The raw ore is crushed and separated both mechanically and via floatation. Next, the concentrate undergoes energy- and chemically intensive hot acid-roasting. This process sees concentrated spodumene powder roasted at 1050°C, cooled, mixed with sulfuric acid, and then re-roasted at 200°C to produce water-soluble Li2SO4.

Commonly, although not exclusively, spodumene is converted to lithium hydroxide, which typically enters the NMC battery supply chain. On the other hand, lithium carbonate often enters the LFP battery supply chain. Processing spodumene into both lithium carbonate and hydroxide is possible with the same initial steps:

i. Coarse refining of the contaminated lithium sulfate through hardness and metal removal,

ii. Concentration via evaporation, and

iii. Fine purification via high-total dissolved solids ion exchange polish.

Purified Li2SO4 is combined with sodium carbonate (Na2CO3) to produce battery-grade lithium carbonate. To produce battery-grade chemicals, the crystallization process must be preciously engineered and controlled, and coupled with solids separation and washing techniques. SUNKAIER delivers modular and automated packages to achieve battery-grade lithium carbonate with a single crystallization step, removing the need for costly and chemically intensive two-step crystallization.

Production of LiOH starts similarly with purified lithium sulfate combined with NaOH. The resulting solution is then fed to crystallizer. After the removal of Na2SO4, the resulting LiOH undergoes a two-step crystallization process with a MVR crystallizer to produce battery-grade lithium hydroxide. This technology’s forced-circulation systems are fully automated, with built-in self-cleaning to ensure reliability at optimal capacity. During both crystallization phases, mother liquor can be recycled to recover lost lithium.

Preparing high purity lithium carbonate which can be used for pharmaceutical applications, electronic grade crystals of lithium or to prepare battery-grade lithium metal. Lithium carbonate as commercially produced from mineral extraction, lithium-containing brines or sea water, in aqueous solution is used as a feedstock and reacted with carbon dioxide under pressure to form dissolved lithium bicarbonate. Impurities in the lithium carbonate feedstock are either solubilized or precipitated out. Dissolved impurities are physically separated from the lithium bicarbonate using an ion selective means, such as an ion exchange material, or by liquid--liquid extraction. Purified lithium carbonate is then precipitated.