

Acoustic and volumetric study of binary mixtures containing Ethyl propionate with amides at various temperatures

The development of biofuels to replace fossil fuels has recently increased at an exponential rate. Many chemical molecules with a wide range of functional groups make up biofuels. There is a strong correlation between the interactions between these molecules and the performance of biofuels. In this paper, the authors presented the new findings related to interactions existing in ethyl propionate and Formamide(F), N-Methylformamide (NMF), and N, N-Dimethylformamide (DMF) in a pure state as well as in their mixtures. Densities and speeds of sound at various temperatures (298.15–323.15 K) and at ambient pressure 0.1 MPa have been measured for these mixtures. From experimental data, the excess properties such as excess molar volume, VmE, excess isentropic compressibility, κsE, excess molar isentropic compressibility, Ks,mE, excess speed of sound, uE, and excess isobaric thermal expansivity, αpE, of the investigated mixtures were calculated. All the excess parameter values were fitted using the Redlich-Kister polynomial smoothing equation. The results were analysed in terms of molecular interactions. The excess partial molar volume, V¯m,1E, V¯m,2E , excess partial molar isentropic compressibility, K¯s,m,1EK¯s,m,2E over the whole composition range together with partial molar volume, V¯m,10, V¯m,20, partial molar isentropic compressibility K¯s,m,10, K¯s,m,20, excess partial molar volume, V¯m,10E, V¯m,20E and excess partial molar isentropic compressibility, K¯s,m,10E,K¯s,m,20E at infinite dilution have also been calculated from the experimental density measurements and analytically obtained using Redlich-Kister polynomials. The variations of these parameters with changes in composition and temperature have been discussed in terms of intermolecular interactions prevailing in these mixtures.

Influence of alkyl chain length and temperature on the densities, viscosities and speeds of sound of binary liquid mixtures of {2-methyl-1-butanol + 2-ethoxyethanol, or 2-propoxyethanol, or 2-butoxyethanol} at T = (298.15, 303.15 and 308.15) K

Density (ρ), viscosity (η) and speed of sound (u) of pure components and binary mixtures of 2-methyl-1-butanol with alkoxyethanols viz., 2-ethoxyethanol, 2-propoxyethanol and 2-butoxyethanol have been measured over the entire range of composition at different temperatures T = (298.15, 303.15 and 308.15) K. Using the experimental data various thermophysical properties such as excess molar volume (VmE), excess molar isentropic compressibility (Ks,mE), excess speed of sound (uE), deviation in viscosity (Δη) and excess Gibb’s free energy of activation for viscous flow (ΔG∗E) have been calculated. The excess or deviation properties used to define the molecular interactions between like and unlike components. Further, the values of excess and deviation properties have been fitted to the Redlich-Kister polynomial equation. The measured viscosities have been correlated with various semi-empirical relations such as Grunberg-Nissan, Tamura-Kurata, Hind et al., Katti-Chaudhri, McAllister (three body interaction) model, Heric-Brewer and McAllister (four body interaction) model. Apart from this, Prigogine–Flory–Patterson (PFP) theory is also used for the estimation of VmE values for studied binary mixtures.

Study of molecular interactions in binary mixtures of 2-ethyl-1-hexanol with primary alcohols (propan-1-ol, 2- propen-1-ol and 2- propyn-1-ol) at various temperatures

ABSTRACT The densities (ρ), viscosities (η), and speeds of sound (u) were reported for binary mixtures of 2-ethyl-1-hexanol with aliphatic primary alcohols (propan-1-ol, 2-propen-1-ol, 2-propyn-1-ol) over the entire composition range from 303.15 K to 313.15 K and at atmospheric pressure 0.1 MPa. The excess parameters (VE,κs E), deviation in viscosity, excess partial molar volumes, ( and ) excess partial molar isentropic compressibility’s ( and ) of the components at infinite dilution were calculated from the densities, speeds of sound, and viscosities at experimental temperatures. The variation of these properties with composition of the mixtures suggests hydrogen bond and charge-transfer complex formation between 2-ethyl-1-hexanol and self-associated primary alcohols. The VE results have been analysed in the light of Prigogine-Flory-Patterson theory. An analysis of each of the three contributions, namely, interactional, free volume and P* to VE shows that interactional contribution was positive for all binary systems. The free volume effect and P* contribution were negative for all the mixtures. Furthermore, the FTIR spectra have been recorded at 298.15 K and found to be useful for understanding the presence of hydrogen bonding between dissimilar molecules in the liquid mixtures. A good agreement was obtained between excess quantities and spectroscopic data.

