Search

The recycling of used lead–acid batteries is currently the main source of lead in the world. More than 50% of the weight of a used lead–acid battery is battery paste, in which lead occurs in compounds with oxygen and sulfur. In pyrometallurgical processes of battery paste, coke or coke breeze is used as a traditional additive acting as a fuel/reducer. Due to the constantly high prices of these materials, research is being carried out to find alternative (equally efficient but cheaper) carbon-bearing materials. Those materials can be technological replacements for coke or coke breeze in pyrometallurgical processes. The aim of the presented work was to check the possibility of using fine-grained carbon-bearing materials, in the form of anthracite dust and coal flotation concentrate, for battery paste processing, as replacements for traditionally used coke and coke breeze. As part of the presented work, the following tests were carried out: thermogravimetric tests using battery paste, processes of smelting battery paste in a pit furnace, and processes of smelting battery paste in a rotary furnace. The research results indicate that fine-grained carbon-bearing materials, in the form of anthracite dust and coal flotation concentrate, can be successfully used as a replacement for traditionally used fuels/reducers. [ABSTRACT FROM AUTHOR]

Copyright of Nonferrous Metals (Extractive Metallurgy) is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The paradigm shift toward the closed‐loop recycling of spent lithium‐ion batteries necessitates the direct, efficient cathode recovery that goes beyond the traditional pyrometallurgy and hydrometallurgy techniques, meanwhile avoiding substantial energy consumption, tedious procedures, or chemical contamination. In this study, a straightforward, dual‐functional upcycling approach is presented for the spent nickel‐rich cathodes to boost their high‐rate performance. Specifically, the protocol rationally employs the Li vacancy within the degraded oxide to minimize the La diffusion barrier, expanding the lattice spacing of the layered structure; the Li+ conductive, conformal LiLaO2 encapsulation further suppresses the interfacial acid corrosion and structural deterioration into the rock‐salt phase. Transmission‐mode X‐ray diffraction tracks the reversible lattice breathing of the regenerated cathode in operando, suggesting the continuous, kinetically boosted solid‐solution process with all the microcracks repaired. The as‐assembled regenerated LiNi0.8Co0.1Mn0.1O2/Graphite pouch cell (1.4Ah) thus achieves 91.0% capacity retention for 500 cycles, the energy density of 277 Wh kg−1 as well as extreme power output of 1030 W kg−1 at the cell level. This upcycling strategy paves the way for value‐added utilization of the retired Ni‐rich cathodes in practical high‐rate battery prototypes. [ABSTRACT FROM AUTHOR]

The global smelting business of nickel using rotary kilns and electric furnaces is expanding due to the growth of the secondary battery market. Efficient operation of electric furnaces requires consistent calcine temperature in rotary kilns. Direct measurement of calcine temperature in rotary kilns presents challenges due to inaccuracies and operational limitations, and while AI predictions are feasible, reliance on them without understanding influencing factors is risky. To address this challenge, various algorithms including XGBoost, LightGBM, CatBoost, and GRU were employed for calcine temperature prediction, with CatBoost achieving the best performance in terms of MAPE and MLSE. The influential factors on calcine temperature were identified using SHAP from XAI in the context of the CatBoost model. SHAP effectively assesses model impacts, accounting for variable interdependencies, and offers visualization in high-dimensional contexts. Given the correlation and dimensionality of variables predicting calcine temperature, SHAP was preferred over Feature Importance or PDP for the analysis. By incorporating seven out of twenty operational factors like burner fuel and reductant feed rate, combustion conditions inside of the rotary kiln and RPM, the calcine temperature increased from 840 °C in 2023 to 910 °C by October 2024, concurrently reducing the electricity unit consumption of the electric furnace by 7.8%. Enhancements to the CatBoost algorithm will enable the provision of guidance values after optimizing key variables. It is expected that managing the rotary kiln's calcine temperature according to the predictive model's guidance values will allow for autonomous operation of the rotary kiln through inputting guidance values to the PLC. [ABSTRACT FROM AUTHOR]

Though indium has been removed from the fifth list (2023) of critical raw materials for the European Union list of critical metals, its recovery is still of paramount importance due to its wide use in a series of high-tech industries. As its recovery is closely associated with zinc mining, the recycling of In-bearing wastes is also of interest, for both profitable and environmental reasons. With unit operations (in hydrometallurgy and pyrometallurgy or extractive metallurgy) playing a key role in the recycling of indium, the present work reviewed the most recent innovations (2024) regarding the use of these operations in the recovery from this valuable metal from different solid or liquid wastes. [ABSTRACT FROM AUTHOR]

Copyright of Precious Metals / Guijinshu is the property of Precious Metals Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Online monitoring of lanthanide fission product concentrations has been a great challenge in the pyrochemical reprocessing of spent nuclear fuels. Electrochemical techniques, with the advantages of accuracy and timeliness, provide a feasible strategy. In this work, the relationship between lanthanum ion (La(III)) concentration and reaction current was investigated by various electrochemical methods in LiCl–KCl eutectic salt. Tafel test results show that there is a linear relationship between the exchange current density (i0) and ion concentration (i0 = 0.06618x + 0.04409). In addition, according to the comparative analysis of electrochemical test results, it is found that anodic stripping voltammetry is a potential ion concentration detection technology. The peak current (ipc) and ion concentration satisfy the relationship: ipc = 0.08503x − 0.02245. According to the equation, the calculated La(III) concentration is almost consistent with that analyzed by inductively coupled plasma atomic spectrometer (ICP-AES), which provides a plausible way for ion concentration monitoring in high-temperature molten salt. [ABSTRACT FROM AUTHOR]

