Ni‐Co 2025, 6th International Symposium on Nickel and Cobalt

To meet the stringent specifications required for LME Grade A cobaltCobalt (Co) cathode productionProductions, cobaltCobalt refineries must reduce impurities such as cadmiumCadmium (Cd) and copperCopper (Cu) to trace levels (< 0.1 mg/L) in the electrolyte. The primary challenge is to selectively remove these impurities without affecting the cobalt electrolyteCobalt electrolyte or causing any loss of valuable cobaltCobalt content. SuperLig®SuperLig® molecular recognition technologyTMMolecular recognition technologyTM (MRTTM) provides an innovative solution for impurity removalImpurity removal by selectively targeting specific metalMetals ions while leaving non-target ions unaffected. This study examines the use of MRTTM to selectively remove Cu and Cd from Co electrolytes, where initial concentrations of ~ 410 ppm Cu and ~ 30 ppm Cd were reduced to below detection limits in the Co electrolyte. Two distinct MRTTM systems were utilized: one with SuperLig®SuperLig® 132 for Cu removal and the other with SuperLig®SuperLig® 177 for Cd removal. These findings highlight the effectiveness of MRTTM in achieving the stringent impurity thresholds required to produce LME Grade A cobaltCobalt cathodes without compromising electrolyte characteristics or productionProductions.

CobaltCobalt is critical to the renewable energy sector due to its use as the raw material for rechargeable batteriesBattery. The rapidly growing batteryBattery industry consumes more than 80% of the worlds Co, which is creating concern about future supplySupply. There are three main primary cobaltCobalt deposit types: sediment-hosted Cu deposits, Ni sulfide deposits, and Ni lateriteLaterites deposits, where cobaltCobalt is recovered as a by-product along with Cu and Ni. In the future, Co may be sourced from polymetallic ocean nodules. Co recoveries from conventional metallurgical processes have typically been low. It is therefore an opportune time to consider how unconventional resources such as metallurgical waste can be reprocessed to help meet the demandDemand for Co. In this paper, we review the characteristics and process options for Co in Caron process residue, pyritePyrite tailingsTailings, and metallurgical slagsSlag. While these materials contain Co, cost-effective recovery of Co from these streams remains a challenge. For example, the Co concentration is typically low (< 0.5 wt.%), and the Co is largely unliberated, requiring a chemical reaction to facilitate effective extractionExtraction. In this article, we will review these opportunities considering the previous literature as the basis of a discussion to develop future pathways to reprocess these metallurgical process wastes.

AtHydrothermal iron removal Rustenburg Base MetalsMetals Refinery, the primary nickelNickel leach liquor is processed through a neutralisation–hydrothermal autoclaveAutoclave treatment at 140–150 °C using caustic soda to remove solubilised iron as a hematiteHematite/natrojarositeNatrojarosite residue. A dynamic model of the process was developed to evaluate a pH control strategy for this process with the objective of minimising co-precipitationPrecipitation of nickelNickel and copperCopper. A transient reactive mass-balance model was developed to describe measured data by data fitting and a simplified version of the mass balance was used for control algorithm modellingAutoclave modelling. The simplified version is less accurate and only provides pH as an output, whereas the transient mass balance can output pH, aqueous flows of base metalsMetals, and flows of phases formed in the residue. The fitted dispersion parameters in the mass-balance model suggest that dispersion of caustic soda within the autoclaveAutoclave is orders of magnitude slower than that of the aqueous feed, which is a consequence of the relative flows, compounded by a surface dosing configuration. Slow dispersion of caustic soda amplifies its excess requirement, hence promoting copperCopper and nickelNickel hydroxide formation in the residue. Elevated autoclaveAutoclave temperature was found to depress iron concentration in the autoclaveAutoclave aqueous product stream. Simulation of a dependent-gains controller illustrates that adequate control of the autoclaveAutoclave discharge pH is possible by automatic adjustment of the caustic:feed flow ratio; however, the response lag associated with the manipulated variable is of the order of 30 min and warrants an advanced process control solution.

As the global demandDemand for nickelNickel intensifies across industries such as stainless steel, corrosionCorrosion-resistant alloys, clean energy, and advanced infrastructure, high-grade nickelNickel ore reserves are being progressively depleted. This review provides a detailed analysis of metallurgical processes for nickelNickel extractionExtraction from sulfide ore resources, with a focus on recent advancements and potential trends in nickelNickel metallurgy. The primary methods, pyrometallurgical and hydrometallurgical, are examined, covering smeltingSmelting, leachingLeaching, and purification processes. Their respective advantages and limitations are critically compared, offering insights for the developmentDevelopment of innovative smeltingSmelting technologiesTechnology. Special emphasis is placed on biological metallurgy, which is highly selective for nickel recoveryNickel recovery and considered the most promising method for future research. This paper highlights advancements in extractionExtraction technologiesTechnology, emphasizing environmentally friendly methods and integrating carbon capture techniques. These innovations aim to optimize nickel recoveryNickel recovery, reduce environmentalEnvironmentalEnvironmental impacts, and meet the growing global demandDemand driven by the transition to clean energy.

Co and Ni niobateNiobate compounds have attracted significant research interest for their suitability in lithiumLithium-ion batteryBattery applications. Complicated and costly synthesis methods hinder the successful commercialization of many niobateNiobate material applications. Therefore, simpler and more economical synthesis methods are needed for large-scale applications. This study investigates the precipitationPrecipitation of Ni and Co niobateNiobate precursors from aqueous solution, using different sources of niobium (ammonium niobateNiobate oxalate and niobium pentoxide) and other metalsMetals (inorganic salts) at varying pH. These precursors are characterized, and the relationship between their properties and the characteristics of the products after calcination is presented, as the crystallinity of the niobateNiobate depends on the temperature and calcination time. Characterization techniques for chemical assay (XRF), phase identification (XRD, Raman spectroscopy), and size and morphology (TEM) are employed for the precursors and niobatesNiobate, while ICP-OES and TOC techniques are used for the characterization of the solutions.

Eurasian Resources Group’s (ERG) Metalkol operation in the Democratic Republic of the Congo (DRC) produces copperCopper cathode and cobaltCobalt hydroxide from the retreatment of historic copperCopper-cobaltCobalt tailingsTailings left by previous mining operators in the Kingamyambo tailingsTailings Dam and Musonoi River System. The dynamic behaviour of this river system has caused distinct areas with high variability in terms of the particle size distribution, and clay and impurity content that need to be managed carefully to ensure a controlled feed to processingProcessing. Higher levels of cadmiumCadmium and zinc in this material are of concern due to pressure from end users to reduce these impurities in the Co(OH)2 product. Selective precipitationPrecipitation with an organo dithiophosphate, as used in the phosphoric acidPhosphoric acid industry for heavy metalsMetals removal, has been investigated for the treatment of the cobaltCobalt (Co) solution. Bench scale experiments, continuous pilot plant, and plant trials have shown that cadmium removalCadmium removal efficiencies of > 98% can be achieved. Key technical and economic considerations relate to the solids content of the dosing point and the base metalMetals content of the streams, which greatly affect the dosing requirements to achieve the cadmium removalCadmium removal target. The difference in performance between reagents was established, and the choice between reagents would depend on the specific priorities and requirements of the process, such as the desired Cd concentration in the downstream product and the acceptable level of Co loss.

The present study explores the use of gas-filled micro- and nanobubblesNanobubbles (MBs and NBs) in the hydrometallurgical extractionExtraction via leachingLeaching of critical and strategic metalsCritical and strategic metals from a zinc-plant industrial residue. These gas-filled bubbles have sizes typically ranging from 1 to 100 μm and 1 to 1000 nm, respectively. Compared to ordinary macrobubbles, MBs and NBs are more stable with unique physicochemical properties such as low floating rate, large specific area, high charge density and surface tension, tremendous mass transfer efficiency, and self-pressurized dissolutionDissolution. These properties are dependent upon the type and nature of the gas (e.g., oxygen (O2)) filling these bubbles, which often possess the ability to produce reactive oxygen species which provide excellent oxidative capacity. In this work, O2 gas-filled MBs, and NBs were generated in 500 mL of 1 M sulfuric acidSulphuric acid (H2SO4) for the entirety of the experiment. This O2 NB charged solution was used in a leachingLeaching experiment of critical and strategic metalsCritical and strategic metals from the zinc-plant industrial residue performed at 80 °C for 1.5 h. LeachingLeaching with H2SO4 without NBs was used for comparison. The results from this work hold significant value, especially in the realm of improving the performance of hydrometallurgical processesHydrometallurgical processes in an eco-friendly and cost-effective manner.

For the economic extractionExtraction of important precious metalsMetals—nickelNickel, zinc, platinumPlatinum, gold, cobaltCobalt, uranium, and rare earths, there are various process engineering routes to extract these important metalsMetals from the ore. One established and economical process is the hydrometallic process route with integrated solvent extraction (SX)Solvent Extraction (SX), which separates these metalsMetals after leachingLeaching in a solution. All pilot and commercial SXSolvent Extraction (SX) systems experience the formation of crud—a solid-stabilized emulsion that accumulates at the aqueous/organic interface in the settlers of the solvent extraction stages. It is caused by a variety of substances entering the SX circuitSX circuit, such as windblown dust, entrained solids from leachingLeaching, impurities in the plant solutions. While a thin layer of at the aqueous/organic interface can promote coalescence of fine droplets, excess crud interferes with phase separation resulting in greatly reduced extractionExtraction efficiency of the settling tanks. Crud prevents mass transfer from proceeding efficiently at the phase interface. This crud can be solved by our technologyTechnology of three-phase decanter centrifugesDecanter centrifuges. By centrifugal force we are able to separate this crud layer continuously into its individual components. How the three-phase decanter centrifugeDecanter centrifuges technologyTechnology works. The design and operation of the three-phase centrifuge is similar to that of a decanter (two-phase separation). The solids settle on the inner wall of the bowl under the action of centrifugal force. The screw takes care of the solids transport for centrifuged solids with a differential speed to the decanter bowl. The decisive difference to the decanter lies in the separate expulsion of the two liquid phases. In the 3-phase decanter centrifugeDecanter centrifuges, the light liquid is discharged under pressure with subsequent DControl monitoring. The heavy liquid flows out without pressure. The DControl allows stepless adjustment of the pond depth during operation and leads to fast and precise adaptation to changing feed conditions without interrupting operation. This DControl system is presented in detail in this paper and presentation.

