Thermodynamic simulation of li2co3 aqueous solution under fixed co2 pressures

Highlights: • The Pitzer-Harvie approach was successfully applied for Li₂CO₃-H₂O solution properties. • The experimental data on solubility was described with good accuracy. • The dependence of the Li₂CO₃ solubility on CO₂ partial pressure was calculated. The simulation of the thermodynamic properties and phase equilibria in the Li₂CO₃-H₂O system was carried out on the basis of the experimental data obtained by potentiometry method in the previous work of the authors and literature data on liquidus. The molal Pitzer–Harvie model of the ionic interactions in the solution was applied. The goal function included pH and potentiometric experimental data for lithium carbonate in the solution, as well as liquidus data. The optimization refers to the temperature range (273–373) K and CO₂ partial pressure range (10⁻⁴–10⁻¹) MPa. The final set of model parameters consists of three values corresponding to the interaction between Li⁺ and CO₃²⁻ ions.