Binary Mixtures Of Tetrahydrofuran Research Articles

Study of Thermodynamic Modeling of Isothermal and Isobaric Binary Mixtures in Vapor-Liquid Equilibrium (VLE) of Tetrahydrofuran with Benzene (303.15 K) Cyclohexane (333.15 K), Methanol (103 kPa), and Ethanol (100 kPa)

Tetrahydrofuran (THF) is an aprotic solvent with multiple applications in diverse areas of chemical, petrochemical, and pharmaceutical industries with an important impact in chemical waste liquid with other solvents. In this work, 51 available VLE data, for isothermal binary mixtures of THF(1) + Benzene(2) and THF(1) + Cyclohexane(2) at 303.15 and 333.15 K, respectively, and isobaric THF(1) + Methanol(2) at 103 kPa and THF(1) + Ethanol(2) at 100 kPa were used in the development of the activity coefficient models. The quality of experimental data was checked using the Herington test. VLE binary data was correlated with models Wilson, NRTL UNIQUAC, and UNIFAC to obtain binary parameters and activity coefficients. The best thermodynamic consistency when conducting the Herington test for the VLE data was found for the THF(1) +Cyclohexane(2) isothermal system and THF(1) + Ethanol(2) isobaric system. The UNIQUAC model for isothermal systems THF(1) + Benzene(2) and THF(1) + Cyclohexane(2), the NRTL model for the isobaric system THF(1) + Methanol(2), and the UNIQUAC model for THF(1) + Ethanol(2) perform better than the other models.

CNC dispersion in PLA and PBAT using two solvents: morphological and rheological properties

Cellulose nanocrystals (CNCs) were dispersed via solution casting in amorphous (A) and semi-crystalline (SC) poly (lactic acid) (PLA) and poly (butylene adipate-co-terephthalate) (PBAT). The protocol, optimized following the Hansen solubility parameter theory, relies on binary mixtures of tetrahydrofuran and dimethyl sulfoxide for the polymers and CNCs, respectively. First highlighted through atomic force microscopy, good filler dispersion and distribution were confirmed by a decrease of the linear viscoelastic region and significant increases of the complex viscosity, storage modulus, and apparent yield stress of the nanocomposites with CNC content, specifically at low frequencies. CNC percolation thresholds of 1, 0.3, and 0.3 wt% were determined in A-PLA, SC-PLA, and PBAT, respectively. These are the lowest to be reported in the literature until now. While PLA retained solvent traces, leading to a significant plasticizing effect, solvent removal was complete in PBAT. It was attributed to the crystallization of PBAT at the drying temperature (70 °C).

Molecular interaction studies in binary mixtures of tetrahydrofuran with arene-substituted alcohols: acoustic and volumetric study

ABSTRACTIn the present investigation, density and speed of sound have been reported for binary liquid mixtures of tetrahydrofuran with benzyl alcohol and 4-methoxybenzyl alcohol over the entire composition range at T = 303.15, 308.15 and 313.15 K. From the experimental data, excess molar volume (), excess isentropic compressibility (), excess molar isentropic compressibility (), and excess speed of sound () of liquid mixtures have been calculated. The excess partial molar volume,, , excess partial molar isentropic compressibility, , over the whole composition range together with partial molar volume,, , partial molar isentropic compressibility ,, excess partial molar volume,, , and excess partial molar isentropic compressibility, , at infinite dilution have also been calculated. All excess properties have been correlated using Redlich–Kister smoothing polynomial equation.

Organic solvent modifier and temperature effects in non-aqueous size-exclusion chromatography on reversed-phase columns

Common reversed-phase columns (C18, C4, phenyl, and cyano) offer inert surfaces suitable for the analysis of polymers by size-exclusion chromatography (SEC). The effect of tetrahydrofuran (THF) solvent and the mixtures of THF with a variety of common solvents used in high performance liquid chromatography (acetonitrile, methanol, dimethylformamide, 2-propanol, ethanol, acetone and chloroform) on reversed-phase stationary phase characteristics relevant to size exclusion were studied. The effect of solvent on the elution of polystyrene (PS) and poly(methyl methacrylate) (PMMA) and the effect of column temperature (within a relatively narrow range corresponding to typical chromatographic conditions, i.e., 10°C–60°C) on the SEC partition coefficients KSEC of PS and PMMA polymers, were also investigated. The bonded phases show remarkable differences in size separations when binary mixtures of THF with other solvents are used as the mobile phase. The solvent impact can be two-fold: (i) change of the polymeric coil size, and possible shape, and (ii) change of the stationary phase pore volume. If the effect of this impact is properly moderated, then the greatest benefit of optimized solute resolution can be achieved. Additionally, this work provides an insight on solvent-stationary phase interactions and their effects on column pore volume. The only effect of temperature observed in our studies was a decreased elution volume of the polymers with increasing temperature. SEC partition coefficients were temperature-independent in the range of 10°C–60°C and therefore, over this temperature range elution of PS and PMMA polymers is by near-ideal SEC on reversed-phase columns. Non-ideal SEC appears to occur for high molar mass PMMA polymers on a cyano column when alcohols are used as mobile phase modifiers.