Address to poor adaptability of traditional smelting methods to raw materials like bismuth concentrate, especially unsuitable for low-grade bismuth concentrate, low comprehensive recovery rate of valuable metals, difficult treatment of low concentration SO2 produced by pyrometallurgy, and high cost, a new process for separating molybdenum, tungsten, sulfur and bismuth by pressure oxidation alkaline leaching was proposed using low grade bismuth polymetallic concentrate of Shizhuyuan as raw material. The effects of alkali dosage, time, temperature, total pressure and liquid-solid ratio on the leaching rate of molybdenum, tungsten, sulfur and bismuth were studied. Under the optimum conditions, the leaching rate of molybdenum, tungsten and sulfur is 99.73%, 90.81% and 97.69% respectively, while bismuth remains un-leached and is enriched in the slag, which realizes the efficient separation of molybdenum, tungsten, sulfur and bismuth in low-grade bismuth polymetallic concentrates. [ABSTRACT FROM AUTHOR]

Copyright of Hydrometallurgy of China is the property of Hydrometallurgy of China Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Display omitted] The microstructure of the electrocatalyst plays a critical role in the reaction efficiency and stability during electrochemical water splitting. Designing an efficient and stable electrocatalyst, further clarifying the synthesis mechanism, is still an important problem to be solved urgently. Inspired by the copper pyrometallurgy theory, an exceptionally active NiMo/CF(N) electrode, consisting of an ant-nest-like copper foam substrate (defined as CF(N)) and deposited NiMo layer, was fabricated for the alkaline hydrogen evolution reaction (HER). Our findings expounded the structure construction mechanism and highlighted the pivotal role of the spatial occupancy of sulfur atoms in the construction of the ant-nest-like structure. The NiMo/CF(N) composite, characterized by channels with a 2 μm diameter, showcases strong electronic interactions, increased catalytic active sites, enhanced electron/ion transport, and facilitated gas release during HER. Remarkably, NiMo/CF(N) demonstrates ultralow overpotentials of 21 mV to deliver a current density of 10 mA cm−2 in 1 M KOH. This electrode also exhibits outstanding durability, maintaining a current density of 200 mA cm−2 for 110 h, attributed to the chemical and structural integrity of its catalytic surface and the excellent mechanical properties of the electrode. This work advances the fundamental understanding of constructing micro/nano-structured electrocatalysts for highly efficient water splitting. [ABSTRACT FROM AUTHOR]

• CaCl 2 is an additive suitable for pyrometallurgical recovery of spent LIBs. • CaCl 2 has good chlorination ability and slag optimization ability. • SiO 2 and CO 2 in the system contribute to the increase in HCl yield. The difficulty of separating Li during pyrometallurgical smelting of spent lithium-ion batteries (LIBs) has limited the development of pyrometallurgical processes. Chlorination enables the conversion of Li from spent LIBs to the gas phase during the smelting process. In this paper, the effects of four solid chlorinating agents (KCl, NaCl, CaCl 2 and MgCl 2) on Li volatilization and metal (Co, Cu, Ni and Fe) recovery were investigated. The four solid chlorinating agents were systematically compared in terms of the direct chlorination capacities, indirect chlorination capacities, alloy physical losses and chemical losses in the slag. CaCl 2 was better suited for use as a solid chlorinating agent to promote Li volatilization due to its excellent results in these indexes. The temperature required for the release of HCl from MgCl 2 , facilitated by CO 2 and SiO 2 , was lower than 500 °C. The prematurely released HCl failed to participate in the chlorination reaction. This resulted in approximately 12 % less Li volatilization when MgCl 2 was used as a chlorinating agent compared to when CaCl 2 was used. In addition, the use of KCl as a chlorinating agent decreased the chemical dissolution loss of alloys in the slag. The performance of NaCl was mediocre. Finally, based on evaluations of the four indexes, recommendations for the selection and optimization of solid chlorinating agents were provided. [ABSTRACT FROM AUTHOR]

Nickel is a strategic element whose production and consumption in over a decade has increased to over 39% and 71%, respectively. Generally, due to their complex mineralogy, laterites, the current attractive source of Ni, are subjected to hydrometallurgy and pyrometallurgy techniques without enrichment in order to extract Ni. Therefore, numerous investigations in vogue on laterite enrichment performed spanning from 1964 to date were reviewed in this article, and the future directions were proposed through critical synthesis. The possibilities of obtaining both higher recoveries and increase in grade for Ni were noticed using selective comminution-classification method followed by flocculation-flotation strategy. Hence, in order to improve on the reported Ni yields from selective comminution-classification process, one of the ways could be to subject the ore to a multi-stage selective comminution-classification method followed by subjecting the obtained concentrate to flocculation-flotation technique. Therefore, the findings of this investigation would aid in upscaling the production to meet the demand. Properties of goethite and serpentine were explored. Physical and flotation methods for laterite enrichment were reviewed. Future directions for laterite beneficiation were proposed. [ABSTRACT FROM AUTHOR]

