abstract
With the (re)advent of eutectic mixtures within the field of deep eutectic solvents, special attention has been given to the measurement of solid-liquid equilibrium (SLE) phase diagrams, supported by the relevant information they can provide on the molecular interactions and melting temperature depression of any given system. As such, this work investigates the SLE phase diagrams of mixtures between ionic liquids and tetraalkylammonium chlorides (methyl, ethyl, and propyl), with the goal of decreasing the melting temperature of ionic liquids and ammonium salts, thus, expanding their application scope. Results show that tetraalkylammonium salts exhibit negative deviations from thermodynamic ideality when mixed with ionic liquids, which are increased by increasing their alkyl chain length and are interpreted in terms of anion exchange mechanisms. In turn, this nonideality contributes greatly to depression of the melting point of the ionic liquids examined. Overall, this work demonstrates that the correct combination of tetraalkylammonium/ILs anions and cations can lead to significant melting point depressions in both species, thus creating new ionic liquid mixtures using an approach akin to that used to form deep eutectic solvents.
keywords
EUTECTIC SOLVENTS; CHOLINIUM; MIXTURES
subject category
Chemistry
authors
Martins, MAR; Abranches, DO; Silva, LP; Pinho, SP; Coutinho, JAP
our authors
Dinis O. Abranches
Assistant Researcher
Liliana Patrocínio da Silva
Collaborator
Simão Pedro de Almeida Pinho
CollaboratorGroups
G4 - Renewable Materials and Circular Economy
G6 - Virtual Materials and Artificial Intelligence
Projects
CICECO - Aveiro Institute of Materials (UIDB/50011/2020)
CICECO - Aveiro Institute of Materials (UIDP/50011/2020)
Associated Laboratory CICECO-Aveiro Institute of Materials (LA/P/0006/2020)
acknowledgements
This work was developed within the scope of the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020, UIDP/50011/2020 and LA/P/0006/2020, and CIMO (UIDB/00690/2020 and UIDP/00690/2020) and SusTEC (LA/P/0007/2021), financed by national funds through the FCT/MEC (PIDDAC). L.P.S. acknowledges FCT for her Ph.D. Grant (SFRH/BD/135976/2018).