Lithium Behavior in Salt-water System Explored by Molecular Dynamics Simulation

Abstract

The molecular dynamics simulation method was adopted to study the transient characteristics of Li⁺, CO₃ ²⁻, and SO₄ ²⁻ in Na⁺, K⁺, Li⁺, Cl⁻, and SO₄ ²⁻/H₂O system. The composition of Na⁺, K⁺, Li⁺, Cl⁻, SO₄ and CO₃ was selected to optimize the initial structural model and conduct dynamic simulation. The mean azimuth shift and diffusion coefficient of Li⁺, CO₃ ²⁻, and SO₄ ²⁻ in the system, the radial distribution function and potential energy between Li⁺ and −OW, SO₄ ^{2 −} and −OW as well as CO₃ ^{2 −} and −OW, and the dielectric constant of hydrogen bond were expounded and analyzed. At the same time, the Li enrichment behavior in the evaporation process of salt lake brine was analyzed based on the simulated data. The results show that the simulation results are in good agreement with the experimental values, which verifies that, compared with other ions, the crystallization of Li⁺ and SO₄ ²⁻ occurs earlier after reaching saturation.

Keywords

salt lakes Li⁺ / CO₃ ²⁻ / SO₄ ²⁻ / MD / salt water system