NickelNickel (Ni) and cobaltCobalt (Co) are essential elements for the productionProductions of lithiumLithium-ion batteriesBattery (LIBsLithium Ion Batteries (LIB)). With the increasing demandDemand for these batteriesBattery, the need for high-purity Ni and Co has surged. This paper presents a robust process for the selective recovery of Ni and Co from a chloride leachingLeaching solution containing Ni (0.29%), Co (0.33%), Cu (0.66%), and other metalMetals impurities. CopperCopper was effectively removed by selective precipitationPrecipitation at 94% through pH adjustment, ensuring minimal interference in the subsequent extractionExtraction steps. Impurities such as Fe, Zn, Ca, and Pb were extracted using D2EPHA, while minimizing the co-extractionExtraction of Ni and Co. The optimal extractionExtraction conditions were identified at a 1/2 organic-to-aqueous ratio, with extractionExtraction efficiencies of 75.35% for Fe, 78.74% for Zn, 98.54% for Ca, and 30.8% for Pb. Co was efficiently extracted using CYANEX 272 at 68.54% in a single stage with a co-extractionExtraction of 18.7 ppm for Mg. For Ni, a high selectivity was achieved at 96.26% using 15% v/v of VERSATIC 10 in 85% v/v of kerosene with co-extractionExtraction of 19 ppm for Mg. Subsequent stripping with 2 M sulfuric acidAcid resulted in a Co recovery of 64.55% and a Ni recovery of 51.59% at a 1/4 organic-to-aqueous ratio for both. These results, achieved in a single-stageSolvent Extraction (SX), can be further optimized by incorporating additional extractionExtraction and stripping stages and conducting tests at higher temperatures.

The growing demandDemand for electric vehiclesElectric Vehicles (EVs) has significantly increased the need for Ni and Co, essential components in batteriesBattery. A novel hydrometallurgical processHydrometallurgical processes has been developed to selectively recover Ni and Co from Cu–Ni matteMatte containing approximately 71.3% Cu, 6.1% Ni, 0.2% Co, and minor impurities like Fe, primarily as sulfides. Selective atmospheric leachingLeaching with HCl and H2O2 was employed to extract Ni and Co, leaving most of Cu as a leach residue that can be a potential feedstock for Cu refinersFeedstock for Cu refiners. Residual Cu was removed by cementation, followed by precipitationPrecipitation to eliminate Fe and other impurities, achieving over 99% separation of Cu and Fe with minimal Ni loss (approximately 2%). In the final step, carbonation with Na2CO3 precipitated Ni as NiCO3NiCO3 under optimal conditions (pH 7.5, 60 °C), meeting battery materialBattery materials specifications.

Common processes to extract metalsMetals from refractoryRefractory ores or laterite oresLaterite ore rely on high-pressure applications in autoclavesAutoclave, e.g., high-pressure acidAcid leachingLeaching (HPAL) to extract nickelNickel and cobaltCobalt or pressure oxidation (POXPressure Oxidation (POX)) in cases of copperCopper, gold, zinc, etc. In both processes, ore is mined, crushed and a slurry is created by addition of water or acidAcid. This slurry is treated at elevated temperature and pressure (e.g., T > 200°C, P > 30 bar) in an autoclaveAutoclave. To return the slurry to atmospheric conditions, an array of flash vesselsFlash vessel is used. Via decantation and selective precipitationPrecipitation the desired metalMetals, metal oxideMetal oxides or metalMetals salt can be accumulated and purified. As each step requires a specific corrosion protectionCorrosion protection liningLining, different liningLining setups were used in autoclavesAutoclave, flash vesselsFlash vessel, etc. Especially for high-pressure applications in autoclavesAutoclave and flash vesselsFlash vessel combined liningsCombined linings of membranes, bricks and inserts of poly-(tetra-fluoro-ethylene) (PTFE), titanium or Inconel are used. Looking at various ore processing plantsProcessing plant around the world, different kinds of membranes are combined with different types of brick liningsLining aiming for a long-lasting and efficient corrosion protectionCorrosion protection. Membranes protect the steel vessels itself against chemical attack. Widely used in pressure vessels are lead membranes, glass fiber-reinforced coatings or rubber liningsLining. Also explosion plated titanium or welded on Inconel is partially used. The main task of the additional brick liningLining is to protect the membrane against abrasion or mechanical impact. AcidAcid resistant ceramic bricks, carbon bricks, graphene bricks or different specialties are widely used. Depending on the local load (e.g., liquid phase, gas phase, transition zone), different types of mortars are used to install the brick liningLining. During the presentation, we will look back on decades of experience with different liningLining combinations and show pros and cons in application, operation, maintenance, repair, and relining.

BatteryBattery-grade metal sulfatesMetal sulfate, which are key raw materials for lithiumLithium-ion batteryBattery manufacturing, are continually growing in demandDemand due to the expansionExpansion of the electric vehicleElectric Vehicles (EVs) market. One important pathway to produce these batteryBattery-grade metal sulfatesMetal sulfate is via a metalMetals dissolutionDissolution process, which involves the dissolutionDissolution of nearly pure metalsMetals (e.g., Ni, Co) and the subsequent leachate purification. This is a proven and viable approach that offers producers an accelerated route to enter the batteryBattery market. This paper discusses the various merits of the metalMetals dissolutionDissolution pathway and explores the strategic uses of the metalMetals dissolutionDissolution plant across the value chain, including precursor cathode active material (pCAMPrecursor Cathode Active Material (PCAM)) producers, batteryBattery recyclers aiming to produce pCAM, and metalMetals producers. Furthermore, the benefits of integrating a metalMetals dissolutionDissolution facility with existing operations are highlighted. Through addressing design considerations and integrating operations, the competitiveness of the metalMetals dissolutionDissolution plant can be maximized in the rapidly evolving batteryBattery market.

The resin in moist mixResin in moist mix process was investigated for its potential use in nickel lateriteNickel laterite extractionExtraction, focusing on the adsorption performance of iminodiacetic IX resinsIminodiacetic IX resin for nickelNickel and cobaltCobalt. Using a factorial experimental design, the study examined the effects of four process variablesProcess variables, i.e., resin quantity, water content, amount of acidAcid, and leachingLeaching-sorption time. Statistical analysis of variance was used to establish significant relationships between these factors, and metalMetals loading. The obtained results showed that nickelNickel adsorption was primarily influenced by longer times, higher acid consumptionAcid consumption, and lower resin quantities, while cobaltCobalt adsorption improved with reduced acidAcid dosage and shorter leachingLeaching-sorption times.

The complex mineralogyMineralogy of nickel lateriteNickel laterite ores poses challenges for existing atmospheric extractionExtraction methods, leading to a preference for high-pressure acidAcid leachingLeaching. Notwithstanding, decreasing nickel lateriteNickel laterite grades render existing pressure acidAcid leachingLeaching process less economical. In this study, a Milestone SynthWave reactorMilestone SynthWave reactor was utilized to assess its impact on cobaltCobalt and nickelNickel extractionExtraction at different leachingLeaching conditions. An increase in acidAcid (H2SO4) concentration from 0.19 M to 0.96 M led to ~ 64% and 99% Ni and Co extractionExtraction, respectively, at 40 min of leachingLeaching. At lower acidAcid concentrations (0.19 M), extending the leach time was beneficial, while at higher acidAcid concentration (0.96 M), little or no additional impact was seen. Citric acid–AcidH2SO4 leach rates were higher for Co and selective toward Mn than Ni and Fe. EDTA–Ethylenediaminetetraacetic Acid (EDTA)H2SO4 leachingLeaching was favorable toward Ni than citric acid–AcidH2SO4 leachingLeaching. NaCl–H2SO4 was preferential toward Mg dissolutionDissolution than nickelNickel and cobaltCobalt. Overall, the leachingLeaching behavior of nickelNickel and cobaltCobalt in the goethitic ore was significantly influenced by elevated temperatures and pressures.

In 2005, Niihama NickelNickel Refinery (NNRNiihama Nickel Refinery (NNR)) of Sumitomo MetalMetals Mining Co., Ltd. started to treat nickelNickel-cobaltCobalt mixed sulfideMixed sulfide (MS) through Coral Bay NickelNickel Corporation, which was established in the Republic of the Philippines. The increase of MS productionProductions has significantly expanded NNRNiihama Nickel Refinery (NNR)’s plant capacity of electrolytic nickelNickel. In processingProcessing nickel matteNickel matte and MS, there were concerns about the deterioration of the nickel recoveryNickel recovery ratio due to differences in their reactivity in the chlorine leach circuit. In response to this, NNRNiihama Nickel Refinery (NNR) improved productionProductions efficiency through optimizing the leachingLeaching method and implementing equipment modifications, and accomplished an increase in the productionProductions capacity of electrolytic nickelNickel to 65,000 tpa.

