Abstract
Looking for a better knowledge concerning water and ionic liquids (ILs) interactions, a systematic study of the activity coefficients of water in pyridinium, pyrrolidinium and piperidinium-based ILs at 298.2 K is here presented based on water activity measurements. Additionally, the study of the structural effects of the pyridinium-based cation is also pursued. The results show that non-aromatic ILs are interacting more with water than aromatic ones, and among the ortho, meta and para isomers of 1-butyl-methylpyridinium chloride, the ortho position confers a more hydrophilic character to that specific IL. The physical-chemistry of the solutions was interpreted based on dissociation constants, natural bond orbitals and excess enthalpies providing a sound basis for the interpretation of the experimental observations. These results show that hydrogen bonding controls the behavior of these systems, being the anion-water one of the most relevant interactions, but modulated by the anion-cation interactions.
Original language | English |
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Pages (from-to) | 93-100 |
Number of pages | 8 |
Journal | Fluid Phase Equilibria |
Volume | 414 |
DOIs | |
Publication status | Published - Apr 25 2016 |
Keywords
- Activity coefficient
- COSMO-RS
- Excess enthalpy
- Hydrogen bonding
- Water activity
ASJC Scopus subject areas
- Chemical Engineering(all)
- Physics and Astronomy(all)
- Physical and Theoretical Chemistry