This article investigated the recoverability of the Ga in bauxite by carbothermal reduction. Currently, Ga is mostly manufactured from bauxite through the Bayer process as a by-product of alumina, but it is worthwhile to consider alternative processes under stricter environmental regulations and a shortage of high-quality bauxite. This study focused on the Pedersen process, which is the alumina production process consisting of carbothermal reduction and alkaline leaching. The metal and slag phases were prepared by carbothermal reduction of bauxite at 1873 K, and then aluminium in the slag was leached with (Na2CO3 + NaOH) solution at 348 K. Evaluation by inductively coupled plasma atomic emission spectroscopy and inductively coupled plasma mass spectrometry revealed that almost all Ga in bauxite was transferred to the metal phase, and the distribution to the slag phase was negligible in carbothermal reduction, which agrees with the thermodynamic consideration. These results suggest that the gallium recovery from pig iron is necessary to produce Ga in the Pedersen process. [ABSTRACT FROM AUTHOR]

With the increasing usage rates of lithium ion batteries used in energy storage, the management of the resulting waste has also increasingly important. The short lifespan of lithium ion batteries and the precious metals they contain require careful management of these wastes from a technical, environmental and economic perspective. Therefore, in the context of the recovery of precious metals such as cobalt from waste lithium ion batteries, in this article, literature studies on the recovery of cobalt from commonly sed types of lithium ion batteries in the form of Nickel Manganese Cobalt and Lithium Cobalt Oxide have been evaluated. The literature review shows that the most commonly used methods are hydrometallurgical, pyrometallurgical and direct recovery methods. As the demand for lithium ion batteries increases in the coming years, the need to develop and optimize innovative methos for cobalt recovery will become even more important in achieving sustainability goals within energy storage systems. [ABSTRACT FROM AUTHOR]

During copper matte smelting, a lag exists in the analysis of the smelting results, leading to the production parameters not being effectively adjusted in time. As the first smelting process in copper pyrometallurgy, the optimization of the amount of raw material, as well as the prediction and adjustment of slag and matte phases, has become an extremely important step. To address this issue, this study analyzed copper smelting parameters, such as the copper content in the slag, matte grade, slag ratio, and Fe/SiO2 ratio. The Bayesian optimization support vector regression (BO-SVR) model was used to predict the copper content in the slag and matte grade by combining plant production data with machine learning. The data features of the relevant copper smelting parameters were extracted using the BO-SVR model, and the data were fitted to obtain the interaction relationship functions between the variables. The relationships between several variables in the copper smelting process were interpreted in combination with a theoretical analysis and applied in practice. The results showed that the model's prediction of melting results resolves the issues of lagging and adjustment of the smelting process. The model can provide insights for the analysis and adjustment of critical parameters in the smelting process and promote the development of intelligent analysis and control of copper matte smelting. [ABSTRACT FROM AUTHOR]

Nickel-based single-crystal superalloys are designed for extreme conditions due to their superior corrosion and creep resistance properties. However, these pose challenges in the subsequent recycling after reaching their end-of-life. Molten magnesium (Mg) can rapidly corrode the stable spent nickel-based superalloys and selectively dissolve nickel (Ni). This waste-free process represents an effective method for recycling spent superalloys and accomplishing metal regeneration. This study investigates the mechanism of selectively dissolving Ni from DD5, a nickel-based single-crystal superalloy, by optimizing process temperature, time, and Mg content in an inert atmosphere. Vacuum distillation was employed to separate the resulting Mg, residual superalloy (i.e., the material left post-extraction), and Ni-rich alloy (i.e., the metal product selectively extracted). The findings revealed that the residual superalloy after selective Ni dissolution is characterized by a porous skeleton structure with pore sizes predominantly ranging from 2 to 30 nm and a low compressive strength which is 1/10 of the original DD5 superalloy.

The aim of lithium-ion battery (LiB) recyclers is to create a closed-loop process to recover and reuse all the material as secondary sources of material to manufacture new batteries. Global LiB recycling companies apply pyrometallurgy, hydrometallurgy, or direct recycling to meet this goal. Pyrometallurgy is very energy intensive, but hydrometallurgy requires a pretreatment process and a new version of direct recycling that shows more promise for automation would also require pretreatment. Currently, recycling companies appear to favor hydrometallurgy. This review summarizes the current state of development of the pretreatment process involving battery discharging and mechanical treatment series from the literature and its application in the industry, with particular attention on Asia Pacific recyclers. The key pretreatment steps of battery discharging and mechanical treatment are the focus of this review, but pretreatment of the black mass containing cathode material prior to leaching is also included. Discharging is important to reduce the risk of fire during mechanical treatment. An interesting finding is that despite promising laboratory results, there has been no reported commercial application of battery discharging using the submersion method in an electrolyte solution. An efficient mechanical treatment of discharged batteries is essential to remove the impurities which could adversely impact the subsequent LiB processing. Research into mechanical treatment should also include a method to evaluate the liberation of material. This review has highlighted a new potential flowchart for recycling of various cathode types of LiBs. [ABSTRACT FROM AUTHOR]

In this paper, results of research on the reactivities of selected biomass types considering their application in pyrometallurgical processes of metal production are presented. Walnut shells, sunflower husk pellets and spent coffee grounds were selected as biomass materials. Their use as potential reducers in the process of metallurgical slag decopperisation is an innovative approach to this subject. The thermogravimetric findings show that all three tested biomass types are classified as highly reactive. The time to reach maximum reactivity ranges from 1.5 to 3 min and, the lowest value is recorded for the sample of spent coffee grounds. The sample hold time of two hours enables copper content reduction to approx. 1 wt% for practically all the reducers tested. A longer duration of liquid slag contact with the reducer results in a decreased copper content in the slag to a value below 1 wt%. Copper concentrations of 0.5 wt% and lower are observed with a hold time of 4 h. The preliminary results indicate that there is great potential for the use of this type of material in non-ferrous metallurgy, which may translate into replacing fossil raw materials and thus introducing the principles of a sustainable process in this case of metal production. [ABSTRACT FROM AUTHOR]