The demandDemand for nickelNickel and cobaltCobalt is consistently increasing with a rapid advancement of lithiumLithium-ion batteriesBattery (LIBsLithium Ion Batteries (LIB)) for clean technologiesTechnology and energy storage. NiVolt has developed a sustainable patent pending hydrometallurgical technologyTechnology through batch and continuous pilot plant operations to extract and convert the nickelNickel and cobaltCobalt contained in sulphide concentrates of the Dumont NickelNickel Project into mixed hydroxide precipitate (MHP)Mixed Hydroxide Precipitate (MHP) for lithiumLithium-ion battery materialsBattery materials supplySupply chain in North AmericaNorth America. The process can extract up to 99% nickelNickel and cobaltCobalt under the optimal pressure oxidationPressure Oxidation (POX) conditions with a minimum amount of iron contained in the pregnant leach solution (PLS). The leach slurry undergoes pH adjustment to remove impurities, including aluminum and iron. The purified PLS is used to produce MHPMixed Hydroxide Precipitate (MHP). This process produces a relatively clean, high-grade MHP, which can be used as a feed for producing precursor cathode active materialsPrecursor Cathode Active Material (PCAM) (pCAM) of LIBsLithium Ion Batteries (LIB). This paper will describe the potential unit operations with process chemistry and batch test results.

Numerous producers of Class I metallic nickelNickel (Ni), Ni concentrates, as well as other intermediate products such as mixed hydroxide precipitateMixed Hydroxide Precipitate (MHP) and mixed sulfideMixed sulfide precipitate are considering converting their output to an upgraded product that is readily usable within the electric vehicleElectric Vehicles (EVs) (EVElectric Vehicles (EVs)) battery materialBattery materials supplySupply chain. Preceding EVElectric Vehicles (EVs) batteryBattery manufacturers in the EVElectric Vehicles (EVs) batteryBattery supplySupply chain are precursor cathode active materialPrecursor Cathode Active Material (PCAM) manufacturers who directly require Ni units. To incorporate these Ni units, there are several intermediate Ni product options, and it is important to determine which of these options represents the best value from technical, commercial, environmentalEnvironmental, and strategic perspectives. Following the selection of the best value Ni intermediate option(s), then the hydrometallurgical processHydrometallurgical processes options can be evaluated. This paper reviews a broad range of hydrometallurgical processHydrometallurgical processes options used to produce Ni sulfateSulfate and other Ni intermediates, including high pressure acid leachHigh pressure acid leach processingProcessing of lateritic Ni ores; pressure oxidative leachingLeaching of Ni sulfide concentrates; acidAcid dissolutionDissolution of Ni powder produced hydrometallurgically, or carbonyl Ni powder; and secondary recovery of Ni during electrorefining of copperCopper anodes obtained from smeltingSmelting of copperCopper scraps with high Ni content. A technical and commercial assessment of different process options to produce Ni values in a sustainable fashion for EVElectric Vehicles (EVs) batteryBattery supplySupply chain is provided and the comparative technical considerations, and sustainabilitySustainability and economic viability of each option are discussed.

The Atlas Materials Process for nickelNickel, magnesiumMagnesium, and cobalt recoveryCobalt recovery from saproliteSaprolite ores began developmentDevelopment in 2021 at SGS Lakefield, originally conceived as a study investigating the amenability of hydrochloric acidHydrochloric acid treatment for a variety of magnesiumMagnesium/silica enriched feedstocks (including asbestos tailingsTailings, olivineOlivine sand, and saproliteSaprolite). The investigation eventually grew to include testingTesting designed to generate separate magnesiumMagnesium, nickelNickel/cobaltCobalt, and Supplemental Cementitious MaterialSupplemental Cementitious Material (SCM) (SCM, to replace fly ash in the productionProductions of cement) products, in a process with nominally zero solid wastes. This paper will provide an overview of the testingTesting that was conducted at SGS Lakefield, from bench scale testingTesting to the more than twelve pilot plant campaigns operated within a span of three years. Specific attention will be given to the improvements to the process made over time as the flowsheetFlowsheet evolved based on the findings of the investigation. This includes the application of non-traditional alkaline reagents for impurity removalImpurity removal, confirmation of the process using a variety of potential feedstocks, and evaluation of different downstream process configurations and reagents to provide flexibility within the unit operations and final products.

Solvent extraction (SXSolvent Extraction (SX)) is a crucial process in the mining industry, essential for the separation, recovery, and purification of critical metalsCritical metals such as cobaltCobalt, nickelNickel, rare earth elements, and others. Due to the complexity of feed solutions, flowsheetsFlowsheet, and stringent product purity requirements, the successful design and operation of SXSolvent Extraction (SX) plants depend on several parameters. Digital toolsDigital tools that offer circuit modelingCircuit modeling solutions for the mining industry can significantly improve the design and operation of both existing and new SXSolvent Extraction (SX) plants. Circuit modelingCircuit modeling enables mine operators and engineering firms to optimize plant design, reduce operational risks and costs, and ensure efficient and effective operations. SYENSQO’s newly expanded digital toolDigital tools, MINCHEM + TMMINCHEM+TM, is an advanced solution specifically developed to enhance SXSolvent Extraction (SX) processes in the mining industry. MINCHEM + TMMINCHEM+TM utilizes lab-generated equilibrium data to simulate fully integrated SX circuitsSX circuit, taking into account factors such as reagent types, concentrations, circuit configurations, and pH requirements. MINCHEM + TMMINCHEM+TM features a user-friendly interface and rapid computation capabilities, allowing for precise modeling of complex SX circuitsSX circuit. It supports the optimizationOptimization of reagent usage and plant parameters, facilitating quicker trials and accurate stage efficiency calculations. This tool is part of SYENSQO’s broader suite of digital solutions designed to address the challenges of complex separations, high product purity requirements, and complex SXSolvent Extraction (SX) flowsheetsFlowsheet. MINCHEM + TMMINCHEM+TM contributes to the advancement of the mining industry's SXSolvent Extraction (SX) capabilities, ensuring more efficient, effective and sustainable operations.

The Baptiste deposit is a large tonnage, low-grade, near surface, nickelNickel deposit located in central British Columbia, Canada, that is currently being developed by FPX NickelNickel Corp. Baptiste is a serpentinized ultramaficUltramafic deposit that, critically, was near barren in sulphurSulphur during mineral alteration resulting in the formation of awaruiteAwaruite, a metallic nickelNickel-iron alloy (Ni3Fe), as the dominant nickelNickel mineral. Part 1 of this paper summarizes the mineral processingProcessing developmentsDevelopment that result in the productionProductions of an awaruiteAwaruite mineral concentrate grading 60% Ni, primarily through low-intensity wet magnetic separation followed by froth flotationFlotation. This awaruiteAwaruite mineral concentrate is of sufficient grade and purity to be used directly in stainless steel productionProductions as a low carbonLow carbon intensity replacement for ferronickelFerronickel or, in select instances, class 1 nickelNickel. Alternatively, the awaruiteAwaruite mineral concentrate can be refined to produce a high-purity nickelNickel product to meet the growing demandDemand from the batteryBattery electric vehicleElectric Vehicles (EVs) supplySupply chain. Part 2 of this paper summarizes the developmentDevelopment of a hydrometallurgyHydrometallurgy flowsheetFlowsheet to refine the Baptiste awaruiteAwaruite mineral concentrate into high-purity nickel sulphateNickel sulphate. The resultant flowsheetFlowsheet consists of a counter-current, sulphuric acidSulphuric acid leach using medium-temperature pressure oxidationPressure Oxidation (POX) and atmospheric oxidation leach stages, producing a neutralized, iron-free, high-nickelNickel grade pregnant leach solution suitable for downstream purification using conventional unit operations. Key metallurgical testingTesting completed to date at Sherritt International’s pilot plant facility includes continuous piloting of the leachingLeaching circuit and multiple batch purification campaigns to produce high-purity nickel sulphateNickel sulphate crystals.

Ni and Co are commonly extracted from laterite oresLaterite ore through sulfuric acidAcid leachingLeaching, and spent acidAcid is typically not recycledAcid recycle. Rather, acidAcid is often neutralized with limestone or hydrated lime, resulting in CO2 emissions and solid wastes. Bipolar membraneBipolar membrane electrodialysisElectrodialysis (BPMED) is an energy-efficient and safe method for acidAcid recyclingRecycling, but commercially available BPMED systems are designed for producing relatively dilute (up to 2 mol H+/L) acidAcid solutions. Higher concentration acidAcid streams are desirable in many metallurgical leach processes for decreasing reactor volumes and facilitating solid/liquid separations. To make acidAcid recyclingRecycling more feasible in Ni and Co extractive metallurgy, we are developing mechanisms for increasing output acidAcid concentration of BPMED systems toward 4 mol H+/L. Ore leachingLeaching experiments have been performed at bench scale to demonstrate the concept of process integrationIntegration with BPMED. Modified lateriteLaterites processing plantsProcessing plant incorporating these developmentsDevelopment can benefit from cost savings on reagent procurement, while adding revenue from byproduct magnesiumMagnesium hydroxide sales.

