(590b) Experimental Measurements of Ionic Liquid and Water Systems for Absorption Refrigeration

Absorption refrigeration cycles have many advantages over the traditional vapor-compression cycles. The addition of an ionic liquid working fluid to an absorption refrigeration system has the ability to overcome some of the safety and environmental impacts of the current working fluids in addition to the existing ability to replace electrical energy with low value heat energy. Many ionic liquids are completely miscible with water, which leads our focus to investigating ionic liquids and water for this application.

Thermodynamic measurements and/or predictive modeling must provide the mixture properties and phase behavior in order to evaluate these systems. Vapor-liquid equilibrium is used to determine activity coefficients, accounting for the mixture deviations from ideal behavior. In addition, excess enthalpies are used to determine the strength of interactions between water and the ionic liquid. We have previously presented three 1-ethyl-3-methylimidaolium based ionic liquids and water systems for the absorption refrigeration application. Here, we present a similar evaluation for several new ionic liquid and water systems.