Advisor(s)
Abstract(s)
The solubility of syringic acid, vanillic acid and veratric acid was measured in pure water and eleven organic solvents
(methanol, ethanol, 1-propanol, 2-propanol, 2-butanone, ethyl acetate, acetonitrile, dimethylformamide,
1,2-propanediol, 1,3-propanediol and 1,3-butanediol), at 298.2 K and 313.2 K. Besides the solubility data, the
melting temperatures and enthalpies of the solutes were determined by differential scanning calorimetry,
while powder and single X-ray diffractionwere used to resolve the solute solid structure, before and after the solubility
studies.
Formodeling purposes, theNRTL-SACmodel, also combinedwith the Reference Solvent Approach (RSA), and the
Abraham solvation model were applied to describe the solid-liquid equilibria of the binary systems. A set of solvents
was used to estimate the model parameters and afterwards, solubility predictions were carried out for binary
systems not included in the correlation step. Better results were obtained using the Abraham solvation
model with average relative deviations (ARD) of 15% for the correlation set and 26% for the predictions, which
are more satisfactory than the results found with the NRTL-SAC model (33% for the correlation and 59% for the
predictions) or the NRTL-SAC model combined with RSA (30% for the correlation and 59% for the predictions).
Description
Keywords
Abraham solvation model Melting properties NRTL-SAC Phenolic acids X-ray diffraction
Citation
Vilas-Boas, Sérgio M.; Vieira, Vanessa; Brandão, Paula; Alves, Rebeca S.; Coutinho, João A.P.; Pinho, Simão P.; Ferreira, Olga (2019). Solvent and temperature effects on the solubility of syringic, vanillic or veratric acids: Experimental, modeling and solid phase studies. Journal of Molecular Liquids. ISSN 0167-7322. 289, p. 1-10