An innovative biochemical route to recover cobalt from lateritic mining waste

Anne-Gwenaelle Guezennec (1) , Agathe Hubau (1) , Douglas O. Pino-Herrera (1) , Catherine Joulian (1)

1 BRGM - Bureau de Recherches Géologiques et Minières (BRGM)

Cobalt (Co) and nickel (Ni) are two major components of lithium ion batteries, and their demand is expected to grow steadily over the next decade thanks to the increase of electric vehicles production. Around 60% of world’s Ni reserves are contained in lateritic ores which display also significant amount of Co [1]. The treatment of this type of ore requires costly metallurgical methods that generally incur high energy or reagent consumptions and expensive capital equipment costs [2]. Despite these economic constraints, the production of Ni and Co from laterites is constantly increasing owing to the exhaustion of sulfidic deposits as well as the increase in metal demand. Laterites deposits are mainly located in tropical regions and are characterized by the presence of two distinct horizons: (i) an upper limonite zone where Ni content usually varies between 1 and 2% with also significant presence of Co; (ii) a lower saprolite zone with Ni content varying between 3 and 5%. The saprolitic ore is usually treated via pyrometallurgical reduction whereas the limonitic ore is traditionally processed through Pressure Acid Leaching (PAL) which has often proven to be very costly, plagued with technical challenges. At this time, Ni produced from laterites mainly derives from saprolite ores, the associated limonite ores being usually stockpiled and considered as a mining waste. This stockpiled material represents a vast unlocked resource. Recent work demonstrated that Ni and Co could be extracted from limonite by using acidophilic bacteria in anoxic condition, mild acid (pH 1.8) and at ambient temperature (30°C). This method is called “reductive bioleaching” or “bioleaching in reverse gear” [3, 4]. H2020 CROCODILE research project is dedicated to the demonstration of innovative metallurgical options for the recovery of Co from primary and secondary sources. In the frame of CROCODILE, reductive bioleaching was applied to limonite from New Caledonia. The leaching mechanisms were investigated and optimised in order to design a demonstration at pilot scale.

Mots clés: mining waste; reductive bioleaching; laterite; nickel; Cobalt

Domaines: Génie des procédés

Anne-Gwenaelle Guezennec, Agathe Hubau, Douglas O. Pino-Herrera, Catherine Joulian. An innovative biochemical route to recover cobalt from lateritic mining waste. WasreEng2022 - 9th International Conference on Engineering for Waste and Biomass Valorisation, https://wasteeng2022.org/, Jun 2022, COPENHAGUE, Denmark. ⟨hal-03585664⟩