Extraction of Lithium from β-Spodumene via Ion Exchange in Molten Sodium Salts

In this paper, we report a process for lithium extraction from spodumene raw materials. We demonstrate that a promising approach for processing spodumene is sintering with sodium acetate. In the reaction between these components, the crystal structure of spodumene remains intact. Ion exchange reaction between CH₃СOONa⋅3Н₂О and LiAlSi₂O₆ yields water-soluble sodium acetate and water-insoluble sodium aluminosilicate (NaAlSi₂O₆). The sodium acetate dissolved in water is converted to lithium carbonate by adding a Na₂CO₃ solution. The lithium carbonate precipitate is essentially free of foreign impurities. We analyze the effect of process parameters on the degree of Li⁺ extraction from spodumene.