Draslovka has acquired the environmentally friendly GlycineGlycine LeachingLeaching TechnologyTechnology (GLT) to offer alternative hydrometallurgical solutions to the mining industry for recovering base and precious metalsMetals compared with traditional methods. This study presents an innovative alkaline leachingLeaching process, namely GlyLeach™, to extract Ni and Co from a flotationFlotation secondary cleaner tailingsTailings sample which would normally be considered as waste due to lack of an economical hydrometallurgical processHydrometallurgical processes. This material is rich in magnesiumMagnesium and iron silicates/oxides with 0.4% Ni and 0.01% Co in disseminated sulfide minerals. This paper covers the comprehensive studies involving 2 L tank leach tests and mini pilot runs to evaluate the performance of GlyLeach™ for extracting Ni and Co from this low-grade tailingsTailings sample. Once leached, the metalsMetals in solution were recovered via NaHS precipitationPrecipitation process which converted the Ni and Co in solution to a mixed sulfideMixed sulfide precipitate (MSP) while glycineGlycine previously complexed with these base metalsMetals was released back into solution to be recycled to leach fresh feed. LeachingLeaching tests showed 50–60% Ni extractionsNi extraction and over 33% Co extractionsExtraction under optimal leachingLeaching conditions, i.e., pH 10, 35% solids, 45–50 °C, oxygen flow rate at 0.1 L/min. The NaHS precipitationPrecipitation process achieved 98% Ni recovery as MSP with minimal impact on the free glycineGlycine concentration. This process has the potential to generate additional revenue from the flotationFlotation tailingsTailings “waste” stream that will not only increase the recovered metalMetals from such ores but also improve the economics of any flotationFlotation operation.

Hydrometallurgical refineries for cobaltCobalt and nickelNickel productionProductions have historically been built using stick-built construction methods, especially for primary extractionExtraction. The concept of using modularModular (ex-works) construction is gaining traction in chemical processing plantsProcessing plant. This construction method, or a hybrid thereof, is becoming increasingly popular. This is especially true for refineries located in remote areas where local specialized labor is scarce and in mini-refinery applications, which lend themselves to circular economy and recyclingRecycling types of projects. Examples include Northvolt and First CobaltCobalt. The research examines the advantages and disadvantages of modularModular and stick build approaches. ModularModular construction involves assembling prefabricated modules off-site and transporting them for on-site assembly. Conversely, stick-built relies on on-site construction using conventional methods. The analysis delves into aspects such as cost, time and skills availability, offering insight into the selection criteria for the various construction approaches. Unit operations that lend themselves to modularity are highlighted in the paper, including most tanks, mixer-settlersMixer-settler for solvent extractionSolvent Extraction (SX), certain thickeners and reagents. These units are identified as conducive to modularModular construction, contributing to improved assembly efficiency and reduced on-site work and risk. Analyses are conducted to establish the capital cost cross over point at which site constructed systems become more economical than an equivalent modularModular system as large plants are recognized as less amenable to modularity due to their substantial size. The study provides a technoeconomic analysis comparing costs and time between traditional stick build and modularModular approaches. This analysis aims to provide insights into the economic viability of these construction methods. Furthermore, the study addresses the time and cost implications associated with on-site work, offering a nuanced understanding of the efficiencies and drawbacks of each approach in this critical phase of hydrometallurgical refinery facility construction.

Heap leachingLeaching is a low costLow cost and inherently low carbonLow carbon footprintCarbon footprint process to recover nickelNickel and cobaltCobalt from laterite oresLaterite ore. In comparison with other processingProcessing methods for lateritesLaterites, it is a simple decoupled process that has a straightforward ramp-up to steady state productionProductions, allowing both lower capital and operating costs. Located in north-eastern Brazil, Brazilian NickelNickel’s (BRN) Piauí Nickel ProjectPiauí nickel project (PNP) heap leachHeap leach operation aims to be the first large scale commercial nickelNickel and cobaltCobalt heap leachHeap leach facility in the world. A small-scale commercial plant, the PNP 1000, produced first nickelNickel product in June 2022 and operated for 18 months producing mixed hydroxide product (MHP), which was qualified and sold to the electric vehicleElectric Vehicles (EVs) (EVElectric Vehicles (EVs)) market. The next scale of operations will be construction of the full scale plant to produce circa 25,000 tonnes per annum (tpa) NickelNickel (Ni) and 1000 tpa CobaltCobalt (Co) contained in an MHPMixed Hydroxide Precipitate (MHP). The PNP uses ion exchangeIon exchange technologyTechnology to separate and concentrate the value metalsMetals resulting in an MHP with less impurities and higher nickelNickel grades than MHP from high-pressure acidAcid leachingLeaching productionProductions. The MHP produced at PNP, containing nickelNickel and cobaltCobalt, is now the preferred product for the EVElectric Vehicles (EVs) batteryBattery market. MHP is easily re-dissolved, either to form sulphates or direct to precursor, for the cathode active materials for the EVElectric Vehicles (EVs) batteriesBattery. Advantages of heap leachingLeaching for EVElectric Vehicles (EVs) batteryBattery raw materials include lower capital intensity, lower operating costs, smaller environmentalEnvironmental footprint and reduced CO2 emissions. On the latter, the PNP has been independently benchmarked and will potentially produce one of the lowest carbon-intensity products in the nickelNickel industry, and BRN is looking at innovative ways to reduce or eliminate the CO2 emissions with a view to becoming a net carbon zero or even carbon negative producer. This results in the productionProductions of high-quality, sustainable nickelNickel and cobaltCobalt for the energy transition.

The growing demandDemand for cobaltCobalt (Co) and nickelNickel (Ni) in batteriesBattery and electronics necessitates efficient recovery from secondary sourcesSecondary sources like metallurgical wastes and spent lithiumLithium-ion batteriesBattery. Traditional methods, pyrometallurgyPyrometallurgy and hydrometallurgyHydrometallurgy, have drawbacks, including high energy consumption, hazardous emissions, and costly waste management. In contrast, bioleachingBioleaching is an eco-friendly alternative that uses microorganisms to extract metalsMetals through biochemical reactions, reducing energy use and harmful by-products. Certain bacteria, like Acidithiobacillus ferrooxidans, produce acidsAcid that dissolve metalsMetals, while fungi such as Aspergillus enhance recovery via organic acidAcid secretion. Key factors influencing bioleachingBioleaching efficiency include temperature, pH, and retention time. Despite its sustainabilitySustainability advantages, bioleachingBioleaching faces challenges like low recovery rates and inconsistent microbial activity, necessitating research in genetic engineering and process optimizationOptimization. This review examines the microorganisms, methods, and effectiveness of bioleachingBioleaching for Co and Ni recovery, comparing its sustainabilitySustainability with conventional technologiesTechnology and addressing challenges for large-scale applications.

Cobalt sulphateCobalt sulphate is a critical chemical for manufacturing batteryBattery cathodes. CobaltCobalt Blue has developed a flowsheetFlowsheet for refining cobaltCobalt intermediates into high purity cobalt sulphateCobalt sulphate. The process is amenable to simultaneously processingProcessing a wide range of cobaltCobalt intermediates and industrial by-products, including cobaltCobalt-nickelNickel hydroxides, cobaltCobalt-nickel sulphidesNickel sulphide, batteryBattery recycled product (black massBlack mass) and sea nodulesSea nodules. The flowsheetFlowsheet has been tested at pilot scale, with a commercial facility being developed near Perth, Australia. The process does not produce sodium sulphateSodium sulphate waste, which is common to refining operations. The capital and operating costs are lower, due to the use of a crystallisationCrystallization technique using isopropanolIsopropanol, instead of the more conventional evaporative technique employing draft-tube-baffle crystallisers.

Australia has had its issues with slow ramp up and poor design with first-generation high pressure acidAcid leachingLeaching (HPAL) plants such as Murrin Murrin (still operating), Cawse and Bulong. They failed to meet nameplate capacity and operating costs were higher than predicted. The second-generation plants such as Goro and Ravensthorpe were also problematic. Current nickelNickel prices are at an all-time low and even sulphide nickelNickel projects have closed due to current low nickelNickel prices. At the same time, IndonesiaIndonesia has now built three third-generation HPALHigh-Pressure Acid Leaching (HPAL) projects and is planning seven more. They are also building moreFerronickel ferro-nickelNickel projects using nickel lateritesNickel laterite processed by the rotary kiln electric arc furnaceElectric arc furnaces using low costLow cost Kalimantan coal as the fuel. The usual phases of project developmentDevelopment; namely feasibility, approval, construction and commissioning have also taken place in record time. Globally, there a number of HPALHigh-Pressure Acid Leaching (HPAL) projects in the pipeline but banks in particular are negative on funding and the projects are stalled particularly in Australia based on past HPAL projects.. For nickel sulphideNickel sulphide concentrates, pressure oxidationPressure Oxidation (POX) or Sherritt Gordon ammoniacal pressure leachingLeaching has been successfully applied, particularly in Canada, and the process has been continuously improved. Nickel sulphidesNickel sulphide are extracted from large open pit and underground sources and thus have higher capital and operating costs and generally longer developmentDevelopment timelines particularly underground mines. Brazil, Australia, New Caledonia, the Philippines and Africa have large reserves of lateritic nickelNickel but cannot currently compete with Indonesian low CAPEX and operating costs. This paper looks at why IndonesiaIndonesia has been successful with their HPAL plants and what is holding back the other projects being developed. Why has IndonesiaIndonesia been able to ramp up to design capacity in less than 12 months compared to an average of more than five years in other countries. It also investigates the potential environmentalEnvironmental impacts of this rapid developmentDevelopment.

