Prediction of the component solubility in the ternary systems HClLiClH 2O, HClMgCl 2H 2O and LiClMgCl 2H 2O at 0 °C and 20 °C using the ion-interaction model

Abstract

Component solubility in HClLiClH 2O, HClMgCl 2H 2O and LiClMgCl 2H 2O systems of high ionic strength at 0°C and 20°C are calculated by using the Pitzer's ion-interaction model and parameters derived from a least-squares optimization procedure which couples activity coefficient with solubility data. Excellent agreement with experimental solubility for ternary mixtures indicates that the model can be successfully used to predict the component solubility of salt lake brine systems that contain high concentration of LiCl. For all of the systems containing a high concentration of HCl, measurements of the activities of the complex compounds are not available, hence the evaluation of the values for the mixing parameters θ MN and Ψ MNX relied on solubility data in subsystems. The prediction also indicates that the parameters used do not vary linearly with the temperature, thus the algorithm used in order to calculate the parameters of LiCl at different temperatures is presented here. Based on the predictions of the solubility, the solubility curves of six ternary systems are constructed.