From Phase Change Materials to Green Solvents: Hydrophobic Low Viscous Fatty Acid–Based Deep Eutectic Solvents

FLORINDO, CATARINA; BRANCO, LUÍS C.; ROMERO, LEILA; MARRUCHO, ISABEL M.; RINTOUL, IGNACIO

ACS Sustainable Chemistry & Engineering

ACS Publications

Lugar: Washington; Año: 2018 vol. 6 p. 3444 - 3895

2168-0485

p { margin-bottom: 0.25cm; line-height: 120%; }Inspired by the useof fatty acids in development of low temperature latent heat storagematerials, novel low viscous and hydrophobic deep eutectic solvents(DESs) based exclusively on fatty acids are herein proposed assustainable solvents. Three DESs were prepared by exclusivelycombining fatty acids, namely octanoic acid (C 8 ), nonanoic acid (C9 ), decanoic acid (C 10 ) and dodecanoic acid (C 12 ), which cansimultaneously act as hydrogen bond donors and acceptors. Theobtained fatty acid-based DESs were analyzed in order to check theirstructures, purities and proportions. Water stability was alsocarefully evaluated through 1 H NMR. Fatty-acid DESs melting point?sdiagrams were determined by visual observation. Good agreement wasobtained between the experimental eutectic point and that predictedby considering an ideal system of two individually meltingcompounds. Important solvent thermophysical properties, such asdensity and viscosity of the dried and water-saturated DESs weremeasured. Finally, the removal of bisphenol-A, a persistentmicropollutant present in aqueous environments illustrates thepotential of binary and ternary fatty acid-based DESs as extractionsolvents. All prepared DESs showed good ability to extractbisphenol-A from water with extraction efficiencies up to 92%.