Vale Base MetalsVale base metals have developed a process to produce battery grade nickel sulphateBattery grade nickel sulphate for a facility planned for the industrial park in BécancourBécancour industrial park, Québec, Canada. The facility is being designed for an annual capacity of 25,000 tonnes of Ni equivalent. This project is being developed to provide nickel sulphateNickel sulphate for General Motor’s batteryBattery supplySupply chain to power about 350,000 electric vehiclesElectric Vehicles (EVs) annually. The project is expected to begin operation in 2028. The facility will use high-purity, low-carbon nickelNickel from Vale Base MetalsVale base metals own refineries in Ontario and Newfoundland & Labrador. The process consists of sulphuric acidSulphuric acid dissolutionDissolution, under oxidizing conditions, of metallic nickelNickel to nickel sulphateNickel sulphate in fixed bed reactors, with flexibility to operate in different modes, depending on operational requirements, followed by acidAcid neutralization with suitable reagents, such as nickelNickel carbonate, to remove trace impurities prior to being sent to the customer for batteryBattery pre-cursor productionProductions in an integrated facility adjacent to the Vale plant. This paper outlines the key features and milestones in the process developmentProcess development.

In 2017, Kamoto CopperCopper Company (KCC) upgraded its refinery plant, transitioning from oxide concentrate processingProcessing to treating oxide ore using the Whole Ore LeachWhole ore leach method. This transformation included implementing a counter-current decantation (CCD) plant to remove water from the ore using low-grade (LG) raffinate as a wash solution. This approach optimized sulfuric acidAcid recyclingRecycling, thus significantly reducing quicklime and acid consumptionAcid consumption. However, subsequent efforts to ramp up productionProductions to achieve 300,000 tonnes of copperCopper cathode annually introduced new challenges. The acidAcid content in the LG raffinate began prematurely leachingLeaching copperCopper. The excess copperCopper inadvertently transported to the cobalt plantCobalt plant affected the iron, aluminum, manganese, and copperCopper (FAM-Cu) precipitates, which were recycled upstream to recover residual copperCopper. This led to a volumetric imbalance and reduced the residence time at FAM-Cu precipitationPrecipitation stages, which increased lime consumptionLime consumption triggering urgent plant upgradesUpgrade to fulfil the high lime demandDemand. These new changes resulted in disrupting quicklime slaking reaction further increasing quicklime consumption. To address all these issues, KCC and Glencore’s metallurgical teams implemented a comprehensive mitigation strategy. Key actions involved understanding the complex factors influencing quicklime consumption, enhancing ore quality control, improving laboratory practices, upgrading flowsheetFlowsheet by replacing LG raffinate reporting to the pre-leach plant with LG pregnant leach solution, and optimizing slaking conditions with stricter control. In parallel, a new control philosophy for the CCD circuit was introduced, focusing on optimizing thickener densities. These efforts resulted in substantial reductions in quicklime and acidAcid use, improved process stability, and increased cobalt recoveryCobalt recovery from 60 to 76%.

NewRange CopperCopper NickelNickel is developing significant copperCopper, nickelNickel, cobaltCobalt and platinumPlatinum group metalMetals (PGM)Platinum Group Metals (PGM) resources in northeastern Minnesota’s Duluth Complex. One aspect of NewRange’s future plan could include using the CESLCESL process to treat bulk nickel concentrateNickel concentrate to produce refined metalMetals products, including a PGMPlatinum Group Metals (PGM) concentrate in order to improve economics associated with these critical minerals. This presentation will discuss the opportunity for PGMPlatinum Group Metals (PGM) recovery using the CESLCESL process, including flowsheet developmentFlowsheet development, related testingTesting of the CESLCESL process, challenges around the PGMPlatinum Group Metals (PGM) recovery circuit and sulphurSulphur by product handling, and additional work required to derisk the process.

LeachingLeaching processes often are very corrosive and cannot be contained in metalMetals alloy vessels. The solution is to use liningLining systems that will protect the vessel from corrosionCorrosion. There are several different liningLining systems that can be considered. Understanding the advantages and limitations of the available systems will guide selection of the best system.

Fortune Minerals Limited (Fortune) is developing the vertically integrated NICO cobaltCobalt-gold-bismuth-copperCopper critical minerals project in Canada’s Northwest Territories (NICO ProjectNICO project). The principal objective is the productionProductions of cobalt sulphateCobalt sulphate heptahydrate destined for use in lithiumLithium-ion batteriesBattery. NICO has developed and tested a hydrometallurgical pathway to achieve this goal at the Lakefield Ontario laboratories of SGS Canada Inc. (SGS Lakefield). This paper describes that process as it was initially tested in 2012, summarizing the results of those tests and a subsequent validation pilot campaign in 2017 incorporating an improved option for manganese removal that produces a low sodium content crystallizationCrystallization feed.

CobaltCobalt is a key element in the productionProductions of lithiumLithium-ion batteriesBattery (USGS, Mineral Commodity Summaries 2022—Cobalt, USGS, 2022; Li and Lu in Science 367:979–980, 2020). With a large spike in cobaltCobalt demandDemand under way due to the rise in demandDemand for elections, especially electric vehiclesElectric Vehicles (EVs), new sources of cobaltCobalt need to be explored. CobaltCobalt is currently exclusively produced as a secondary product in other elemental mining operations, namely copperCopper and nickelNickel, and is therefore highly reliant on other metalMetals pricing for productionProductions. ProductionProductions is also dominated by the Democrat Republic of Congo, with refining equally dominated by China, making the supplySupply chain valuable to distribution. All this has resulted in the United States Department of Energy destinating cobaltCobalt as a critical mineral.

Prompt Gamma Neutron Activation Analysis (PGNAA)Prompt Gamma Neutron Activation Analysis (PGNAA) is a representative, real time, multi-elemental analysis technique suitable for digitalizing conveyed material flow composition. It has been used in the minerals sector for over 20 years to measure ore quality after primary crushing. High performance PGNAAPrompt Gamma Neutron Activation Analysis (PGNAA) allows an average analysis of each thirty seconds of conveyed flow to be determined. A high-performance system utilizes additional high-resolution detectors and digital multichannel analyzers to collect high spectral count rates of gamma ray energies emitted from elements over shorter timeframes with good measurement precisions being maintained. A configuration designed with a neutron source and comprehensive shielding is also safe to use as radiation levels are low and no access restrictions are needed during normal operation. Customized calibration and tonnage weighting of results provides more reliable data on conveyed material quality than available from any sampling protocol. Measurement data is utilized in various applications and case studies will show how these have been implemented at various mine sites. While proven in over a dozen commodities the technologyTechnology has not been widely implemented in the nickelNickel-cobaltCobalt industry despite these elements being easily measurable to low detection levels of tens of parts per million over thirty seconds increments. Applications discussed include bulk ore diversion to reject waste from plant feed for lateriteLaterites nickelNickel ore, measurement of nickelNickel at low levels to characterize and identify a waste rock type deleterious to a process in a copperCopper operation, and the use of nickelNickel measurement as a proxy in PGMPlatinum Group Metals (PGM) ore. NickelNickel measurement is also of interest in scrap steel processingProcessing as it, and chromium content, are characteristic of stainless-steel contamination in steel recyclingRecycling.

The MaturiMaturi project, located in the Duluth Complex of Minnesota and owned by Twin MetalsMetals Minnesota (TMM), a subsidiary of Antofagasta Minerals, is one of the world’s largest undeveloped Cu-Ni deposits containing approximately 9.0 Mt of copperCopper and 3.0 Mt of nickelNickel. Blue Coast Research conducted a number of metallurgical testwork programs on the deposit over the course of a decade (2012–2022) as the project was developed through scoping and pre-feasibility milestones. An optimized flowsheetFlowsheet of sequential flotationFlotation to produce copperCopper and nickel concentratesNickel concentrate was developed through this work. A comprehensive geometallurgical program was initiated in 2020 followed by a locked-cycle and mineral balancing program on carefully designed metallurgical domain composites. This work further enhanced the understanding of the metallurgical behaviour of the various value minerals in the flotationFlotation process on a spatial basis. By the time developmentDevelopment work on the project was suspended in 2022, the metallurgical knowledge of the deposit was highly evolved. This paper presents the evolution of metallurgical knowledge on the project from the early generalized performance of large representative composites to more granular spatial domain knowledge and understanding of individual mineral behaviour and flotationFlotation performance drivers gained from the geometallurgical process coupled with mineralogical balancing.

The recovery of the scandium (Sc) by-product from low-grade lateritic ore in Taganito HPALHigh-Pressure Acid Leaching (HPAL) NickelNickel Corporation (THPAL) using the existing and universal high-pressure acid leachHigh pressure acid leach (HPALHigh-Pressure Acid Leaching (HPAL)) technologyTechnology presents a strategic and innovative way for global competitiveness and for adding value, and scaling the global supplySupply for Sc as one of the critical minerals needed for achieving carbon neutrality. THPAL operates HPALHigh-Pressure Acid Leaching (HPAL) Plant in the Philippines and processes a low-grade lateritic nickelNickel ore, which was once considered mining waste. With design capacity of 30,000 t-Ni, the hydrometallurgical processing plantProcessing plant, produces an intermediate main product of nickelNickel/cobaltCobalt mixed sulfideMixed sulfide. Since the start of commercial operation in 2013, THPAL has achieved operating milestone not only in attaining the rated productionProductions but also in terms of initiating continuous improvement. To increase global competitiveness, THPAL has leveraged the effectiveness of HPALHigh-Pressure Acid Leaching (HPAL) technologyTechnology combined with new advanced technologyTechnology, leading to the recovery of Sc and chromite (Cr) as a by-product. Sc is a rare earth element and a critical mineral needed for carbon neutrality. Sc is mainly used in solid oxide fuel cells, a high-efficiency renewable energy technologyTechnology that creates electricity and contributes to the reduction of greenhouse gas emissionGreenhouse gas emissions. Another forward-looking application of Sc is as an alloying agent for aluminum (Al-Sc alloy), which can be used in the aerospace industry. While the current market demandDemand for Sc is relatively small and not wide, its potential in renewable energy technologiesTechnology like solid oxide fuel cells is significant. On the other hand, chromite is used as a raw material for stainless steel and other specialty steels after smeltingSmelting and processingProcessing into ferrochrome, an intermediate product, and is in wide demandDemand of the world. THPAL’s ability to provide a stable supplySupply of Sc and Cr could support advancements in carbon–neutral technologiesTechnology and help in achieving sustainabilitySustainability goals. The recovery of scandium and chromite from low-grade laterite oreLaterite ore further enhances the value of HPALHigh-Pressure Acid Leaching (HPAL) technologyTechnology. In the presentation, how THPAL leverages the effectiveness of existing HPALHigh-Pressure Acid Leaching (HPAL) technologyTechnology by integrating it with new advanced technologyTechnology to recover by-product will be explained.

