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Global Outlook on the Availability of Critical Metals and Recycling Prospects from Rechargeable Batteries
Published in Abhilash, Ata Akcil, Critical and Rare Earth Elements, 2019
Pratima Meshram, B.D. Pandey, Abhilash
The common cobalt-bearing minerals found in economic deposits include erythrite, skutterudite, cobaltite, linnaeite, carrollite, and asbolite (asbolane). Cobalt is also found in chemical compounds often associated with sulfur and arsenic (Table 2.2). Though some cobalt is produced from metallic-lustered ores like cobaltite (CoAsS) and linnaeite (Co3S4), it is industrially produced as a byproduct of copper, nickel, and lead. While nickel laterites are mostly processed directly, other Co-bearing ores are beneficiated (by flotation or gravity methods) to produce concentrates, which are hydrometallurgically processed to extract cobalt (Shedd, 2004). Cobalt present as a byproduct of copper is concentrated (sulfides) and converted to oxides by roasting. The oxide is leached in sulfuric acid dissolving metals more reactive than copper, particularly Fe, Co, and Ni as sulfates. After removing iron as iron oxide, cobalt is precipitated as Co(OH)3, which is roasted and then reduced to cobalt metal with charcoal or hydrogen gas (Panayotova and Panayotov, 2014).
Leaching with Ferric and Cupric Ions
Published in C. K. Gupta, T. K. Mukherjee, Hydrometallurgy in Extraction Processes, 2019
The results of leaching carried out under standard conditions (temperature, 95°C; Fe3+ concentration, 150 g/1; H2SO4, 30 ml in 690 ml lixivant; solid weight, 47 g/690 ml lixivant; O2 flow rate, 1 l/min) are presented in Figure 4. It can be seen that 80% of the cobalt and 50% of the copper were extracted, and 50% of the copper was extracted within 24 h. The reaction was found to be strongly dependent on temperature. The increase of Fe3+ concentration and the introduction of O2 into the leach both contributed toward enhancement of the overall recoveries of cobalt from the ore. The apparent activation energy for the dissolution of cobaltite was found to be 5 kcal/mol. Studies on leaching of cobalt from sources other than cobaltite have also been reported. For example, DeCuyper38 reported the work he carried out to leach cobalt from carrollite (Co2CuS4) mineral specimens in both ferric sulfate solutions and bacterial leaching media. He suggested a similar leaching mechanism to that of cobaltite, as pointed out by Sutton and Corrick. The mineral carrollite was found to remain unattacked by bacterial solution alone. Even in ferric sulfate solution (60 g Fe3+/l), the rate of dissolution (2.6 mg/9 h) was quite slow. In investigations reported by Torma,68,69 it was, however, claimed that 86% of cobalt present in synthetic CoS could be leached out by bacterial leaching.
The Boléo Cu-Co-Zn deposit, Baja California Sur, Mexico: the role of magmatic fluids in the genesis of a synsedimentary deposit
Published in Adam Piestrzyński, Mineral Deposits at the Beginning of the 21st Century, 2001
A.G. Conly, S.D. Scott, H. Bellon, G. Beaudoin
In total there are eight mineralized ore beds, or mantos. The mantos occur within the claystone facies either in contact with or stratigraphically proximal to the conglomerate facies of the underlying fan-delta sequence. The mantos are comprised of a finely laminated claystone base (<2 m), overlain by a thin to thick (2-20 m) polymictic claystone breccia, and capped by an Mn-oxide-rich aminated claystone (<2 m; Fig. 2). Mineralization occurs as finely disseminated grains that occur along claystone laminae, within breccia matrix and fragments, and open-space infillings. The mineralization varies among sulphide-, oxide-, to mix sulphide-oxide-bearing facies. The oxides are products of surficial weathering. Sulphide facies contains pyrite + chalcocite + covellite + chalcopyrite ± bornite ± sphalerite. XRD analysis indicates the presence of Co-bearing sulphides carrollite and linnaeite. Oxide facies contains Mn-oxides, Fe-oxides, and a complex mixture of Cu-bearing oxides, although primary hydrothermal Mn-oxides co-exist with sulphide-rich mineralization. Gangue includes gypsum, calcite, montmorillonite, chalcedony, and volcanic fragments.
A Comprehensive Review on Cobalt Bioleaching from Primary and Tailings Sources
Published in Mineral Processing and Extractive Metallurgy Review, 2023
Alex Kwasi Saim, Francis Kwaku Darteh
Cobalt is extracted from a number of primary sulfide minerals, mainly carrollite (CuCo2S4), linnaeite (Co3S4) and cattierite (CoS2). Carrollite has been used in most of the studies to date on the bioleaching of these primary Co sulfide deposits. To offer proof of the interaction pattern between carrollite and microorganisms, bioleaching of high purity carrollite minerals with a mesophilic bacteria consortium was monitored using SEM/EDS analysis (Nkulu et al. 2015; Nkulu, Gaydardzhiev, and Mwema 2013). SEM examinations of pure carrollite revealed a gradual bacteria colonization of the mineral surface with time in the Co bioleaching process. However, it is revealed that the oxidation product layer (mainly composed of jarosite) formed on the surface of carrollite during bioleaching gradually increases, and the layer thickness can reach over 6 μm (Liu et al. 2017). According to Chen et al., cooperative bioleaching, including oxidation, generated by the bacteria adhered to the surface and Fe3+ re-oxidized by bacteria in suspension, was thought to be the driving force behind carrollite dissolution. From their study, 96.51% of Co was recovered from a low grade refractory carrollite after direct oxidation for 6 days at a pulp density of 10% (Chen et al. 2013). Activated carbon and surfactants have been shown to greatly increase the dissolution rate of carrollite, either independently or in combination (Liu et al. 2014, 2015a). Given the widespread presence of carrollite in key areas such as the Katanga polymetallic deposits, there is a significant motivation to make bioleaching a financially viable alternative for Co extraction. However, the bioleaching processes of carrollite must be better understood since the rate and degree of carrollite bioleaching can be crucial in Co extraction.