CONICET | Buscador de Institutos y Recursos Humanos

The growing market demand for lithium is mainly due to its use in the manufacture of batteries for electric or hybrid vehicles and portable equipment (smartphones, tablets, power tools, notebooks, etc.). Currently there is great interest in finding new sources of lithium and technologies for its utilization. Li-S batteries have received attention due to their theoretical high specific energy density, which is 3 to 5 times higher than Li-ion batteries. Unlike Li-ion batteries, whose main raw materials are lithium carbonate and lithium hydroxide, Li-S batteries have lithium chloride as their main raw material. The anode used in the composition of Li-S batteries is lithium metal, produced by the molten lithium chloride salt electrolysis process. The extraction of lithium from pegmatites such as spodumene, previously abandoned in the 1990s, as considered uneconomical, has been made possible due to the increase in prices, as well as the purity of lithium products produced from minerals bearing lithium. The main methods used for lithium recovery from spodumene ore include the sulfuric acid process, the alkaline process (lime or limestone as raw material) and the chlorination roasting process. Thermodynamic modelling using the HSC software 5.1 was conducted to predict different reactions that could occur during chlorination roasting of the spodumene/MgCl2+CaCl2 system. Lithium extraction from the solid obtained after the chlorination roasting was also investigated. The results of thermodynamic analysis provided a better understanding of the chlorination roasting process for lithium extraction. Metallurgical tests with mass ratio of 1:6 (spodumene:chlorides) and molar ratio of 2:1 (MgCl2:CaCl2) allowed the recovery of 95% of the lithium contained in the spodumene concentrate.