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The distribution coefficients of Co, Ni, Ag, Au, Pd, and Fe at low concentrations between liquid copper and molten white metal (low-iron copper matte, 'Cu2S') were investigated experimentally as a function of temperature (1250-1350°C) and SO2 partial pressure (0.01-1 atm). The experimental technique involved samples equilibration at controlled temperature and gas atmosphere, followed by quenching and subsequent elemental analysis of equilibrium phases with electron probe X-ray microanalysis and laser ablation-inductively coupled plasma-mass spectrometry. The distribution coefficient of silver, nickel, gold and palladium between liquid copper and white metal indicated that they favour the blister copper whereas cobalt and iron distribute more to the white metal. The distribution coefficient of nickel, e.g. increased from 2.1 at 0.1-1.0 atm PSO2 and 1250°C to 3.2 at 1350°C. The distribution coefficients were only slightly dependent on temperature. The relatively strong dependence of the distribution coefficient of cobalt on PSO2 was discussed. [ABSTRACT FROM AUTHOR]

Cobalt is a critical, high-value metal used extensively in batteries and other sustainable technologies. To secure its supply in future, it is utmost important to recover cobalt efficiently from industrial wastes and recycled End-of-Life batteries. This study aims at finding ways to improve the reduction of cobalt as well as valuable metals nickel and copper in nickel slag cleaning furnace conditions by using both traditional fossil-based coke and a more sustainable option, low-CO2 footprint biochar, as reductants. A cobalt-rich fraction of battery scrap (25.5 wt% Co) was also used as a secondary feed. The experimental technique consisted of reduction experiments with different times at 1400 ffiC under inert atmosphere, quick quenching and Electron Probe X-ray Microanalysis. The use of biochar resulted in faster reaction kinetics in the reduction process, compared to coke. Moreover, the presence of battery scrap had a clear impact on the behavior and reduction kinetics of the elements and/or enhanced settling and separation of matte and slag. The addition of scrap increased notably the distribution coefficients of the valuable metals but consequently also the iron concentration in matte which is the thermodynamic constraint of the slag cleaning process. [ABSTRACT FROM AUTHOR]

Recycling of metals from different waste streams must be increased in the near future for securing the availability of metals that are critical for high-tech applications, such as batteries for e-mobility. Black copper smelting is a flexible recycling route for many different types of scrap, includingWaste Electrical and Electronic Equipment (WEEE) and some end-of-life energy storage materials. Fundamental thermodynamic data about the behavior of battery metals and the effect of slag additives is required for providing data necessary for process development, control, and optimization. The goal of our study is to investigate the suitability of black copper smelting process for recycling of battery metals lithium, cobalt, manganese, and lanthanum. The experiments were performed alumina crucibles at 1300 °C, in oxygen partial pressure range of 10-11-10-8 atm. The slags studied contained 0 to 6 wt% of MgO. Electron probe microanalysis (EPMA) and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) techniques were utilized for phase composition quantifications. The results reveal that most cobalt can be recovered into the copper alloy in extremely reducing process conditions, whereas lithium, manganese, and lanthanum deport predominantly in the slag at all investigated oxygen partial pressures. [ABSTRACT FROM AUTHOR]

One possible way of recovering metals from spent lithium-ion batteries is to integrate the recycling with already existing metallurgical processes. This study continues our effort on integrating froth flotation and nickel-slag cleaning process for metal recovery from spent batteries (SBs), using anodic graphite as the main reductant. The SBs used in this study was a froth fraction from flotation of industrially prepared black mass. The effect of different ratios of Ni-slag to SBs on the time-dependent phase formation and metal behavior was investigated. The possible influence of graphite and sulfur contents in the system on the metal alloy/matte formation was described. The trace element (Co, Cu, Ni, and Mn) concentrations in the slag were analyzed using the laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) technique. The distribution coefficients of cobalt and nickel between the metallic or sulfidic phase (metal alloy/matte) and the coexisting slag increased with the increasing amount of SBs in the starting mixture. However, with the increasing concentrations of graphite in the starting mixture (from 0.99 wt.% to 3.97 wt.%), the Fe concentration in both metal alloy and matte also increased (from 29 wt.% to 68 wt.% and from 7 wt.% to 49 wt.%, respectively), which may be challenging if further hydrometallurgical treatment is expected. Therefore, the composition of metal alloy/matte must be adjusted depending on the further steps for metal recovery. [ABSTRACT FROM AUTHOR]