Reply to “Comments on ‘Vapor–Liquid Equilibrium for Ternary and Binary Mixtures of Tetrahydrofuran, Cyclohexane, and 1,2-Propanediol at 101.3 kPa’”

Reply to “Comments on ‘Vapor–Liquid Equilibrium for Ternary and Binary Mixtures of Tetrahydrofuran, Cyclohexane, and 1,2-Propanediol at 101.3 kPa’”

Vapor–Liquid Equilibrium for Ternary and Binary Mixtures of Tetrahydrofuran, Cyclohexane, and 1,2-Propanediol at 101.3 kPa

Vapor–liquid equilibrium (VLE) data of the binary systems tetrahydrofuran + cyclohexane, tetrahydrofuran + 1,2-propanediol, and cyclohexane + 1,2-propanediol were reported at 101.3 kPa, as well as the ternary system tetrahydrofuran + cyclohexane + 1,2-propanediol. The results showed that the 1,2-propanediol was a good solvent which can break the binary azeotrope and effectively improve the relative volatility for the system of tetrahydrofuran and cyclohexane. Then, the equations of nonrandom two-liquid (NRTL), universal quasichemical (UNIQUAC), and Wilson were used to correlate the activity coefficients, and the results indicate that the NRTL model provides the best description of the phase equilibrium data.

Volumetric, viscometric and acoustic studies of ternary systems of tetrahydrofuran + 1,3-dioxolane with monoalkanoic acids and their corresponding binaries

The excess molar volumes (), viscosity deviations () and deviation in isentropic compressibilities () have been calculated from the measured density, viscosity and speeds of sound data over the whole composition range for the ternary systems of tetrahydrofuran (THF) + 1,3-dioxolane (1,3-DO) + formic acid, acetic acid, propionic acid and butyric acid and the constituent binary mixtures of tetrahydrofuran or 1,3-dioxolne + formic acid, acetic acid, propionic acid, butyric acid and tetrahydrofuran or 1,3-dioxolne at 298.15 K under atmospheric pressure. The excess or deviation properties of the binary and ternary systems were fitted to Redlich–Kister and Cibulka equations, respectively. The excess or deviation properties are found to be either negative or positive depending on the molecular interactions and the nature of liquid mixtures.

Densities and ultrasonic studies for binary mixtures of tetrahydrofuran with chlorobenzenes, chlorotoluenes and nitrotoluenes at 298.15 K

Densities ( ρ) and ultrasonic sound velocities ( u) have been measured over the whole composition range for the binary mixtures of tetrahydrofuran (THF) with 1,2-dichlorobenzene (1,2-DCB), 1,3-dichlorobenzene (1,3-DCB), 1,2,4-trichlorobenzene (1,2,4-TCB), o-chlorotoluene ( o-CT), m-chlorotoluene ( m-CT), p-chlorotoluene ( p-CT), o-nitrotoluene ( o-NT) and m-nitrotoluene ( m-NT) at 298.15 K and atmospheric pressure. To gain some insight into the several aggregations of molecular interactions present in these mixed solvents, we determined the excess molar volume ( V E) and the deviation in isentropic compressibilities (Δ κ s) as a function of the concentration of THF from the measured ρ and u, respectively. The V E values have been correlated using Redlich–Kister and Hwang et al. equations. The V E data is completely positive over the entire mole fraction range in all the binary mixtures of THF with chlorobenzenes, chlorotoluenes and nitrotoluenes. The sound velocity data have been obtained in terms of free length theory (FLT) and collision factor theory (CFT). The Δ κ s values have been correlated using Redlich–Kister equation. The values of Δ κ s were negative over the entire composition range in all the binary mixtures under the same experimental conditions. The measured data were discussed on the basis of intermolecular interactions and structural effects between unlike molecules. Based on our V E data of THF + DCBs or TCB and THF + chlorotoluenes are compared with existing V E data of THF + chlorobenzene (CB) and THF + toluene (TE), respectively.

