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Deep eutectic solvents have appeared as potential solvents for improving the extraction of polyphenols from vegetable or fruit matrixes. Since gallic acid is abundant in these sources, it is consid...

Research on the thermodynamics of electrolytes is timeless, and modeling an electrolyte solution might be considered to be a golden oldie, which was, is, and will be important in the design of proc...

Deep eutectic solvent (DES) formed by choline chloride and glutaric acid was tested for the separation of azeotropic mixtures of ethanol–ethyl acetate, n-propanol–n-propyl acetate, n-butanol–n-buty...

Vapor pressure measurements were applied to the systems guanidinium hydrochloride (methanamidine hydrochloride) + sodium l-glutamate (S-aminopenthanedioic acid sodium salt) + water at varying conce...

Furan compounds are of mounting global interest due to their biorenewable nature and their potential to replace petroleum-based compounds as feedstocks in manufacturing. In this work the solubilities of furfural and the furancarboxylic acids 2-furoic acid (FA), 5-formyl-2-furancarboxylic acid (FFA), and 2,5-furandicarboxylic acid (FDCA) in aqueous solutions and organic solvents were investigated experimentally and by modeling with perturbed-chain statistical associating fluid theory (PC-SAFT). The PC-SAFT pure-component parameters of the solutes FA, FFA, and FDCA and one binary parameter between each solute and each solvent were adjusted to fit experimentally determined solubilities of each solute in each organic solvent or in water. Pure-component parameters of furfural were fitted to experimental density data and vapor-pressure data, and a binary interaction parameter was fitted to capture the solubility behavior of furfural in water. Modeling of pH effects enhanced predictions of the mutual influences ...

This work provides experimental data and thermodynamic modeling on phase equilibria of binary mixtures that are relevant for esterification reactions. The components under investigation include water, succinic acid (SA), ethanol (EtOH), 1-butanol (1-BuOH), and the diesters of SA, namely, diethyl succinate (DES) and dibutyl succinate (DBS), respectively, as well as the organic solvents acetonitrile (ACN) and tetrahydrofuran (THF). Liquid–liquid equilibria (LLE) of water/DBS were measured at ambient pressure for temperatures between 313 and 353 K. Isobaric vapor–liquid equilibria (VLE) were measured for the binary systems ACN/DES, ACN/DBS, 1-BuOH/DBS, and THF/DBS at pressures of 10 or 20 or 30 kPa. Temperature ranges for the isobaric VLE varied between 300 and 500 K. The measured data and phase equilibria reported in literature were accurately modeled using perturbed-chain statistical associating fluid theory (PC-SAFT). For this purpose, pure-component PC-SAFT parameters, which were not already reported in ...

The solubility of the amino acids l-alanine and l-glutamic acid and its sodium salt (sodium l-glutamate monohydrate) in aqueous solutions at 30 °C and atmospheric pressure was investigated in the pH range between 3 and 9 and in the presence of the ionic liquids (ILs) 1-butyl-3-methylimidazolium trifluoromethanesulfonate ([bmim][OTf]) and choline dihydrogencitrate ([ch][dhcit]) at pH 7. The solubility of l-alanine and l-glutamic acid in the solutions without IL was measured by UV spectroscopy and with a gravimetrical method. In the presence of an IL HPLC-analysis was applied. The solid phases were characterized using Raman spectroscopy and powder X-ray diffraction to distinguish the amino acids from their salts. While the solubility of l-alanine did not depend on pH within the considered pH range, the solubility of l-glutamic acid strongly increased with increasing pH. Below pH 6.2 the solid phase was characterized to be l-glutamic acid, while sodium l-glutamate monohydrate was found to be the solid at pH ...

Vapor pressure osmometry was applied to the system aminomethanamidine hydrochloride (guanidinium hydrochloride, GndmCl) + (S)-aminobutanedioic acid hemimagnesium salt (magnesium l-aspartate, Mg-(l-Asp)2) + water for varying molalities of GndmCl and Mg-(l-Asp)2 (mMg-(Asp)2 = 0.1, 0.2, and 0.3 mol/kg and mGndmCl = 0.1–1.2 mol/kg) at T = 298.15 and 310.15 K. From vapor pressure osmometry, activities of water, activity coefficients of water, and the corresponding osmotic coefficients of the mixtures Mg-(l-Asp)2 + water and Mg-(l-Asp)2 + GndmCl + water have been calculated, both being directly related to the chemical potentials of the different species and therefore to their Gibbs energy. Electrolyte perturbed-chain statistical associating fluid theory (ePC-SAFT) accounting for Coulomb and short-range (hard chain, dispersion, association) interactions was used to model the own experimental data of binary Mg-(l-Asp)2 + water and ternary GndmCl + Mg-(l-Asp)2 + water solutions. ePC-SAFT was further applied to mod...