Ionic liquids for the selective solvent extraction of lithium from aqueous solutions: a theoretical selection using COSMO-RS
Date
2022Author
Olea, Felipe
Durán, Guillermo
Díaz, Georgina
Villarroel, Eduardo
Araya López, Claudio
Cabezas, Rene
Merlet, Gastón
Romero, Julio
Quijada Maldonado, Esteban
Publisher
MineralsDescription
Artículo de publicación SCOPUS - WOSMetadata
Show full item recordAbstract
In this study, the theoretical design of ionic liquids (ILs) for predicting selective extraction
of lithium from brines has been conducted using COSMO-RS. A theoretical model for the solvent
extraction (SX) of the metal species present in brines was established considering extraction stoi-
chiometry, the distribution of the extractants between aqueous and IL phases, and IL dissociation
in the aqueous phase. Theoretical results were validated using experimental extraction percentages
from previous works. Results indicate that, in general, the theoretical results for lithium extraction
follow experimental trends, except from magnesium extraction. Finally, based on the model, an IL
was proposed that was based on the phosphonium cation as the extractant, along with the phase
modifier tributylphosphate (TBP) in an organic diluent in order to improve selectivity for lithium ex-
traction over sodium. These results provide an insight for the application of ILs in lithium processing,
avoiding the long purification times reported in the conventional process.