Since the current volumes of collected end-of-life lithium ion batteries (LIBs) are low, one option to increase the feasibility of their recycling is to feed them to existing metals production processes. This work presents a novel approach to integrate froth flotation as a mechanical treatment to optimize the recovery of valuable metals from LIB scrap and minimize their loss in the nickel slag cleaning process. Additionally, the conventional reducing agent in slag cleaning, namely coke, is replaced with graphite contained in the LIB waste flotation products. Using proper conditioning procedures, froth flotation was able to recover up to 81.3% Co in active materials from a Cu-Al rich feed stream. A selected froth product was used as feed for nickel slag cleaning process, and the recovery of metals from a slag (80%)–froth fraction (20%) mixture was investigated in an inert atmosphere at 1350 °C and 1400 °C at varying reduction times. The experimental conditions in combination with the graphite allowed for a very rapid reduction. After 5 min reduction time, the valuable metals Co, Ni, and Cu were found to be distributed to the iron rich metal alloy, while the remaining fraction of Mn and Al present in the froth fraction was deported in the slag. [ABSTRACT FROM AUTHOR]

In electrolytic production of zinc, the iron levels in the solutions are controlled by precipitation of jarosite or goethite. These precipitates also co-precipitate unrecovered valuable metals (Zn, Pb, Cu, Ag) as well as elements of concern (As, Cd, Hg). After stabilization, the residues are traditionally landfilled. This work investigates pyrometallurgical treatment of jarosite residue to convert the material into reusable clean slag and to recover the valuable metals within the residue. The pyrometallurgical treatment is divided into two functional steps. First, the material is melted in an oxidizing atmosphere, after which the oxide melt is reduced to produce an inert, clean slag. Then, a liquid metal or speiss phase collects the valuable metals, such as silver. The aim was to examine the optimal process conditions for reaching the target values for remaining metals in the slag; Pb < 0.03 wt %, Zn < 1 wt %. As a conclusion, the limiting factor in sulfur, lead, and zinc removal is the contact between the oxidizing or reducing gas and the molten sample. The mass transfer and volatile metals removal were significantly improved with a gas lance installation. The improved gas-liquid interaction enabled the first steps of gas flow rate optimization and ensured the sufficiently low end-concentrations of the aforementioned elements. [ABSTRACT FROM AUTHOR]

The equilibrium phase relations of the CaO–SiO 2 –TiO 2 –Al 2 O 3 –MgO system were investigated experimentally in air at 1250–1400 °C using a high-temperature equilibration/quenching technique, followed by direct phase analysis by scanning electron microscopy equipped with X-ray energy dispersive spectroscopy. The equilibrium solid phases of silica, rutile, and pseudobrookite solid solution were found to coexist with the liquid phase. The 1300–1400 °C isothermal sections were constructed based on the experimentally measured liquid compositions. The experimental results were compared with simulations using MTDATA and FactSage thermodynamic software and their databases. This study provides guidelines for the selective crystallization of pseudobrookite from titania-bearing slag. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel fluxing strategy was proposed for trace metals recycling from e-waste through copper matte smelting. • Ag and Ni can be efficiently recovered into matte at all conditions. • Sn markedly vaporized into gas and Co deported predominantly into slag and spinel. • Spinel saturation in slag favored greater deportment of Ag and Ni into matte than at silica saturation. • Dissolutions of trace elements in spinel-saturated slag were smaller than at silica saturation. The distribution behavior of trace metals between copper matte and spinel-saturated iron silicate slags was investigated at 1250 °C and p SO 2 of 0.25 atm at low silica concentrations. The experiments were conducted in magnetite (Fe 3 O 4) spinel crucibles in controlled CO-CO 2 -SO 2 -Ar gas mixtures using a high-temperature equilibration-quenching technique. The concentrations of trace elements in matte, spinel, and slag were quantified by electron probe X-ray microanalysis and laser ablation-inductively coupled plasma-mass spectrometry. The trace metals (Ag, Ni, Co, and Sn) in all phases and their distribution coefficients were calculated as a function of matte grade. Results show that silver and nickel can be effectively recovered into matte, whereas cobalt and tin are predominantly deported into slag and gas phases, respectively. These results augment the fundamental thermodynamic data of trace metal distributions in copper smelting processes at low-silica fluxing practices. [ABSTRACT FROM AUTHOR]