The electron beam cold hearth melting (EBCHM) process is one of the key processes for titanium alloy production. The unique characteristic of this pyrometallurgy process is the application of the cold hearth, which is responsible for controlling the Low-Density Inclusions (LDIs) and High-Density Inclusions (HDIs) in the melt. As a key process of inclusion removal, the information such as melt residence time in the cold hearth is directly related to the control of metallurgical defects in the ingot, and may also affect the composition distribution of the ingot. In this paper, the details for the physical phenomena, namely the evolution of the pool, the evolution of the flow, and the evolution of the component in the cold hearth during EBCHM are investigated using a modified multi-physical numerical model. The effects of melting temperature and melting speed on these phenomena were investigated. The purpose is to provide more fundamental knowledge and to further enhance the applications of EBCHM for more titanium alloys. [ABSTRACT FROM AUTHOR]

Rare earths are classified as most important and critical material for US economy and defense by Congress, and a mandate has been set to increase their in-house production, domestic resource utilization and decrease reliance on foreign resources and reserves. They are widely available in earth crust as ore (bastnaesite (La, Ce)FCO3, monazite, (Ce, La, Y, Th)PO4, and xenotime, YPO4), but their so-called economic reserves are sparsely located geographically. They may be produced by various means such as beneficiation (physical, chemical, mechanical, or electrical), reduction (direct or indirect), electrolysis (of aqueous or molten/fused single or mixed salt systems) at high temperature or hydrometallurgy. Out of these, direct reduction, also known as metallothermic reduction (La and Ca reduction), is mostly utilized. Its variant, high temperature electrowinning of fused salts, is also practiced widely. These processes are material- and application-specific. In this study, the author will employ thermodynamics (Ellingham diagrams, free energy of formation, reduction potential, Nernst equation, Pourbaix (Eh-pH) diagrams, E-pO−2 diagrams), kinetics, and energetic of a chemical reaction (chemical metallurgy) to reduce rare earth oxide/salt to rare earth metals (REO/RES – REM). It is shown that materials and energy requirement vary greatly depending on the type of mineral ore, production facility, and beneficiation/mineral processing method selected. The aim is to reduce dependence on coal deposits. It is anticipated this route will be able to produce rare earths with >35% yield and >98% purity which will be described in subsequent studies and patents. [ABSTRACT FROM AUTHOR]

The usage of copper (Cu) ores containing low or no arsenic (As) has reduced, and Cu ores containing high levels of As have emerged as vital mineral resources for Cu extraction and processing. The quality of the Cu ores has decreased from 1.6% to approximately 1.0%. The proportion of As to Cu in 15% of Cu resources currently reaches 1:5. However, during the extraction and processing of Cu ores, As presents significant environmental harm. Hence, safely and effectively removing As is paramount in Cu smelting and processing, holding substantial importance in fostering environmentally sustainable practices within the Cu extraction and processing industry. This article consolidates the resource distribution of As-containing Cu (ACC) ores, comprehensively and systematically evaluates the present advancements in extracting techniques for these minerals, and identifies the challenges inherent in pyrometallurgical and wet processes for treating ACC deposits. Pyrometallurgy is a simple primary roasting technique and has widespread applicability in the treatment of various ACC minerals. Its disadvantages are the emission of exhaust gas and the high treatment costs associated with it. The wet arsenic removal method boasts advantages including minimal air pollution and a high resource recovery rate, significantly aiding in Cu concentrate recovery; its major drawback is the production of As-containing wastewater. The hydrometallurgical removal of As from ACC mines involves extracting As through leaching. Recently, biometallurgy has presented innovative solutions using specialized microorganisms to bioleach or bioabsorb As, but large-scale industrial applications still lack specific practical implementation. This review explores the underlying causes of the challenges encountered in processing ACC minerals. Additionally, it highlights pyrometallurgical roasting coupled with high-temperature filtration as a pivotal advancement in the extraction and processing of ACC ores. [ABSTRACT FROM AUTHOR]

A residue containing TiO2 and PGMs is generated in the hydrometallurgical process used for recycling platinum-group metals (PGMs). In this study, a pyrometallurgical process was considered in which PGMs from the residue generated in the hydrometallurgical process were concentrated in a molten copper phase as a collector metal and TiO2 was separated into the SiO2-CaO-TiO2 slag phase with SiO2 and CaO flux. The dissolution of PGMs must be reduced to minimize the loss of PGMs to the slag. Therefore, the distribution ratios of Pt as representative PGMs between the liquid SiO2-CaO-Al2O3-TiO2 or liquid SiO2-CaO-TiO2 slag and molten copper were measured at 1773K under an oxygen partial pressure of pO2 = 10-10. The experimental results showed that the distribution ratio of Pt increased with TiO2 concentration in the slag, and the distribution ratio of Pt reached a maximum value at a TiO2 concentration of approximately 10 mass%, and decreased with a further increase in TiO2 concentration with the SiO2-CaO-Al2O3-TiO2 slag. However, as TiO2 concentration in the slag increased, the distribution ratio of Pt decreased with the SiO2-CaO-TiO2 slag. Additionally, the experimental results showed that the distribution ratio of Pt between the SiO2- CaO-Al2O3-TiO2 slag and liquid copper increased with the slag basicity B, defined as B = (mass%CaO)/(mass%SiO2) when the TiO2 concentration in the slag was greater than 10 mass%. [ABSTRACT FROM AUTHOR]

