Aqueous Solutions of Amino Acid Based Ionic Liquids. Dispersion and Structure

Abstract

New ionic liquids (ILs) are continuously introduced involving an increasing number of organic and inorganic ions. Amino acid based ILs (AAILs) represent a specific interest due to their natural origin and, allegedly, low cost. We apply our recently developed force field for imidazolium-based AAILs to investigate structure properties in their aqueous solutions via molecular dynamics (MD) simulations. By reporting cluster analysis, radial distribution functions and spatial distribution functions, we argue that AAIL ions are well dispersed in the aqueous media, irrespective of the AAIL content. Aqueous solutions of AAILs exhibit desirable properties as solvents for chemical engineering. The AAILs in relatively dilute aqueous solutions (10 mol% AAIL) exist as ion pairs, while more concentrated solutions feature certain amount of larger ionic aggregates.