Experimental, theoretical, computational and spectroscopic analysis in binary liquid mixtures containing 1-propanol and C-1 to C-4 alkyl acetates (T = 298.15–318.15 K): Physicochemical properties and molecular interaction studies

The molecular interactions between 1-propanol (1P) (1) and alkyl acetates (AAc) (C1-C4) (2) were examined by understanding of thermophysical properties of given binary liquid mixtures. Density (ρ), viscosity (η) and speed of sound (u) were measured for 1P, AAc and their binary mixture at T = 298.15–318.15 K with interval of 5 K at 0.1 MPa. Experimental data of ρ, η and u were used to evaluate VmE (excess molar volume), uE (excess ultrasonic speed), Δη (deviation in viscosity), ksE (excess molar isentropic compressibility), G∗E (excess Gibbs free energy of activation of viscous flow), VfE (excess free volume), LfE (excess intermolecular free length) and VaE (excess available volume) and correlated with R.K. (Redlich-Kister polynomial) equation. VmE data was also examined in term of Graph theoretical approach (GTA) and Prigogine-Flory-Patterson (PFP) theory. Δη were analyzed by Bloomfield and Dewan model (BFD) and also examined in terms of Graph theoretical approach (GTA). The u data was examined by different correlations like Van Dael, Nomoto, JFLT (Jacobson’s free length theory), Impedance dependence and CFT (Schaaff’s collision factor theory). FT-IR spectroscopic studies provide important information for understanding the intermolecular interactions between 1P (1) and AAc (2) components in the binary mixture which is also recognized by GTA. Further, DFT studies indicated the strength of molecular interactions and supported the graph theory in predicting probable associative molecular species in the liquid mixtures.

Study of molecular interactions of monoethanolamine with some higher alcohols at 298.15 K

Abstract Experimental measurements of the viscosity, density, and ultrasonic parameters of monoethanolamine (MEA) with 1-butanol, 1-pentanol, and 1-hexanol were carried out at 298.15 K. The excess molar volume (V E), viscosity change (Δη), and isentropic compressibility (ΔK s) are calculated using the viscosity, density, and ultrasonic velocity data. A polynomial equation of the Redlich-Kister type was used to fit these values. With increasing mole fraction, the viscosity, the density and the ultrasonic velocity increase. As the concentration of MEA rises, the excess molar volume falls. All V E values for MEA and 1-hexanol are positive, meaning that V E increases. At all concentrations, isentropic compressibility and viscosity change exhibit negative values.

Analysis of thermo-physical properties and qualitative investigation of molecular interactions in terms of Graph Theoretical Approach in binary liquid mixtures containing 1-propanol + Amines (1,3-diaminopropane or 1,2-diaminopropane or 1-amino-2-propanol) at T = 298.15–318.15 K

In the present report, the molecular interactions between 1P (1-propanol) and Amines (1,3-DAP (1,3-diaminopropane) or 1,2-DAP (1,2-diaminopropane) or 1A2P (1-amino-2-propanol)) are examined by insight of thermo-physical properties of binary liquid mixtures. Density (ρ) and speed of sound (u) were measured for 1P, Amines and their binary mixture at T = 298.15–318.15 K at 0.1 MPa. Experimental data of ρ and u were used to evaluate VmE (excess molar volume), ksE (excess molar isentropic compressibility), VfE (excess free volume), uE (excess ultrasonic speed), LfE (excess intermolecular free length) and VaE (excess available volume). Further, these calculated properties were correlated with Redlich-Kister polynomial (R.K.). VmE data is also examined in term of GTA (Graph theoretical approach) and PFP (Prigogine-Flory-Patterson) theory. FT-IR spectroscopic studies supported the results and clearly indicated that a strong intermolecular interactions exist between 1P and Amines components in the binary mixture which is also recognized by GTA. The u data were examined by different correlations like Nomoto, Impedance dependence, Van Dael, JFLT (Jacobson’s free length theory) and CFT (Schaaff’s collision factor theory).