Among the technologies used for spent lithium-ion battery recycling, the common approaches include mechanical treatment, pyrometallurgical processing and hydrometallurgical processing. These technologies do not stand alone in a complete recycling process but are combined. The constant changes in battery materials and battery design make it a challenge for the existing recycling processes, and the need to design efficient and robust recycling processes for current and future battery materials has become a critical issue today. Therefore, this paper simplifies the current treatment technologies into three recycling routes, namely, the hot pyrometallurgical route, warm mechanical route and cold mechanical route. By using the same feedstock, the three routes are compared based on the recovery rate of the six elements (Al, Cu, C, Li, Co and Ni). The three different recycling routes represent specific application scenarios, each with their own advantages and disadvantages. In the hot pyrometallurgical route, the recovery of Co is over 98%, and the recovery of Ni is over 99%. In the warm mechanical route, the recovery of Li can reach 63%, and the recovery of graphite is 75%. In the cold mechanical route, the recovery of Cu can reach 75%, and the recovery of Al is 87%. As the chemical compositions of battery materials and various doping elements continue to change today, these three recycling routes could be combined in some way to improve the overall recycling efficiency of batteries. [ABSTRACT FROM AUTHOR]

Copyright of Mining & Metallurgy (10057854) is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The exponentially increasing demand for lithium‐ion batteries and their limited lifetime lead to a significant increase in spent batteries. With the goal to address the sustainability and recyclability to minimize negative effects for the environment, an efficient process is vital to recover valuable materials from spent batteries by recycling. In this regard, deep eutectic solvents (DESs) have attracted huge interest, due to their unique ability to efficiently extract valuable metals from spent batteries, while also being rendered greener and more cost‐effective compared to current pyrometallurgy and/or hydrometallurgy. However, the DES approach also has its own set of challenges and drawbacks, which hinder the widespread use in the industry, including its restricted recyclability, high viscosity, low thermal and chemical stability, complex chemistry, as well as limited scalability. In this perspective, it is claimed that ongoing future research on the recycling of lithium‐ion batteries requires the exploration of alternative processes including modification of current hydrometallurgy processes, if the consistent improvements cannot be achieved in DES system for recycling valuable elements. [ABSTRACT FROM AUTHOR]

Lateritic ores constitute the main source of raw material for extraction of Ni and Co by the Caron process. Consumption of oil in the reduction furnace is one of the key indicators if the metallurgical process is economical. To date it has not been possible to replace the additive fuel oil that is used at commercial scales, therefore, the aim of this study was to partially replace the oil with bituminous coal on a pilot scale by using a mixture of 2 % coal and 1.25 % oil as the reducer additive. Phases of the reduced/leached ores were analyzed by powder X-ray diffraction, while the metallic state of the ore was determined by leaching the reacted samples with a bromine-ethanol solution followed by the atomic absorption spectrometry analysis. Extractions of Ni and Co were confirmed by leaching the reduced ore with ammoniacal-ammonium carbonate solutions. It was observed that the mixture used as a reducer additive can replace the fuel oil since it allows the adequate transformation of the main mineralogical phases of the laterite ore during the reduction process and the average extraction yields of Ni and Co for ~3 and ~8 %, respectively. Although the effect of bituminous coal particle size in the process was not analyzed, the reducing mixture ensured that the Caron process was more efficient.

In metallurgical practice, the material is considered of adequate quality if it meets the customer's expectations. It is necessary to take representative samples and perform quality testing to avoid financial and intangible losses. Sample contamination and matrix and surface quality play a significant role in the accuracy of chemical analyses. The purpose of this paper is to point out the advantages of specific methods of taking samples, such as immersion and spoon sampling of molten metal, and, in the experimental part, to assess the impacts of factors affecting the quality of the sampling. The influence of time of final sampling on determining the true amount of magnesium during a single melt and the influence of duration of mixing of molten cast iron on the accuracy of chemical analysis of the control sample were investigated. It is important that the time between the modification and casting of the liquid cast iron from the casting ladle be as short as possible. This is because the magnesium burns out and thus the chemical analysis of the sample taken is not accurate. Another important factor is ensuring the melt before sampling is homogenized and has the minimum prescribed temperature (1420 °C). Increasing sample collection time will cause changes in its chemical composition. [ABSTRACT FROM AUTHOR]

Metallic materials play a vital role in the economic life of modern societies; hence, research contributions are sought on fresh developments that enhance our understanding of the fundamental aspects of the relationships between processing, properties, and microstructures. Disciplines in the metallurgical field ranging from processing, mechanical behavior, phase transitions, microstructural evolution, and nanostructures, as well as unique metallic properties, inspire general and scholarly interest among the scientific community. Three of the most important elements are included in unit operations in non-ferrous extractive metallurgy: (1) hydrometallurgy (leaching under atmospheric and high-pressure conditions, mixing of a solution with a gas and mechanical parts, neutralization of a solution, precipitation and cementation of metals from a solution aiming at purification, and compound productions during crystallization), (2) pyrometallurgy (roasting, smelting, and refining), and (3) electrometallurgy (aqueous electrolysis and molten salt electrolysis). Advances in our understanding of unit operations in non-ferrous extractive metallurgy are required to develop new research strategies for the treatment of primary and secondary materials and their application in industry. [ABSTRACT FROM AUTHOR]