Solubilities of (α,Z)-2-Amino-α-(methoxyimino)-4-thiazoleethanethioic Acid S-2-Benzothiazolyl Ester in Different Pure Solvents and Binary Mixtures of Tetrahydrofuran + Dichloromethane or 1,2-Dichloroethane

The solubility of (α,Z)-2-amino-α-(methoxyimino)-4-thiazoleethanethioic acid S-2-benzothiazolyl ester in dichloromethane, acetonitrile, tetrahydrofuran, 1,2-dichloroethane, acetone, and binary mixtures of tetrahydrofuran + dichloromethane or 1,2-dichloroethane was measured using a laser monitoring observation technique. The temperature dependence of the solubility of the solute was estimated using the modified Apelblat equation based on the data presented in this work. The calculated solubilities show good agreement with the experimental values.

Dielectric and spectrometric investigations of binary mixtures of tetrahydrofuran with propionic acid

The static permittivity (εm ) and the permittivity at the high-frequency limit (ε∞m ) of a binary mixture of propionic acid with tetrahydrofuran (THF) have been determined for different concentrations at temperatures of 303, 308, 313, and 318 K. The data have been used to compute the Kirkwood correlation factor, the excess permittivity, and the excess free-energy of the mixtures. The Kirkwood correlation factor is found to increase with increasing THF concentration. The mixture exhibited positive values of the excess permittivity and negative values of the excess free-energy of mixing, respectively. UV-Vis and FT-IR spectral measurements have also been carried out. The observed bathochromism and hypochromism in the UV-Vis spectra have been explained in terms of complex formation and ordering of dipoles of the complex. The FT-IR spectrum of the mixture shows considerable shifts in the positions of some of the absorption bands, indicating extensive hydrogen bonding between solute and solvent molecules.

Ultrasonic and viscometric studies of molecular interactions in binary mixtures of tetrahydrofuran with some aromatic hydrocarbons at temperatures from 288.15 to 318.15 K

Ultrasonic speed, u, and viscosity, η, of pure tetrahydrofuran (THF), benzene, toluene, o-xylene, m-xylene, p-xylene, mesitylene and those of their binary mixtures with THF as a common component, over the entire composition range expressed by mole fraction, x 1 of THF (0 ≤ x 1 ≤ 1), were measured at temperatures 288.15, 298.15, 308.15 and 318.15 K. From the experimental data, the deviations in isentropic compressibility, Δk s, in ultrasonic speed, Δu, and in viscosity, Δη were calculated. The partial molar compressibilities, and of THF and aromatic hydrocarbons in the mixtures over the whole composition range and and at infinite dilution and excess partial molar compressibilities, and , over the whole composition range and and at infinite dilution were calculated by using two different approaches. The variation of these parameters with composition and temperature of the mixtures are discussed in terms of molecular interaction in these mixtures. It is observed that the THF-aromatic hydrocarbon interaction in these mixtures follows the order: benzene > toluene > p-xylene > m-xylene > o-xylene > mesitylene. The effect of the number and position of the methyl groups in these aromatic hydrocarbons on the molecular interactions in these mixtures is also discussed.

Acoustic, viscometric and optical properties of binary mixtures of tetrahydrofuran with 1-propanol and 2-propanol

The values estimated from various mixing rules for the ultrasonic velocity, viscosity and refractive index have been compared with the respective values measured earlier at 293, 303, and 313 K over the entire mole fraction range of two binary mixtures of tetrahydrofuran (THF) with 1-propanol (1-p) and 2-propanol (2-p). There is an excellent agreement between the experimental values of ultrasonic velocity and of refractive index with the respective values obtained from the mixing rules. The mixing rules for viscosity provide values agreeing broadly with those obtained from experimental measurements. The relative merits and interrelations of these mixing rules are discussed.

Conductivity studies of sodium iodide in pure tetrahydrofuran and aqueous binary mixtures of tetrahydrofuran and 1,4-dioxane at 298.15 K

Electrical conductance measurements are reported for sodium iodide (NaI) in water + tetrahydrofuran (THF) and water + 1,4-dioxane binary mixtures at 298.15 K. The conductance data have been analyzed by the Fuoss conductance–concentration equation in terms of the limiting molar conductance (Λ 0), the association constant (K A) and the distance of closest approach of ions (R). Furthermore, the conductance data for pure THF have also been analyzed by the Fuoss–Kraus theory and the values of the ion-pair and triple-ion formation constants are calculated.