SustainabilitySustainability is critical for nickelNickel business. The company aspires to responsible environmentalEnvironmental protection, social empowerment, and enhancing the well-being of its workers and host communities. It is not only ensuring the cultivating long-term values for the company but also committed to supporting the United Nations Sustainable DevelopmentDevelopment Goals (UN SDGs). NickelNickel commodity has entered a new era of critical metalCritical metals mining due to the increasing demandsDemand for batteryBattery raw materials in electric vehiclesElectric Vehicles (EVs), solar, and wind power plant technologiesTechnology. In the urge for green and digital transition, incorporating environmental, social, and governance principles within the mining and metalsMetals business chain has become critical to mitigate the risk within environmental and social aspects. The company aspires to responsible environmental stewardship, social empowerment, and enhancing the well-being of its workers and host communities to deliver long-term value. Besides the consideration of long-term value delivery on investment, the company has committed to sustainable mining practices which play pivotal roles in accelerating sustainable developmentDevelopment according to UN SDGs. NickelNickel Industries Limited (NIC) owns a portfolio in nickelNickel mining and low-cost downstream nickelNickel processingProcessing assets in IndonesiaIndonesia. NIC holds control of Hengjaya Mine, operating four rotary kiln electric furnaceElectric furnace (RKEFRotary Kiln Electric Furnace (RKEF)) projects, and acquired 10% interest in Huayou NickelNickel CobaltCobalt high-pressure acidAcid leachingLeaching (HPAL) project. NickelNickel Industries through Hengjaya Mine has demonstrated sustainable mining practices in environmental stewardship and social empowerment by being awarded the green rating in the Public Disclosure Program for Environmental Compliance in two consecutive years since 2022. In accordance with the NIC decarbonizationDecarbonization roadmap to cut emissions in half by 2035, the company also invested in Excelsior NickelNickel CobaltCobalt, a cutting-edge HPALHigh-Pressure Acid Leaching (HPAL) project to produce mixed hydroxide precipitateMixed Hydroxide Precipitate (MHP) in 2023. This HPALHigh-Pressure Acid Leaching (HPAL) project achieves the lowest carbon footprintCarbon footprint as compared to another existing project; it is 7–8 t CO2e/t-Ni. This investment is expected to reduce about 37% of NIC emission intensity from the 2022 target base year within its business chain portfolio.

Mixed hydroxide precipitate (MHP) isMixed Hydroxide Precipitate (MHP) an important nickelNickel- and cobaltCobalt-containing intermediate for producing batteryBattery-grade metalsMetals and salts. MetalsMetals are currently extracted and refined from MHP via complex hydrometallurgical processesHydrometallurgical processes, which are sensitive to feed material composition and require elaborate waste stream treatment. An improved flowsheetFlowsheet has been developed for selective extractionExtraction and refining of nickelNickel and cobaltCobalt MHP using the carbonyl processCarbonyl process. The process is highly selective in the extractionExtraction of nickelNickel and cobaltCobalt of varying feed compositions and is unaffected by high levels of deleterious elements (Cu, Mn, Zn). The carbonylation method, which has been used for many years for sulfide intermediate refining, is ideal for MHPMixed Hydroxide Precipitate (MHP) refining. A demonstration plant has been operated to demonstrate the technologyTechnology and derive engineering data for a full-scale productionProductions facility in the USA. The paper presents an overview of the process and describes the progress of building America’s first integrated nickelNickel refinery.

FromDevelopments and sustainability early exploration work at Soroako in the 1920s, to the subsequent studies under Government contract by PT Inco in the 1960s and more recent geological investigations, IndonesiaIndonesia now has large proven reserves of nickelNickel (Ni) as Ni lateriteLaterites—55 million tonnes (Mt) of contained Ni or 42% of world reserves, up from 16.2 Mt of Ni, or 11% of world Ni in 1995. Amid a Ni shortage and peak pricing in 2007, IndonesiaIndonesia began increasing Ni output, supported by the Government ban in 2009 on exporting un-processed Ni ore plus large Chinese investments. Ni laterite oreLaterite ore is currently processed in IndonesiaIndonesia by both pyrometallurgyPyrometallurgy and hydrometallurgyHydrometallurgy technologiesTechnology. Currently, there are twenty-two pyrometallurgical plants, with an installed capacity of 1.1 Mt of Ni as ferronickelFerronickel, Ni mattesMatte, and nickelNickel pig iron. There are six high-pressure acidAcid leachingLeaching (HPAL) plants with an installed capacity of 231,000 tonnes of contained Ni as mixed hydroxide precipitatesMixed Hydroxide Precipitate (MHP); total mined Ni in IndonesiaIndonesia was 1.8 Mt in 2023. There are a further ten potential HPALHigh-Pressure Acid Leaching (HPAL) plants either under design or in construction, having an estimated capacity of 619.5 thousand tonnes of Ni. Importantly, environmentalEnvironmental issues in Ni processingProcessing are also now under review by Government and industry. These include safe disposal of HPALHigh-Pressure Acid Leaching (HPAL) residues, carbon emissions, plant working conditions, and so on. This paper reviews progress and aspects in Ni productionProductions in IndonesiaIndonesia over the last decade and discusses important issues and expected changes over the coming decade.

MaxiFlox®MaxiFlox® R Series chemistry combined with SciDev’s engineering and professional services delivers a significant reduction in the treatment costs at a nickel lateriteNickel laterite processing plantProcessing plant in Australia. This has been achieved through a combination of reduced dosage consumption and increased underflow densityUnderflow density across a series of thickening stages on the front end of the circuit. ProcessingProcessing of a nickel lateriteNickel laterite to produce a mixed hydroxide product (MHPMixed Hydroxide Precipitate (MHP)) is a complex process from beneficiationBeneficiation, leachingLeaching and selective precipitationPrecipitation. The limonite component of the ore body passes through beneficiationBeneficiation, thickening, pre-heat thickening, pressure acidAcid leach, atmospheric leach), counter-current decantation to the precipitationPrecipitation and bagging circuits. The saproliteSaprolite component is separated at the start of the process, thickened, pre-leached and combined with the leached limonite slurry in atmospheric leach. The role of dewatering in this complex process increases plant throughput whilst reducing acid consumptionAcid consumption as a function of slurry dilution. In this case, critical to the success of the clients operation is low flocculantFlocculant dosages and high-density thickener underflows. There is also a requirement to minimise the underflow yield stressYield stress due to pumping requirements. The key challenges identified for our client in achieving these success criteria are as follows: (1) process water quality and high salinity levels > increases required flocculantFlocculant dissolutionDissolution time; (2) feed variations due to the variable ore body; (3) no automated flocculantFlocculant dosage control on the thickeners, with operations personnel being conservative to ensure over flocculation of the thickener in case of rapid change in processingProcessing efficiency; (4) minimise thickener underflow yield stressYield stress whilst maximising the density to ensure pumping efficiency. Understanding these challenges, SciDev was able to present a solution through a combination of tailored flocculantFlocculant chemistry, an experienced team of engineers delivering valued professional services and introduction of an automated dose control system offering valued benefits to the client.

The increasing demandDemand for base metalsMetals, such as nickelNickel and cobaltCobalt, is driven by their roles in electric vehiclesElectric Vehicles (EVs) and renewable energy technologyTechnology markets and requires innovative solutions to reduce project timelines and costs. Modularizing Glencore’s Jameson concentrator technologyTechnology marks a significant advancement in achieving these objectives in metalMetals recovery plants. The Jameson cell’s high-efficiency flotationFlotation process effectively captures fine nickelNickel and cobaltCobalt particles, and the low profile, high intensity grinding environment provided by the IsaMill produces the highest power input per unit volume in minerals processingProcessing applications. By modularizing these technologiesTechnology, compact, prefabricated units can be constructed offsite, significantly reducing on-site setup time and infrastructure needs. These modularModular units simplify installation and decrease labor costs while supporting incremental scalability, allowing capacity adjustments to meet market demandsDemand without major site modifications. EnvironmentalEnvironmental and logistical benefits further strengthen this approach: the compact design reduces the plant’s physical and environmental footprint. Additionally, modularModular units can be relocated to remote sites, improving cash flow and reducing capital costs associated with site-specific infrastructure. This study highlights the economic and operational advantages of modularized Jameson concentrator technologyTechnology, demonstrating how it accelerates plant readiness, reduces capital cost, and supports sustainable, scalable growth in base metal recoveryBase metal recovery.

