Molecular dynamics study on the dissolution characteristics and cluster formation of Li2CO3 in supercritical water

Recycling lithium from electronic waste is the focus of current research on waste treatment and resource utili-zation, and environmentally friendly supercritical water technology is an important recycling method. It is necessary to study the dissolution and precipitation characteristics of lithium salt in supercritical water. In this paper, molecular dynamics (MD) and quantum mechanics (QM) were used to study the dissolution properties of Li2CO3 in supercritical water and the structure and properties of clusters. The potential mean force (PMF), radial distribution function (RDF), and coordination number (CN) showed that the solubility of Li2CO3 in supercritical water was more affected by temperature, and the trend was opposite to that of temperature, and the ion pairs in solution were mostly in CIP state. Cluster searches were performed for the cluster configurations and their distribution probabilities of CIP states in supercritical water. The electrostatic potential distribution and inter-molecular interactions of the initial cluster configuration in the supercritical solution of Li2CO3 are calculated by the QM method. In this study, the cluster configuration with a planar symmetry structure accounted for the largest proportion, and the lowest free energy was-431.86308400 a.u.