Densities, Viscosities, and Sound Speeds of Some Acetate Salts in Binary Mixtures of Tetrahydrofuran and Methanol at (303.15, 313.15, and 323.15) K

The densities and viscosities of ammonium acetate, potassium acetate, sodium acetate, and lithium acetate have been measured in 10, 20, and 30 mass % of tetrahydrofuran + methanol binary solvent mixtures at (303.15, 313.15, and 323.15) K. Apparent molar volumes (Vφ), partial molar expansibility (E2), viscosity B-coefficients, and free energy of activation for viscous flow (Δμ0*) are obtained from these data. The limiting apparent molar volumes (Vφ0) and experimental slopes ( ) derived from the Masson equation have been interpreted in terms of ion−solvent and ion−ion interactions, respectively. The viscosity data have been analyzed using the Jones−Dole equation, and the derived parameters B and A have also been interpreted in terms of ion−solvent and ion−ion interactions. The sound speeds measured at 303.15 K have been used to study the apparent molal isentropic compressibility (KS,φ), intermolecular free length (Lf), relative association (RA), relaxation strength (r‘), and specific acoustic impedance (Z) of the solutions.

Hydrogen bonding in binary mixtures of tetrahydrofuran and water: a concentration dependent Raman study and ab-initio calculations

Hydrogen bonding in binary mixtures of tetrahydrofuran and water: a concentration dependent Raman study and ab-initio calculations

Optical and volumetric study of molecular interactions in binary mixtures of tetrahydrofuran with 1-propanol and 2-propanol

The refractive indices and densities of binary mixtures of tetrahydrofuran (THF) with 1-propanol (1-P) and 2-propanol (2-P) over the entire composition range have been measured at 293, 303 and 313 K. Refractive index and density data have been used to evaluate the molar refraction deviation ΔR m and excess molar volume . The values of ΔR m and are negative for THF + 1-P mixture and are positive for THF + 2-P mixture. This suggests that specific interactions are taking place in THF + 1-P mixture while dispersive forces are responsible for behaviour of THF + 2-P mixture.

Investigation of solvatochromism and aggregation behavior of C60(C4H10N+)I− in binary solvent mixtures

Water-solubleN,N-dimethyl[60]fulleropyrrolidinium iodide (C60(C4H10N+)I−), when dissolved in binary mixtures of tetrahydrofuran and water, was found to exhibit remarkable solvatochromism. Correspondingly, the UV-vis spectra showed obvious changes by variation of the solvent composition of tetrahydrofuran and water. It was found that both concentration and temperature had strong influence on the stability of monomer-state C60(C4H10N+)I−, while they had little effect on the stability of aggregated C60(C4H10N+)I−. The formation of cluster was confirmed by TEM and AFM measurements.

Optical Absorption of Solvated Electrons in Water and Tetrahydrofuran/Water Mixtures

In the past Jou and Dorfman (J. Chem. Phys. 1973, 58, 4715) have determined the optical absorption spectra of solvated electrons (esolv-) in binary mixtures of tetrahydrofuran (THF) and water over the entire concentration range. From these experiments they concluded that the position of the absorption maximum and the width at half-height of the band are dominated by water. By additional experiments we show that at least for some mixtures with a mole fraction X(THF) ≤ 0.50, we obtain spectra at 298 K which agree almost completely with those of esolv- in pure water at elevated temperatures obtained by Jou and Freeman (J. Phys. Chem. 1979, 83, 2383). It follows that for this range of composition, excess electrons are obviously hydrated and the large amount of THF of up to X(THF) = 0.49 changes the water structure of the hydrated electron only slightly. The same effect can be produced by a temperature increase of T = 80 K in pure water. From the spectra we have determined equilibrium ground-state properties o...

Viscometric study of binary mixtures of tetrahydrofuran or tetrahydropyran + cyclohexane or toluene

Viscometric study of binary mixtures of tetrahydrofuran or tetrahydropyran + cyclohexane or toluene

Characterization of thermal diffusion of polystyrene in binary mixtures of THF/dioxane and THF/cyclohexane

The thermal diffusion coefficient (Dτ) was determined for three polystyrene standards of different molecular masses in binary mixtures of tetrahydrofuran/dioxane and tetrahydrofuran/cyclohexane of various compositions. The Dτ values were obtained by combining retention data from thermal field-flow fractionation measurements with diffusion data from dynamic light scattering experiments. In agreement with earlier work of Schimpf and Giddings, the thermal diffusion coefficient was found to be virtually independent of the molecular mass of the polymers. In the binary mixtures of tetrahydrofuran and dioxane, both good solvents for polystyrene, the Dτ value was approximately equal to the average of the Dτ values in the pure solvents, weighted according to the mole fractions of the solvents in the mixture. However, for polystyrene in binary mixtures of tetrahydrofuran and cyclohexane this linear behavior of the thermal diffusion phenomenon was not observed. The addition of cyclohexane to tetrahydrofuran has initially only a minor effect on the molecular and thermal diffusion coefficients of the polystyrene standards. Because cyclohexane is a theta solvent for polystyrene, the preferential solvation of polystyrene by tetrahydrofuran could be an explanation for these results. © 1996 John Wiley & Sons, Inc.