The Baptiste deposit is a large tonnage, low-grade, near surface, nickelNickel deposit located in central British Columbia, Canada, that is currently being developed by FPX NickelNickel Corp. Baptiste is a serpentinized ultramaficUltramafic deposit that, critically, was near barren in sulfurSulphur during mineral alteration resulting in the formation of awaruiteAwaruite, a metallic nickelNickel-iron alloy (Ni3Fe), as the dominant nickelNickel mineral. AwaruiteAwaruite has a high nickelNickel content, is highly ferromagnetic, has a high specific gravity, is malleable, and is readily amenable to froth flotationFlotation. Each of these properties plays a role in the mineral processingProcessing flowsheetFlowsheet which results in the productionProductions of a 60% Ni concentrate. The awaruiteAwaruite mineral concentrate is of sufficient grade and purity to be used directly in stainless-steel productionProductions as a low-carbon intensity replacement of ferronickelFerronickel or, in select instances, of Class 1 nickelNickel. Alternatively, the awaruiteAwaruite mineral concentrate can be refined to a high purity nickelNickel product to meet the growing demandDemand from the batteryBattery electric vehicleElectric Vehicles (EVs) supplySupply chain. Part 1 of this chapter summarizes the mineral processingProcessing developmentsDevelopment of the Baptiste NickelNickel Project while Part 2 summarizes the hydrometallurgical refinery of the awaruiteAwaruite mineral concentrate to high purity nickel sulfateNickel sulphate.

The rapid expansionExpansion of the electric vehicleElectric Vehicles (EVs) market and the dominance of nickelNickel-manganese-cobaltCobalt batteryBattery chemistries have altered global nickelNickel dynamics, driving volatile supplySupply-demandDemand equilibriums and commodity pricing. Traditionally tied to steel and stainless-steel productionProductions, nickelNickel now faces dual pressures from declining Chinese steel demandDemand and evolving batteryBattery chemistries, such as the rise of lithiumLithium-iron-phosphate batteriesBattery. GeopoliticalGeopolitical challenges further complicate supplySupply chains, with IndonesiaIndonesia, the largest global supplier’s export restrictions and lack of existing Biden Administration U.S. Inflation Reduction Act compliance, forcing North American manufacturers to look for alternative avenues for supplySupply. While opportunities exist in domestic mining, international strategic partnerships, and nickelNickel recyclingRecycling, these solutions face barriers such as regulatory delays, high costs, and limited government support. Addressing these challenges will require strategic investments, streamlined approvals, and industry collaboration to ensure North AmericaNorth America can meet the growing demandDemand for nickelNickel in a competitive and sustainable manner.

Since 2000, the tonnage and sourcing of primary nickelNickel (Ni) has changed dramatically: global primary mined Ni has almost tripled to 3.9 million tons mined in 2024. Canada’s share of world mined Ni has dropped from about 15% to about 3% in 2024. IndonesiaIndonesia’s share of the global Ni supplySupply has increased by about 8% in 2000 to over 63% in 2024 at low costLow cost, which is having a negative impact on other producers and is upsetting the global market. Low Ni pig iron productionProductions continues to upset market forces. DemandDemand from electric vehiclesElectric Vehicles (EVs) has slowed; with the Ni demandDemand for batteriesBattery depressedElectric vehicles batteries, the Ni price has weakened. In IndonesiaIndonesia, new plants have typically duplicated the conventional plant design with minimal change; less attention is also paid to environmentalEnvironmental conditions. On the other hand, several promising, technically innovative projects, representing 6% of world Ni at start-up in Ni-rich New Caledonia, have failed to deliver anticipated tonnages and profitability, with the result that either productionProductions has been considerably curtailed, or plants have been placed on care and maintenance. This chapter explores and discusses these changes, reviews current pyrometallurgical operating plants, the impact of the export ban of ore from IndonesiaIndonesia, and the technologiesTechnology used. In addition, changes, and improvements in technologyTechnology (such as net zero technologiesNet zero technologies and use of artificial intelligenceUse of artificial intelligence) and efforts to lower CO2 emissions will be discussed, and ideas for Ni productionProductions over about the next decade will be offered. The chapter title was inspired by a paper having a similar title by the late Paul E. Queneau and published 57 years ago describing the vastly changing Ni scene in 1968, when Canada produced over 70% of the world’s mined Ni, and several new lateriteLaterites Ni plants would soon come on-line.

Recently, as the productionProductions of electric vehiclesElectric Vehicles (EVs) has rapidly increased, the productionProductions of lithiumLithium-ion batteriesBattery containing high-purity valuable metalsMetals (Ni and Co) is required. The number of end-of-life lithiumLithium-ion batteriesBattery has rapidly increased; therefore, there is a need to improve environmentalEnvironmental issues. However, there are limits to process changes for removing impurities and achieving high purity of diversified recycled resources in hydrometallurgical processHydrometallurgical processes for recyclingRecycling of end-of-life lithiumLithium-ion batteriesBattery. Therefore, a transition to hybrid process capable of mass productionProductions is required, and the research was conducted on matte smeltingMatte smelting and purificationMatte purification process using recycled resources. Ni and Co contained in various resources were recovered using molten iron in high-temperature smeltingSmelting process. The recovery behavior depending on the type of resource by carbon content was compared with the thermodynamic calculations using FactSageFactSage 8.2™. The alloy containing Ni and Co was concentrated through addition of sulfur and oxygen blowing and smelted into matteMatte with improved concentration of Ni and Co. An aqueous solution containing Ni and Co was obtained through a pressure oxidationPressure Oxidation (POX) leachingLeaching, and it was confirmed that the Ni and Co recovery rates were closely related to the oxidation–reduction potential and pH of the pregnant leachingLeaching solution. The leachate was highly purified into Ni and Co compound through a neutralization process, and the impurity concentration in the Ni and Co compound was maintained below 0.5%. In order to develop the matte smeltingMatte smelting and purification process utilizing recycled resources, process condition was established by METSIM engineering software.

Thermodynamic calculations using thermodynamic software packages like FactSageFactSage have emerged as a valuable tool for optimizing pyrometallurgical processes. A review of the chemistry and process conditions is presented for several Ni and Co processes, including sulfide and lateriteLaterites smeltingSmelting, as well as battery recyclingBattery recycling. In the presentation, examples of FactSageFactSage calculations and highlights of limitations and inaccuracies in the existing models are to be presented. In this extended abstract, we describe a procedure for enhancing model predictions through a targeted experimental study. An example is provided to quantify the effect of Al2O3 concentration in slagSlag on the solubilitySolubility of nickelNickel. The experimental procedure involves planning targeted experiments, high-temperature equilibration, quenching, and electron probe X-ray microanalysis, followed by the revision of interaction parameters in the thermodynamic model.

BolidenBoliden's vision is to be the most climate friendly and respected metalMetals provider in the world. CO2 emissions are one strategic area where BolidenBoliden has the ambitious target of reducing absolute carbon greenhouse gas (GSG) emissions by 42% by 2030 (Scope 1 and 2) and by 30% (scope 3), with 2021 as the base year. To lead the industry, BolidenBoliden has introduced green transitionGreen transition metalsMetals (GTM)Green metals to the global market. GTM are a portfolio of recycled and low-carbon metalsMetals from BolidenBoliden’s own mines or 100% recycled material from its smelters. The GTM portfolio includes low-carbon zinc, recycled zinc, low-carbon copperCopper, recycled copperCopper, low-carbon lead, recycled lead, and low-carbon sulfuric acidAcid. In 2024, BolidenBoliden launched low-carbon nickelNickel with a minimal carbon footprintCarbon footprint, measuring less than 5 kg of CO2e per kg nickelNickel (reference year 2021)—well below the global average of over 34 kg of CO2e per kg nickelNickel equivalent in 2024. The purpose of this article is to explain how the BolidenBoliden Harjavalta Nickel SmelterNickel smelter has achieved a reduction in its carbon footprintCarbon footprint while increasing its smeltingSmelting capacity by 60 kt to a total of 370 kt per year. These improvements were the result of two key developmentDevelopment projects, which were commissioned in two phases, with the first part in 2017 and the second in 2021. The primary goals included increasing smeltingSmelting capacity, extending the flash furnace campaign lifeCampaign life, and enhancing environmentalEnvironmental performance, process control, and operational safety.

This work reported the experimental liquidusLiquidus studies of the ternary Ni–Sn–S system. It aims to improve the existing thermodynamic prediction power in a 20-component system for complex pyrometallurgical processes during refining, recyclingRecycling, and recovery stages. An elevated temperature equilibration and quenching in brine techniques were adopted, followed by direct elemental measurements of the quenched phases using an electron probe microanalyzer (EPMA) equipped with wavelength dispersive spectrometers. The accuracy of the work was ensured by 4-point assessments. MatteMatte (SnS- and NiS-rich), liquid metalMetals, S-free MeX (Ni1+xSn), Ni3Sn (high- and low-temperature), FCC-Ni, Sn-containing β-Ni3S2Β-Ni3S2, Ni1−xS (Ni-pyrrhotite), NiS2, Ni3Sn4, SnS, Sn2S3, SnS2, and Ni3Sn2S2Ni3Sn2S2, along with their primary phase fields, were found. The miscibility gapMiscibility gap expands from the Sn–S binary to the Ni-rich side with two saddle points. Ni3Sn2S2Ni3Sn2S2 is an incongruently melting ternary compound with low compositional variation (stoichiometric) at liquidusLiquidus. Nineteen invariant reactions (syntectic, peritectic, quasi-peritectic, and eutectic types) and seven saddle points were determined.

