Solid–liquid equilibria in the acetic acid–propanoic acid and propanoic acid–trifluoroacetic acid systems

Abrman, Petr; Malijevská, Ivona

doi:10.1016/s0378-3812(99)00285-x

Cited by 20 publications

(6 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…From figure 5, excellent agreement between the experimental points obtained in this work with those obtained by Snow et al [13], Domanska and Kniaz [14] and Tanaka and Kawakami [15] for the (cyclohexane + hexadecane) system is observed. The The phase diagrams for all systems show a eutectic point, as observed in other studies on carboxylic acid systems by Abrman and Malijevská [20]. The experimental eutectic points for the (butyric acid + propionic or pentanoic acid) and (heptanoic acid + propionic, or butyric, or pentanoic, or hexanoic acid) systems are at T = 226.0 K (x 1 = 0.3797), T = 225.6 K (x 1 = 0.3733) and T = 231.5 K (x 1 = 0.3159), T = 241.3 K (x 1 = 0.4604), T = 227.8 K (x 1 = 0.3154), and T = 254.5 K (x 1 = 0.5005), respectively together with calculated eutectic points from the Wilson and NRTL models presented in table 9.…”

Section: Resultssupporting

confidence: 84%

Solid–liquid equilibria measurements for binary systems comprising (butyric acid+propionic or pentanoic acid) and (heptanoic acid+propionic or butyric or pentanoic or hexanoic acid)

Tadie¹,

Bahadur²,

Reddy³

et al. 2013

The Journal of Chemical Thermodynamics

View full text Add to dashboard Cite

Section: Resultssupporting

confidence: 84%

Solid–liquid equilibria measurements for binary systems comprising (butyric acid+propionic or pentanoic acid) and (heptanoic acid+propionic or butyric or pentanoic or hexanoic acid)

Tadie¹,

Bahadur²,

Reddy³

et al. 2013

The Journal of Chemical Thermodynamics

View full text Add to dashboard Cite

“…Binary phase equilibria provide information on the intermolecular forces between solvent and solute and s-l equilibria, eventually, on the formation and nature of intermolecular compounds in the solid phase. We found an addition compound in the solid phase in the systems propanoic acid-trifluoroacetic acid 1 , acetic acid-trichloroacetic acid 2 and acetic acid-formamide 3 . Although acetophenone is known to associate with acetic acid 4 , a simple sagged curve was obtained in the acetic acid-acetophenone system 3 with small positive deviations from Raoult′s law in the liquid phase.…”

mentioning

confidence: 88%

Solid-Liquid and Liquid-Liquid Equilibrium in the Formamide-Acetophenone System

Sedláková

Malijevská

Řehák

et al. 2006

Collect. Czech. Chem. Commun.

View full text Add to dashboard Cite

Solid-liquid (s-l) and liquid-liquid (l-l) equilibrium was determined in the binary system formamide-acetophenone. The s-l equilibrium was measured by recording time-temperature cooling and warming curves. The l-l equilibrium was obtained in a wide range of temperatures by the turbidity method. A considerable supercooling preceding solidification made it possible to examine metastable l-l equilibrium yet at temperatures lower than the solidus ones. Activity coefficients evaluated from the stable region of l-l equilibrium were correlated by Novák's modification of the Wilson equation. Calculation of the s-l equilibrium was performed with the obtained parameters. Heat capacity of solid and liquid acetophenone was measured and its dependence on temperature is given. The transition enthalpy betwen two solid modifications of acetophenone is also given.Since the Bronze Age mankind knows that mixing of two or more substances can lead to surprising results. Phase diagrams which are measured and studied also in our laboratory provide fundamental information on the equilibrium relations among different compounds. Our interest was especially focused on systems of strongly associating compounds. Binary phase equilibria provide information on the intermolecular forces between solvent and solute and s-l equilibria, eventually, on the formation and nature of intermolecular compounds in the solid phase. We found an addition compound in the solid phase in the systems propanoic acid-trifluoroacetic acid 1 , acetic acid-trichloroacetic acid 2 and acetic acid-formamide 3 . Although acetophenone is known to associate with acetic acid 4 , a simple sagged curve was obtained in the acetic acid-acetophenone system 3 with small positive deviations from Raoult′s law in the liquid phase.

