(218c) Volumetric Properties and Modeling of the Binary Mixtures of Ethanol with Ionic Liquids [BMIM]Ac and [BMIM]Cl

Ionic liquids and their mixtures are under consideration for their utility as processing fluids for bio-based polymers of lignocellulosic materials. Volumetric properties of mixtures of two different ionic liquids, namely 1-butyl-3-methylimidazolium acetate ([BMIM]Ac) and 1-butyl-3-methylimidazolium chloride ([BMIM]Cl), with ethanol were determined in a variable-volume view-cell equipped with a motorized pressure generator. Continuous density data were generated from 10 to 40 MPa at temperatures ranging from 298 to 398 K. Mixtures compositions covered a wide range from 5 to 75 wt % ionic liquid. The density data were modeled using the Sanchez-Lacombe and Simha-Somcynsky Lattice-Fluid models. Derived thermodynamic properties such as the isothermal compressibility, isobaric expansivity, internal pressure, and for the first time the solubility parameters of these mixtures and their pressure dependent variations were evaluated. The effectiveness of these mixtures in dissolution and separation of lignocellulosic materials is being explored with softwood and hardwood species as well as woody biomass such as bamboo.