Abstract
The global lithium supply balance has been under pressure since the recent increase in demand for electric vehicles. Conventional techniques for lithium extraction from natural resources are solar evaporation and hard-rock mining, which both have their limitations in view of sustainability. The question arises whether these methods will suffice for a responsible supply to provide the necessary materials for the emerging green economy. While new technologies for the valorization of lithium from unconventional resources like geothermal brines, salt lakes and seawater are in the pipeline, they are yet to be proven on an industrial scale. Membrane technology, ion-exchange adsorption and electrochemical methods are the current focus of several players in the pilot stage of their announced lithium carbonate or hydroxide production process. These technologies have various advantages and disadvantages in terms of energy consumption, selectivity and process costs, and the optimal choice remains dependent on local factors such as brine composition, energy availability and reagent cost. There are currently several DLE projects in the pilot phase, which is a significant step towards more sustainable lithium supply. Proving the economic and technical viability of these methods for extracting lithium from unconventional sources would increase the amount of globally proven reserves while diversifying and de-risking the supply chain, which is currently heavily dominated by a small number of countries.