resumo
hydrophobic substances in water. Moreover, water, when present in small quantities, has also been shown to increase the solubility of hydrophobic substances in Cyrene. In spite of large practical importance, the understanding of the solvation ability of water/Cyrene mixtures is hampered by a lack of fundamental knowledge of their solvation mechanisms, which is further complicated by a chemical equilibrium established between the ketone form of Cyrene and water, yielding the diol form of Cyrene. In this work, the conductor-like screening model for real solvents (COSMO-RS) is used to rationalize the cosolvency effect of water on Cyrene. It is shown here that COSMO-RS can accurately predict the solubility of hydrophobic substances in water/Cyrene mixtures in the entire composition range from pure water to pure Cyrene. The predictions of the model show that the ketone form of Cyrene controls its hydrotropic ability, supporting the concept of cooperative hydrotropy. Using COSMO-RS to assess molecular contact probability, it is also shown that water, when added in small quantities to Cyrene, acts as a cosolvent by preferentially interacting with the solute as a hydrogen bond acceptor, effectively doubling the hydrogen-bond donning ability of the solute and, thus, maximizing the interactions with Cyrene. In turn, this leads to a solubility increase of hydrophobic substances in wet Cyrene.
palavras-chave
DIHYDROLEVOGLUCOSENONE CYRENE; SOLVENT
categoria
Engineering
autores
Abranches, DO; Benfica, J; Shimizu, S; Coutinho, JAP
nossos autores
Dinis O. Abranches
Investigador Auxiliar
Jordana Benfica
ColaboradorGrupos
G4 - Materiais Renováveis e Economia Circular
G6 - Materiais Virtuais e Inteligência Artificial
Projectos
agradecimentos
This work was developed within the scope of the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020 & UIDP/50011/2020 financed by national funds through the FCT/MEC, and when appropriate, cofinanced by FEDER under the PT2020 Partnership Agreement. Support was provided by the AllNat project -POCI-01-0145-FEDER-030463 (PTDC/EQU-EPQ/30463/2017), financed by ERDF funds through COMPETE2020 -Competitiveness and Internationalization Operational Program (POCI). FCT is also acknowledged for the financial support through the project SAICTPAC/0040/2015.