Across Europe, small scale deposits of critical materials and/or strategic elements, such as W, Li and Sn, are not viable to mine and process using the traditional large scale mining and processing technologies due to their geological characteristics. Project FAME (Flexible And Mobile Economic Processing Technologies, EC Horizon 2020 Grant Agreement No. 641650) was created in order to specifically address the technical and environmental challenges to the sustainable processing of low sulphide ores from pegmatites, greisens and skarns deposits. One of the deposits, Alvarrões-Gonçalo, is a Li pegmatite located at the Gonçalo pegmatite field (Central Portugal) that is being investigated on the scope of the concerned project. Currently, the pegmatites are only being exploited for ceramics, aggregates and ornamental purposes, however, there is exploitation potential for Li₂O-rich ores. Froth flotation is being tested to produce a lepidolite concentrate. Results showed the feasibility to obtain a Li₂O grade adequate for the metallurgical production of lithium compounds as Li₂CO₃. The lepidolite flotation rejects, normally stored in tailings dumps, are mainly composed by a mixture of feldspars, quartz and non-recovered lepidolite (though a very low content), which is, by itself, a very interesting raw material for ceramic purposes. Consequently, mining exploitation of lepidolite, as Li₂O ore, from pegmatite could comply with the standards of green mining, reaching an almost zero waste exploitation, as it can be accomplished in the case of the mineral processing of the Alvarrões-Gonçalo lithium ore. This basic scenario could be improved by applying froth flotation also for feldspars/quartz separation, aiming at obtaining a high content feldspars concentrate (floated) and a quartz product (non-floated): the feldspars concentrate can be used to produce blends with different ratios feldspars/quartz for sanitary ware and tiles and quartz for other uses, such as glasses and silica flour.

Critical raw materials, such as graphite and lithium metal oxides (LMOs), with a high supply risk and high economic importance are present in spent lithium-ion batteries (LIBs). The recovery and recycling of these critical raw materials from LIBs will contribute to the circular economy model, reduce the environmental footprint associated with the mining of these materials, and lower their high supply risk. The main aim of this paper is to present a separation process to recover graphite from black mass (BM) from spent LIB. Simultaneously, LMO and copper (Cu) and aluminum (Al) foils were also recovered as by-products from the process. The process used a combination of simple and/or low environmental footprint technologies, such as sieving, sink-float, citric acid leaching, and milling through ultrasound and soft attrition, to allow separation of the LIB valuable components. Three graphite-rich products (with purities ranging between 74 and 88 wt.% total carbon and a combined yield of 14 wt.%) with three different sizes (<25 µm, <45 µm, and <75 µm), Cu and Al foil fragments, and an LMO-rich precipitate product are delivered. The developed process is simple, using low temperatures and weak acids, and using affordable and scalable equipment available in the market. Its advantage over other LIB recycling processes is that it can be implemented, so to speak, “in your backyard”.

The Volume 5 published for IJMMME Journal.