(453b) Thermodynamic Modeling of Lithium Salt Systems with the Electrolyte NRTL Model
AIChE Annual Meeting
2017
2017 Annual Meeting
Engineering Sciences and Fundamentals
Thermophysical Properties and Phase Behavior II: Electrolytes and Ionic Liquids
Tuesday, October 31, 2017 - 3:34pm to 3:53pm
Thermodynamic models are essential to facilitate the advancement of process design, optimization, and operation range of absorption heat pumps and refrigeration units that utilize lithium salt systems. The objective of the present work is to continue working toward a comprehensive thermodynamic representation of lithium salt systems by implementing the symmetric electrolyte NRTL (eNRTL) activity coefficient model. This solubility model correlates the nonideality of the solution with the composition dependency by utilizing two binary interaction parameters for each of the electrolyte-electrolyte and molecule-electrolyte pairs in the system. Each parameter is determined by applying up to three temperature dependent coefficients and then regressed from experimental data. This allows the parameters to establish the accuracy of the model for concentrations up to saturation and temperatures between 273.15-473.15 K. The lithium chloride and water binary system has already been completed, therefore this work will focus on the binary systems containing lithium bromide, lithium iodide, and lithium nitrate with water.