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

TL;DR

This study uses molecular dynamics simulations to analyze the dispersion and structural properties of amino acid-based ionic liquids in water, revealing their potential as effective solvents and their aggregation behavior at different concentrations.

Contribution

The paper introduces a force field for imidazolium-based amino acid ionic liquids and investigates their structural behavior in aqueous solutions through detailed MD simulations.

Findings

AAIL ions are well dispersed in water regardless of concentration.

Dilute solutions mainly contain ion pairs, while concentrated solutions form larger aggregates.

Aqueous AAIL solutions have promising solvent properties for chemical engineering.

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.