Abstract
With the rising demand for lithium-ion batteries, mining of lithium minerals and their refining to lithium chemicals has grown rapidly over the last years. At the same time, environmental impact and sustainability are increasingly important for lithium extraction from mineral sources to remain viable in the future. The conventional extraction of lithium from spodumene via calcination, acid roasting, leaching, purification and crystallisation achieves high lithium recoveries and lithium hydroxide purities but is also energy- and chemical-intense and produces large amounts of low-value by-products. Large proportions of spodumene ore are discarded as waste during mining and processing because of the strict quality specifications for spodumene concentrate imposed by the calcination step. Furthermore, melting and clinker formation during calcination can degrade lithium recovery from spodumene that has been partly altered to muscovite and cookeite. The presentation will illustrate strategies that address the above challenges, including improved understanding of calcination and the effect of alteration and low grades on lithium recovery, as well as an alternative extraction route that results in marketable by-products.