Modelling the Na–K–Ca–Mg–Cl–SO₄ System

Researchers have developed a low temperature Pitzer model for the Na–K–Ca–Mg–Cl–SO₄ System. Pitzer models are useful in studying the behaviour of ions dissolved in aqueous solutions, which can have implications for living cells in the environment. The new model builds upon the team’s previous low-temperature model for the Na-K-Ca-Mg-Cl system, and includes additional data to accurately represent various salt systems. The model could be useful in the study of Cl-SO₄-rich brines on planetary bodies, which form as seawater is modified by evaporation or freezing. Ultimately, this information can provide insight into processes that affect habitability in such environments.

The study, “A Low-Temperature Aqueous Thermodynamic Model for the Na–K–Ca–Mg–Cl–SO₄ System Incorporating New Experimental Heat Capacities in Na₂SO₄, K₂SO₄, and MgSO₄ Solutions,” was published in the Journal of Chemical & Engineering Data. The work was supported through NASA’s Habitable Worlds Program. NASA Astrobiology provides resources for Habitable Worlds and other Research and Analysis programs within the NASA Science Mission Directorate (SMD) that solicit proposals relevant to astrobiology research.