The significant deployment of lithium-ion batteries (LIBs) within a wide application field covering small consumer electronics, light and heavy means of transport, such as e-bikes, e-scooters, and electric vehicles (EVs), or energy storage stationary systems will inevitably lead to generating notable amounts of spent batteries in the coming years. Considering the environmental perspective, material resource sustainability, and terms of the circular economy, recycling represents a highly prospective strategy for LIB end-of-life (EOL) management. In contrast with traditional, large-scale, implemented recycling methods, such as pyrometallurgy or hydrometallurgy, direct recycling technology constitutes a promising solution for LIB EOL treatment with outstanding environmental benefits, including reduction of energy consumption and emission footprint, and weighty economic viability. This work comprehensively assesses the limitations and challenges of state-of-the-art, implemented direct recycling methods for spent LIB cathode and anode material treatment. The introduced approaches include solid-state sintering, electrochemical relithiation in organic and aqueous electrolytes, and ionothermal, solution, and eutectic relithiation methods. Since most direct recycling techniques are still being developed and implemented primarily on a laboratory scale, this review identifies and discusses potential areas for optimization to facilitate forthcoming large-scale industrial implementation. [ABSTRACT FROM AUTHOR]

Multi-source ferrous metallurgical dust and sludge are significant components of iron-containing solid waste in the iron and steel industry. It is crucial for the sustainable operation of steel enterprises to recycle iron from ferrous metallurgical dust and sludge (FMDS) for use in steel smelting. However, besides Fe, FMDS also contains valuable elements such as Zn, Pb, K, and Na, among others. While these valuable elements hold high recovery value, they impede the direct reuse of FMDS by iron and steel enterprises. This paper introduces the compositional characteristics of multi-source ferrous metallurgical dust and sludge, analyzes the main recycling technologies associated with FMDS at the present stage of development, and discusses the characteristics of different technologies. In view of this, a new idea of the "cooperative treatment of multi-source ferrous metallurgical dust and sludge—full quantitative recovery of valuable elements" is put forward. This new idea integrates a variety of treatment processes to directly recycle FMDS within the steel plant, enhancing the adequacy of dust and sludge recovery and reducing the risk of environmental pollution. This paper provides a reference for achieving the full quantification and utilization of high-value-added FMDS in steel plants. [ABSTRACT FROM AUTHOR]

Adopting EVs has been widely recognized as an efficient way to alleviate future climate change. Nonetheless, the large number of spent LiBs associated with EVs is becoming a huge concern from both environmental and energy perspectives. This review summarizes the three most popular LiB recycling technologies, the current LiB recycling market trend, and global recycling magnates' industrial dynamics regarding this subject. We mainly focus on reviewing hydrometallurgical and direct recycling technologies to discuss the advancement of those recycling technologies and their future commercialization pathway. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries (LIBs) have a wide range of applications from electronic products to electric mobility and space exploration rovers. This results in an increase in the demand for LIBs, driven primarily by the growth in the number of electric vehicles (EVs). This growing demand will eventually lead to large amounts of waste LIBs dumped into landfills which can cause serious environmental problems. To reduce this environmental impact, the need for efficient recycling technology emerges. Furthermore, it has been proven that recycling waste LIBs consume less material and energy than producing new ones from virgin materials. Therefore, this paper aims to review different recycling technologies including hydrometallurgy, pyrometallurgy, direct recycling, and precise separation. The review concludes that hydrometallurgy might be the most efficient method of recycling waste LIBs on an industrial scale. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries (LIBs) are a widely used energy storage technology as they possess high energy density and are characterized by the reversible intercalation/deintercalation of Li ions between electrodes. The rapid development of LIBs has led to increased production efficiency and lower costs for manufacturers, resulting in a growing demand for batteries and their application across various industries, particularly in different types of vehicles. In order to meet the demand for LIBs while minimizing climate-impacting emissions, the reuse, recycling, and repurposing of LIBs is a critical step toward achieving a sustainable battery economy. This paper provides a comprehensive review of lithium-ion battery recycling, covering topics such as current recycling technologies, technological advancements, policy gaps, design strategies, funding for pilot projects, and a comprehensive strategy for battery recycling. Additionally, this paper emphasizes the challenges associated with developing LIB recycling and the opportunities arising from these challenges, such as the potential for innovation and the creation of a more sustainable and circular economy. The environmental implications of LIB recycling are also evaluated with methodologies able to provide a sustainability analysis of the selected technology. This paper aims to enhance the comprehension of these trade-offs and encourage discussion on determining the "best" recycling route when targets are in conflict. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Production Engineering / Revista Brasileira de Engenharia de Produção is the property of Brazilian Journal of Production Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This review focuses on standard Li recycling approaches for LiFePO4 (LFP) and nickel−cobalt−manganese (NCM) cathodes. The study discusses about advances in leaching agents, including organic acid, alkaline solutions, natural organic acid, and electrochemical treatments. Emphasis is placed on the significance of selective Li leaching strategies to optimize the recycling of waste batteries. The review also outlines potential future research directions for enhancing selective recycling, providing valuable insights into the recycling of LFP and NCM batteries. Simultaneously, the article addresses the challenges associated with the transition from conventional lithium-ion batteries to all-solid-state batteries (ASSBs) in the pursuit of sustainable energy storage technologies. It highlights key points, including the challenges in developing ASSBs, the role of employing various material combinations and its preparation techniques, adopting scalable solution-based processes for commercialization, and strategies for sustainable ASSB recycling. The proposition of a fully recyclable ASSB model underscores the commitment to lower recycling costs using safer and simpler methods, positioning nanotechnology as an enabling tool for achieving advancements in materials and cell-level performance.