show abstract

“…Although to date no mid-IR spectrum has been reported for a carboxylic acid bimolecule, these complexes have previously been studied by far-IR spectroscopy, 33,34 vapor density methods, 35 and by thermodynamic analysis of liquid 36 and solid mixtures. 37 The structure of the acetic acid-trifluoroacetic acid (Tfa) bimolecule, which crystallizes from the mixed acids at low temperatures, has been determined. 38 Theoretical studies of carboxylic acid bimolecules have been limited to semiempirical calculations of complexation energy and overall geometry of the FA-Tfa 21 and acetic acid-Tfa 39 bimolecules.…”

Section: Introductionmentioning

confidence: 99%

The Formic Acid−Trifluoroacetic Acid Bimolecule. Gas-Phase Infrared Spectrum and Computational Studies

Keller

2004

J. Phys. Chem. A

View full text Add to dashboard Cite

The gas-phase FT-IR spectrum of the formic acid−trifluoroacetic acid (FA−Tfa) hydrogen-bonded complex, or bimolecule, was obtained by numerical analysis of the FT-IR spectrum of a mixture of FA and Tfa vapors. Nineteen out of 24 vibrational modes predicted by ab initio frequency calculations to occur in the mid-IR range (400−4000 cm-1) were observed as well-defined absorbance peaks, with the other five occurring as complex or overlapped regions. Several hydrogen-bond-influenced vibrations of each monomer were identified, including CO stretching and COH in-plane and OH out-of-plane bending. These occurred at 1701, 1403, and 871 cm-1, respectively, for FA, and at 1774, 1325, and 942 cm-1, respectively, for Tfa. The hydrogen bond donated by Tfa in the bimolecule appears to be stronger than that in the Tfa dimer, while the FA-donated hydrogen bond is weaker than that in the FA dimer. Geometry optimization and vibrational frequency calculations were carried out at 21 levels of theory up to B3LYP/aug-cc-PVDZ. All levels of theory predicted an unsymmetrical complex, with hydrogen bond distances of 1.608 Å and 1.706 Å donated by Tfa and FA, respectively, and the corresponding O···O distances of 2.620 Å and 2.704 Å (B3LYP/aug-cc-PVDZ). These values differ from the symmetrical, or nearly symmetrical, structure derived from microwave spectra (Costain and Srivastava, J. Chem. Phys. 1964, 41, 1620−1627; Martinache et al. Chem. Phys. 1990, 148, 129−140). In agreement with previous experimental findings, the bimolecule was predicted to be more stable than either homodimer, with a calculated ΔH complexation of −14.2 kcal/mol (B3LYP/aug-cc-PVDZ). Mulliken population analysis predicted a polar complex with a transfer of 0.02−0.03 protons from Tfa to FA and a predicted dipole moment of 2.3−2.4 D, depending on the level of theory. The combined spectroscopic and computational evidence indicates that in this complex the Tfa-donated hydrogen bond is strengthened more than the FA-donated hydrogen bond is weakened.

show abstract

Solid–liquid equilibria in the acetic acid–propanoic acid and propanoic acid–trifluoroacetic acid systems

Cited by 20 publications

References 10 publications

Solid–liquid equilibria measurements for binary systems comprising (butyric acid+propionic or pentanoic acid) and (heptanoic acid+propionic or butyric or pentanoic or hexanoic acid)

Solid–liquid equilibria measurements for binary systems comprising (butyric acid+propionic or pentanoic acid) and (heptanoic acid+propionic or butyric or pentanoic or hexanoic acid)

Solid-Liquid and Liquid-Liquid Equilibrium in the Formamide-Acetophenone System

The Formic Acid−Trifluoroacetic Acid Bimolecule. Gas-Phase Infrared Spectrum and Computational Studies

Contact Info

Product

Resources

About