[Display omitted] • Experimental study on recycling WEEE through copper smelting. • Ag can be effectively recovered into copper alloy at all conditions. • Co and Ni favored the solid phases compared to their dissolution in slags. • Ni and Sn were concentrated in copper alloy at lower P O2 but in slag at higher P O2. • Higher temperatures and lower P O2 favor the deportment of trace elements into the copper alloy. Recycling of waste electrical and electronic equipment (WEEE) is attracting increasing attention, due to the presence of valuable metals and the risk of environmental emissions associated with WEEE disposal. In this study, the distributions of trace elements (Ag, Ni, Co, and Sn) between copper alloy and magnetite/wüstite-saturated iron silicate slags were investigated at 1200–1300 °C and P O2 of 10-10-10-6.5 atm, simulating the conditions of WEEE reprocessing through secondary copper smelting and converting. The high-temperature isothermal equilibration experiments were conducted in synthesized magnetite/wüstite crucibles under controlled CO-CO 2 atmospheres followed by quenching in an ice-water mixture. The phase compositions and concentrations of the trace elements in copper alloy, magnetite/wüstite, and slag were determined by Electron Probe X-ray Microanalysis and Laser Ablation-High-Resolution Inductively Coupled Plasma-Mass Spectrometry. The distribution coefficients of all investigated trace elements between copper alloy and slag increased with decreasing oxygen partial pressure and increasing temperature. Ag distributed strongly into the copper alloy at all conditions, whereas Co mainly deported into the slag phase. Ni and Sn were concentrated in the alloy at lower P O2 and in the slag at higher P O2. Varying concentrations of Ni, Co, and Sn were also dissolved into the solid magnetite/wüstite phase. [ABSTRACT FROM AUTHOR]

This current study addresses the role of copper and aluminum - typical major components of current collector scrap from battery manufacturing plants - in the leaching of pre-treated LiCoO 2 -rich battery waste concentrate at industrially relevant process conditions (T = 60 °C, [H 2 SO 4 ] = 2 M, S/L = 200 g/L). An empirical model has been constructed which demonstrates that the effects of both copper and aluminum are significant. Both elements have independent and linear impacts on cobalt extraction and acid consumption. The model predicts that either 11 g of copper (0.75 Cu/Co, mol/mol), 4.8 g of aluminum (0.7 Al/Co, mol/mol) or a combination of both are required for full cobalt extraction from 100 g of sieved industrial battery waste concentrate. Aluminum was shown to influence cobalt leaching although it was less effective (47%) when compared to copper (66%) in terms of current efficiency due to associated side reactions, such as excess H 2 formation. Aluminum has several possible reaction routes for LiCoO 2 reduction; in parallel or in series via H 2 formation, Cu2+ cementation and/or Fe3+ reduction, whereas copper acts solely through Fe3+ reduction. These results indicate that by using copper scrap, in preference to the more typical hydrogen peroxide, the CO 2 footprint of the battery leaching stage could be decreased by at least 500 kg of CO 2 per ton of recycled cobalt. In contrast, the use of aluminum, although promising, is less attractive due to the challenges related to its removal during subsequent solution purification. • Industrial processed cobalt-rich waste battery concentrate was leached in acid. • Aluminum and copper scrap current collector foils were used as reductants. • Effects of reductants on leaching efficiency were assessed by regression modeling. • Both copper and aluminum enhanced the dissolution of cobalt, nickel and manganese. • The interaction between copper and aluminum was found to be insignificant. [ABSTRACT FROM AUTHOR]

A potential industrial waste-waste co-treatment process was proposed and verified for the recovery of the valuable metals Co, Ni, and Cu from copper smelting slag by utilizing high temperature SO 2 off-gas. Sulfation roasting followed by water leaching under designed thermodynamic conditions was conducted to facilitate the selective formation of Co, Ni, and Cu sulfates while separating iron as oxide. Several parameters were studied such as roasting temperature, roasting time, the addition of Na 2 SO 4 , and leaching agent. Under the optimized sulfation roasting conditions (Gas flow: 500 mL/min, 5% SO 2 + 20% O 2 + 75% Ar; Roasting temperature: 650 °C; Roasting time: 4 h; Addition of Na 2 SO 4 : 30%) followed by water leaching (Leaching temperature: 80 °C; Leaching time: 5 h; solid to liquid ratio: 0.05 g/mL), the extraction yields of Ni, Co, and Cu were shown to reach 95.8% and 91.8%, 81.6%, respectively. Furthermore, the sulfation roasting – water leaching process was confirmed on lab-scale as a feasible and efficient way to recover valuable metals and the mechanism was determined and verified from the microstructural evolution. Finally, a potential environmentally friendly industrial process in terms of the energy flow and material flow was presented based on preliminary assessments for environmental benefits, economic benefits, and heat recovery. [Display omitted] • An industrial waste-waste co-treatment process was proposed to recover Co, Ni, and Cu from copper smelting slag. • Reaction mechanism of the proposed sulfation roasting by water leaching process was experimentally defined and verified. • The extraction yields of Ni, Co, and Cu can reach 95.8% and 91.8%, 81.6%, respectively under the optimized condition. • A potential environmentally friendly industrial process referred to the energy flow and material flow was presented. [ABSTRACT FROM AUTHOR]