Solvatochromic polarity parameters for binary mixtures of 1-butyl-3-methylimidazolium acetate with water, methanol, and dimethylsulfoxide

Abstract

Solvatochromic polarity parameters (ETN, a, β, and π*) for binary mixtures of 1-butyl-3-methylimidazolium acetate-ionic liquid, which is a promising solvent of lignocellulosic materials with water, methanol, and dimethylsulfoxide, are determined via UV spectroscopy. A Redlich-Kister (CNIBS/R-K) equation modified for a quasi-ideal binary solvent is used to describe algebraically the dependences between the Dimroth-Reichardt energies, the Kamlet-Taft parameters, and the composition of binary mixtures. The addition of molecular solvents to the ionic liquid in significant amounts was shown to produce no radical changes in its polarity or donor and acceptor characteristics, due to the incorporation of a cosolvent into supramolecular clusters formed by alkylimidazolium cations.