Lithium

Lime is used during the processing of solution brines and mineral ores to produce lithium carbonate and lithium hydroxide, essential for the manufacturing of rechargeable batteries for electric vehicles and other devices, as well as in the manufacturing of ceramics, glass, greases and metallurgical powders.   

Magnesium, silica and aluminium are common solution impurities in lithium processing from brines, that cannot readily be removed by evaporation. Lime is used to react with and remove these impurities from process solution as precipitates. 

Lithium-containing spodumene mineral ore, is typically upgraded to a spodumene concentrate (SC6) containing 6% Li₂O via flotation. The spodumene concentrate can be treated via an acid roasting process or an alkaline (using Na₂CO₃) leach method to produce the final lithium product. Both process routes use lime. 

In the acid-based process, lime is used to neutralize acid and remove magnesium, while in the alkaline leach process lime is used to convert lithium carbonate to lithium hydroxide.   

The conversion of insoluble lithium carbonate into soluble lithium hydroxide is required in some lithium processing flow sheets and is achieved by reacting lithium carbonate with lime to form precipitated calcium carbonate and lithium hydroxide.  

Calcium carbonate is separated from soluble lithium hydroxide that is further purified and crystalized as lithium hydroxide monohydrate (LHM), LiOH.H₂O.