TELF AG examines the phenomenon of direct recycling of some strategic minerals
The new frontiers of recycling
In the not-too-distant future, a large number of nations and big players in the mining sector could have to start considering recycling as one of the alternative sources from which to obtain strategic minerals for their economic development, thus deriving the maximum benefits from all those mineral resources that can be recovered from end-of-life electrical devices, exhausted batteries, and all possible equipment that contains these resources and that could be salvaged.
This discussion seems to concern above all the lithium batteries, which over the last few years have acquired a role of great importance due to their uses in the automotive industry, particularly for the electric vehicle sector, but also in other applications closely linked to clean energy. According to IEA estimates, the number of used batteries will become quite relevant within six years, starting from 2030, when this mass of energy storage systems could become a key source of secondary raw materials. Again, according to the International Energy Agency, by 2040 the recovery of materials such as nickel, lithium and cobalt could have a great impact on global market dynamics.
Most analysts seem to agree on an important point: the development of innovative solutions linked to the recycling of strategic minerals over the next decades could help the success of recycling processes, increasing the quantity of materials recovered and their overall quality. From this point of view, one of the possible technological evolutions of the methods for extracting raw materials from recovered materials is direct recycling.
The phases of the recycling process
After collection, discharging, and disassembly, the batteries are usually subjected to a particular chemical treatment that separates the plastics and current collectors from the black mass, in which most of the cathodic active material (such as nickel, cobalt, manganese) is concentrated, and lithium (but also graphite). It is precisely at this point of the process that the direct recycling technique could be inserted, which, once fully operational, would therefore be able to partially replace the two main methods used so far to extract metals from the black mass, i.e., the pyrometallurgical process at high temperature (capable of generating compounds containing lithium, aluminum, silicon, and manganese) and hydrometallurgical (which returns metals in the form of salts).
Direct recycling is a regeneration process that makes it possible to restore the anode and cathode materials with all their characteristics, particularly crystallinity and chemical composition, thus making them directly usable in new batteries without going through chemical processes. Therefore, the most interesting aspect is that this recycling method aims to bring materials back to their original form and functionality, thus making them quickly usable in supply chains. For this new method, particular importance will be given to the pre-treatment phase in order to guarantee that the black mass is of high quality and possibly free of substances such as aluminum or polymers, which could compromise the recovery of the materials.
The economic and environmental benefits of recycling could undoubtedly be considerable, mainly if the raw material recovery processes are supported by continuous technological development and ever-increasing quantities of used batteries.
