From lithium mineral to chemical: challenges and opportunities

About half of the global supply of lithium for the battery market is extracted from lithium minerals, such as spodumene. Conventional extraction of lithium from spodumene concentrate proceeds via calcination, acid roasting, leaching, purification and crystallisation of lithium hydroxide. The process achieves high lithium recoveries and lithium hydroxide purities but suffers from large energy, chemical and by-product footprints, as well as inflexibility to accommodate low grade sources or variations in concentrate mineralogy. The strict specifications for spodumene concentrate suitable for calcination result in large proportions of spodumene ore reporting to waste streams. Furthermore, common late-stage alteration of spodumene to muscovite and cookeite leads to partial melting and clinker formation during calcination, degrading lithium recovery from altered ore. With the recent focus on more sustainable production of energy and technology critical raw materials, the above challenges need to be addressed to keep lithium extraction from mineral sources viable in the future. The presentation will illustrate the challenges but also focus on opportunities to make lithium extraction more sustainable.