resumo
The possibility of developing a scale for solubility parameters, with the purpose of predicting the performance and aiding the selection of ILs, was evaluated. For the estimation of solubility parameters, infinite-dilution activity coefficient data were used. The results allowed the identification of a curious behavior for ILs that seem to present more than one solubility parameter, acting as polar molecules in some situations and as nonpolar molecules in others, depending on the medium. This behavior was confirmed by solubility measurements of [C4MIM] [PF6] in solvent mixtures. In this work, the solubility parameters were also estimated from other properties, namely, viscosities and enthalpies of vaporization, and the relation between the various sets of solubility parameters is discussed. The results obtained suggest that, given the complexity of IL molecules and their liquid phases, a one-dimensional scale for solubility parameters that is able to characterize these fluids is not feasible.
palavras-chave
DILUTION ACTIVITY-COEFFICIENTS; INVERSE GAS-CHROMATOGRAPHY; 1-BUTYL-3-METHYLIMIDAZOLIUM METHYL SULFATE; PRESSURE CARBON-DIOXIDE; EXCESS MOLAR PROPERTIES; REGULAR SOLUTION THEORY; INFINITE-DILUTION; THERMODYNAMIC PROPERTIES; BINARY-MIXTURES; ORGANIC SOLUTES
categoria
Chemistry
autores
Batista, MLS; Neves, CMSS; Carvalho, PJ; Gani, R; Coutinho, JAP
nossos autores
Catarina Maia Seco Seiça Neves
Investigador Auxiliar
Marta Luísa Salsas Batista
Estudante de doutoramento
Pedro J. Carvalho
Professor Auxiliaragradecimentos
The authors acknowledge financial support from Fundacao para a Ciencia e a Tecnologia through the project PTDC/EQU-FTT/102166/2008 and Ph.D. Grants SFRH/BD/74551/2010, SFRH/BD/70641/2010, and SFRH/BD/41562/2007 for M.L.S.B., C.M.S.S.N., and P.J.C., respectively.