Leucoxene-quartz concentrate is a large-tonnage by-product of development of the Timan oil-titanium field (oil-saturated sandstones) which is not commercially used at present. High content of titanium compounds (to 50 % by weight) and lack of industrial, cost-effective, and safe technologies for its processing determine a high relevance of the work. Conventional processing technologies allow increasing the concentration of TiO2, but they are only a preparation for complex and hazardous selective chlorination. The process of pyrometallurgical conversion of leucoxene-quartz concentrate into aluminium and magnesium titanates was investigated. It was ascertained that the temperature of solid-phase reaction in Al2O3-TiO2-SiO2 system necessary for the synthesis of aluminium titanate (Al2TiO5) is 1,558 °С, and for MgO-TiO2-SiO2 system – 1,372 °С. Scaling up the process made it possible to synthesize a significant number of samples of titanate-containing products, the phase composition of which was studied by X-ray phase analysis. Two main phases were identified in the products: 30 % aluminium/magnesium titanate and 40 % silicon dioxide. In products of pyrometallurgical processing in the presence of aluminium, phases of pseudobrookite (3.5 %) and titanite (0.5 %) were also found. It was ascertained that in magnesium-containing system the formation of three magnesium titanates is possible: MgTiO3 – 25, Mg2TiO4 – 35, MgTi2O5 – 40 %. Experiments on sulphuric acid leaching of samples demonstrated a higher degree of titanium compounds extraction during sulphuric acid processing. An integrated conceptual scheme for processing leucoxene-quartz concentrate to produce a wide range of potential products (coagulants, catalysts, materials for ceramic industry) was proposed.

Lithium-ion batteries (LIBs) with high power density are commonly used in electric vehicles and portable electronic devices. Their applications have been soaring in recent years resulting in an increasing number of used LIBs. Spent LIBs containing heavy metals and toxic hazardous are becoming a severe threat to the environment and human health which must be addressed properly. Recycling is an option for end-of-life LIBs, which not only prevents the pollution of toxic components but also saves natural sources. This paper introduces battery structures and gives an overview of the current state of waste LIBs and their recycling status. Moreover, recent advancements in hydrometallurgy, pyrometallurgy, and direct recycling at both research and industrial levels are deeply analyzed. This document can serve as a useful reference resource for researchers or engineers, who might profit from applying the concept to the examples summarized in the comprehensive review paper.

In recent years, with the gradual expansion of the global market for new energy vehicles, the supply and demand of lithium-ion batteries (LIBs) as a source of energy have been increasing, which directly promotes the significant increase in the number of used LIBs. Among them, ternary LIBs have been widely used because of their high specific capacity and excellent multiplying performance, which has aroused people’s concerns about their proper disposal. On the one hand, ternary LIBs contain rich nonferrous metals, such as lithium, nickel, cobalt, and manganese, with high recovery values. On the other hand, spent ternary LIBs contain a large number of toxic electrolytes and heavy metals, which will cause environmental pollution and damage human health if not handled properly. Therefore, research on the recycling and regeneration of spent ternary LIBs has been receiving considerable attention. Given the principles of low energy consumption, “green” recovery, and high recovery rate, this study briefly introduces the main failure causes of cathode materials for ternary LIBs and discusses the application scope and the advantages and disadvantages of traditional pyrometallurgy (such as chemical reduction and salinization roasting) and hydrometallurgical leaching processes (such as acid, alkali, and biological leaching). This review creatively summarizes the research progress on regeneration after hydrometallurgical leaching (such as coprecipitation and sol–gel methods) and direct regeneration (such as high-temperature solid-phase method, solvothermal treatment, and molten salt method) of spent ternary LIBs in recent years and analyzes the advantages and disadvantages of various regeneration technologies. Notably, compared with traditional pyrometallurgy and hydrometallurgy, the process of regeneration after hydrometallurgical leaching and direct regeneration considerably reduces the complexity of the process flow, maximizes the comprehensive utilization rate of nonferrous metals, and realizes the closed-loop recovery route of spent LIB cathode. Based on this, the innovative strategy of upgrading the cathode material of regenerated ternary LIBs through ion doping and surface coating modification, which effectively improved the poor thermal stability, short cycling, and low rate performance of ternary LIBs caused by high nickel content, was particularly discussed. Finally, from the perspective of recycling methods, multiple modification strategies, and mechanism research, the future development of recycling technology for spent ternary LIBs is proposed. This study aims to provide some references and suggestions for the improvement of the spent LIB recycling system and establish a closed-cycle recycling system for the production and recycling of spent LIBs.

With the rapid development of the new energy vehicle industry, the number of power battery decommissioning is increasing year by year. The recycling of power batteries is of great significance for protecting the ecological environment, improving the efficiency of resource utilization, and ensuring the sustainable and healthy development of the new energy automobile industry. In this study, the chemical compositions of power batteries were introduced, the technical path and development status of the echelon utilization of decommissioned power batteries were discussed, and the specific steps and challenges of regenerative utilization of decommissioned power batteries were described in detail from two aspects of pyrometallurgy and hydrometallurgy. Combined with the relevant research results, the main methods of the direct regeneration of positive electrode materials were analyzed. Finally, the main development direction and related suggestions for the resource utilization of decommissioned power batteries were put forward. [ABSTRACT FROM AUTHOR]

The expected large growth in electric mobility presents challenges, such as requiring a very large amount of critical raw materials like nickel, cobalt, and lithium. Due to this expected growth significant amounts of production scrap from cell and battery manufacturing will be generated. Over the next decade, increasingly larger amounts of Li-ion batteries from electric vehicles will also reach their end-of-life. Hence, in order to close the loop, the development and industrialization of sustainable battery recycling flowsheets are key so that both production scrap and end-of-life batteries can be recycled back to their 'battery grade' building blocks. Battery recycling flowsheets are typically categorized into two categories: (1) 'Pyro-Hydro', a combination of battery smelting in a pyrometallurgical process, followed by the further refining of the alloy via hydrometallurgy; and (2) '(Thermo)mechanical-Hydro', a combination of (thermo)mechanical pretreatment and further hydrometallurgical refining of the resulting black mass. In this paper, a carbon footprint analysis is presented comparing these two battery recycling approaches: 'Pyro-Hydro' and 'Thermomechanical-Hydro', taking into account the impact of the latest evolutions in process technology and efficiency. To facilitate this comparison, a prospective LCA was carried out for the respective flowsheets. The quantitative analysis shows that 'Pyro-Hydro' leads to the lowest overall carbon footprint but also that both 'Pyro-Hydro' and 'Thermomechanical-Hydro' flowsheets have their challenges and opportunities for decarbonization. The inclusion of the fate of side streams such as graphite and electrolyte in the analysis is shown to be critically important in order to gain an objective and complete view. [ABSTRACT FROM AUTHOR]

This report analyzes various methods of disposal and processing of exhaust from complex chemical current sources, subdivided into pyrometallurgical, hydrometallurgical, and combined. The complex technology for processing lithium-cobalt current sources (LCCS), developed at the National Research Center Kurchatov Institute, is described, including the stages of discharge, opening in an inert atmosphere, crushing, grinding (with mechanical activation), and leaching with extraction. The data from additional studies on the alkaline leaching process of the LCCS cathode are presented. In this case, the degree of aluminum extraction from the LCCS cathode reached 94.2%. Data on a comprehensive study of the distribution of metal components in fractions after grinding and milling in blade and ball mills were analyzed. The results showed that Co, Li compounds, and graphite are contained in powders of size 50–1000 pm, and fractions of size 1000–2500 pm contain Cu, Al compounds, and polymer particles. A fractional (staged) technology is proposed for separating valuable metal components from LCCS with water separation and leaching. The results of leaching mechanically activated powders with inorganic acids are presented. A comparative analysis of the results obtained with data from international authors on the efficiency of LCCS leaching was performed, and a mathematical description of the process kinetics was proposed. A modernized block diagram of combined mechanical processes with leaching and extraction processes was developed. [ABSTRACT FROM AUTHOR]

Heterogeneous slag viscosity measurements have a wide variety of parameters, such as particle size, shape, solid volume fraction, and shear rate, which affect the final measured viscosity. Often, some of these parameters are neglected or predicted via models, since it is experimentally difficult to determine them during high-temperature slag viscosity measurements. In this work, a viscosity apparatus was used, which allows quenching of the sample after measurement. This way, all relevant parameters could be experimentally determined. The viscosities of three datasets were studied with various spinel sizes: small (13 μ m), medium (34 μ m), and large particles (76 μ m). Within each dataset, the composition of the liquid slag matrix was kept constant to uniquely measure the effect of solids. Shear thinning, i.e., a decreasing viscosity with increasing shear rate, was observed for all samples, even at a low vol. % of 1.8. Moreover, stronger shear thinning was observed at a higher vol. % and for smaller spinel particles. On the basis of these results, the phenomenon of shear thinning was discussed and mainly attributed to the particle–particle orientation in the suspension. The obtained viscosity values were used to optimize a Krieger–Dougherty equation, which describes the viscosity increase caused by the presence of a certain vol. % of spinel particles, with a certain size and at a specific shear rate. [ABSTRACT FROM AUTHOR]

The literature indicates that utilizing pyrometallurgical methods for processing spent LiCoO2 (LCO) batteries can lead to cobalt recovery in the forms of Co3O4, CoO, and Co, while lithium can be retrieved as Li2O or Li2CO3. However, the technology's high energy consumption has also been noted as a challenge in this recovery process. Recently, an innovative and sustainable approach using microwave (MW) radiation has been proposed as an alternative to traditional pyrometallurgical methods for treating used lithium-ion batteries (LiBs). This method aims to address the shortcomings of the conventional approach. In this study, the treatment of the black mass (BM) from spent LCO batteries is explored for the first time using MW–materials interaction under an air atmosphere. The research reveals that the process can trigger carbothermic reactions. However, MW makes the BM so reactive that it causes rapid heating of the sample in a few minutes, also posing a fire risk. This paper presents and discusses the benefits and potential hazards associated with this novel technology for the recovery of spent LCO batteries and gives information about real samples of BM. The work opens the possibility of using a microwave for raw material recovery in spent LIBs, allowing to obtain rapid and more efficient reactions. [ABSTRACT FROM AUTHOR]

The management and recycling of waste which contains critical metals has become a high priority. Improper management of this waste leads to adverse effects for both the environment and human health. An equally important driver is the rapidly growing demand to recycle critical metals from waste to reduce environmental impacts and transition to zero-carbon technologies. The aim of the paper is to provide knowledge about waste containing lithium and zinc and the pros and cons of different treatment and recovery methods to policymakers, industrialists, researchers, and students. To that end, we identify sources of lithium- and zinc-based waste and compare and discuss the benefits and challenges of treatment and recovery procedures including pyrometallurgy, bioleaching and acid-leaching. We also explore the socio-economic aspects of lithium and zinc metals and environmental impacts of wastes containing these metals. Finally, we provide a summary of literature containing life-cycle analysis (LCA) studies for the recovery of lithium and zinc from waste sources. [ABSTRACT FROM AUTHOR]