The main objective of the furnace start-upFurnace start-up is to gradually heat, dry and expand the working liningLining to the extent that all the brick joints are closed before they are exposed to molten material. Once the bricks are considered tight under the electrodes, a molten bath can slowly be created and grown to normal operating levels. The major key consideration to achieve these goals is careful monitoring and controlling of temperature rise rates within defined rates. The heat up process can be divided into 4 phases: burner refractoryRefractory preheat or dry out, electrical refractoryRefractory preheat, molten bath formation and hearth expansionExpansion stabilization and electric ramp up to name plate. The control and operation of the furnace vary for each phase, and the decisions to switch from one phase to the next are made based on continuous observations of conditions in the furnace (via monitoring of temperature, bath level and expansionExpansion). This paper offers detailed guidelines for the heat up process of electric arc furnacesElectric arc furnaces, but it cannot address every potential issue that may arise. Some challenges may be specific to individual start-ups. While it can serve as a foundation for developing a heat up manual, it should not be used as the sole reference for actual operations.

Electrode consumptionElectrode consumption in electric furnaceElectric furnace smeltingSmelting of non-ferrousNon-ferrous matteMatte and metalsMetals has now been reported for over a century, involving carbon prebakePrebake and self-baking Söderberg pasteSöderberg paste electrodes, and more recently including performance using graphiteGraphite electrodes. This non-ferrousNon-ferrous electric smeltingSmelting has encompassed: copperCopper, nickelNickel and nickelNickel-copperCopper platinumPlatinum group metalMetals electric furnaceElectric furnace sulfide matte smeltingMatte smelting; hot liquid overflow matteMatte settling and reductive slagSlag cleaning; historically some melting and smeltingSmelting of copperCopper and cobaltCobalt metalMetals (the latter by selective carbothermic reduction of solid cobaltCobalt-bearing slagsSlag); and nickel lateriteNickel laterite electric furnaceElectric furnace smeltingSmelting, to produce both crude and refinedFerronickel ferro-nickelNickel. Historical electrode consumptionElectrode consumption will be reviewed from the 1900s to present, to explore key trends in electrode developmentDevelopment and associated improvements in consumption. The different electrode types adopted in the electric smeltingSmelting and refining of each of the different non-ferrousNon-ferrous commodity types and associated impact on electrode consumptionElectrode consumption will be compared. Benchmarks of specific electrode consumptionElectrode consumption rates reported in kg/MWh (and kg/t) will be presented. These can help to guide increases in efficiencies and further improvement and lowering of electrode consumptionElectrode consumption, and associated CO2 emissions, in pursuit of still more sustainable non-ferrousNon-ferrous electric smeltingSmelting of copperCopper, nickelNickel and cobaltCobalt in future.

The MetalsMetals Company (TMC) hasDeep-sea nodules generated a world-class project with the developmentDevelopment of a flowsheetFlowsheet that enhances the project business case, has streamlined developmentDevelopment costs and execution timelines by years, minimizes capital and risk and generates nearly zero solid waste. The flowsheetFlowsheet was developed over a five-year period through execution of cost-effective strategic metallurgical approaches culminating in commercial-scale demonstrations at the Pacific MetalsMetals Company (PAMCO, Japan) and small-scale productionProductions of high-purity nickelNickel and cobaltCobalt sulfatesSulfate. High-grade deep-sea polymetallic nodulesPolymetallic nodules, found in vast quantities in the Clarion-Clipperton Zone of the Pacific Ocean, are emerging globally as the largest undeveloped resource of base and batteryBattery metalsMetals. The unique composition of the nodules, namely the combination of nickelNickel, copperCopper, cobaltCobalt and manganese in hydroxide form, allowed The MetalsMetals Company the luxury of considering a broad spectrum of processingProcessing options. Conceptually, deep-sea polymetallic nodulesPolymetallic nodules can be processed through hydrometallurgical or pyrometallurgical flowsheetsFlowsheet with various equipment and mechanistic pathways within these fundamental options. The present paper describes the strategic metallurgical approaches employed and outlines the technical and commercial developmentDevelopment pathways that generated this high value outcome of low-capital, low-risk processingProcessing with high recoveries, an attractive product portfolio, all while generating nearly zero solid waste. These metallurgical strategiesMetallurgical strategies were: (a) FlowsheetFlowsheet selection based on meeting carefully developed company and project objectives in a non-biased manner with a value driven mindset, (b) Sequential technical developmentDevelopment—literature reviews, bench-scale testwork, concept engineering and costing, pilot campaigns, commercial strategies and agreements, culminating in a tolling agreement and commercial-scale demonstrations at PAMCO’s existing facility in Japan. (c) Progressive commercial scope and saleable product strategy that managed the scope of facilities, capital availability and risk—get into business with the first saleable product then progressing downstream to more value-added products using cashflow from early operations. ThisValue generation in metallurgy flowsheet developmentFlowsheet development model, through serendipity and design, enabled the opportunity to process the nodules through existing world-class facilities, eliminating the requirement for a greenfield capital project and only entailing payment of operating expenses, realizing significant value. Further advantages of the strategy include utilization of existing assets and experienced personnel that are underutilized following the disruptive rise and cost dominance of Indonesian nickelIndonesian nickel processingProcessing operations.

Polymetallic nodulesPolymetallic nodules containing useful metalsMetals such as Co, Ni, Cu, and Mn are widely found on the seafloor at water depths ranging from 4000 to 6000 m. SmeltingSmelting of these nodules produces matteMatte with a Ni, Co, and Cu content of 30%, 3%, and 20%, respectively, which is difficult to process in Ni matteMatte refineries owing to the high Ni-to-Cu ratio. Hence, this matteMatte needs to be separated into Cu-rich and Co–Ni-rich mattesMatte to be processable at existing smeltingSmelting and refining facilities. This can be performed via a slow-cooling process for liquid–liquid separation and subsequent growth of separate matteMatte grains for their easy separation into the two types of matteMatte. This paper describes the investigation of the effect of the cooling rate and the composition of the starting matteMatte, which was simulated to match that expected for a matteMatte obtained from polymetallic nodulesPolymetallic nodules, on the matteMatte obtained via slow coolingSlow cooling. The precipitates were roughly classified into three phases: copperCopper sulfide, nickel sulfideNickel sulfide, and mixed sulfideMixed sulfide phases. The grain size of the copperCopper sulfide phase increased with decreasing cooling rate. The results suggest that the matteMatte can be separated into multiple concentrates via mineral processingProcessing.

In 2018, KazChrome's Furnace No. 4-3 at Workshop No. 4 in Aktobe, Kazakhstan, exhibited unusually high temperatures in the hearth region of the furnace liningLining. To investigate the cause, pyrometallurgical experts conducted a comprehensive assessment, including physical measurements, thermal modeling, and Acousto Ultrasonic-Echo (AU-E) non-destructive testingTesting (NDT) of the hearth and sidewalls. AU-E inspection results provided direct thickness measurements, revealing that only 40% of the original refractoryRefractory thickness remained in the hearth. NDT findings indicated severe compromise of the working liningLining layer, with signs of delamination and potential floatationFlotation. Based on these results, a full hearth relining was deemed necessary to restore furnace integrity. This paper presents the detailed investigation conducted by KazChrome and Hatch furnace specialists, outlining the assessment methodologies, key findings, and the decision-making process that led to the reline of Furnace No. 4-3.

The traditional high-grade sulfide mineral reserves are depleting, shifting the research focus towards ultramaficUltramafic resources since they are available in copious amounts and could meet the growing nickelNickel (Ni) demandDemand. Even though ultramaficUltramafic ores were discovered in the early 1920s, they have remained a resource due to the unavailability of economically viable methods for upgrading them. The ultramaficUltramafic ores are characterized by low-grade (0.4–0.8 wt.% Ni) and asbestos materials, posing safety, health, and environmentalEnvironmental risks. Moreover, their high MgO has detrimental effects on subsequent processes. The MgO affects flotationFlotation by slime coating, leachingLeaching by consuming a portion of the acidAcid, and smeltingSmelting by forming a viscous slagSlag, negatively affecting furnace integrity. In this work, our research group investigates a promising thermal upgradingThermal upgrading method for ultramafic concentratesUltramafic concentrate, which involves the addition of an iron (Fe) source to the concentrate, followed by heating the mixture to approximately 920 °C. During this heating process, the added Fe reacts with sulfur (S) to form nonmagnetic FeS, while Fe and nickelNickel (Ni) form magnetic FeNi. The key benefits of the process are the use of lower operating temperatures compared to conventional methods and a product suitable for subsequent physical separation based on magnetism differences. Our initial findings suggest that higher temperatures promote the formation of large FeNi particles, which enhance subsequent magnetic recovery. Although we have conducted extensive experimental investigations on the FeNi growth mechanism as a function of temperature in our previous work, further experiments are necessary to correlate Ni extractionNi extraction with FeNi growth to strike a balance between high Ni extractionNi extraction and magnetic recovery.

TheFerronickel slag productionProductions of high-grade FerronickelFerronickel (FeNi) using the Rotary Kiln Electric FurnaceElectric furnace (RKEFRotary Kiln Electric Furnace (RKEF)) process is typically a CO2 emissions-intensive operation. However, FeNi slagSlag is an untapped high-quality energy source that if harnessed can be used to reduce the plant’s carbon footprintCarbon footprint. Conventionally, FeNi slagSlag is either molten hauled and dumped or water granulated leading to a loss of up to 100 MW of sensible heat in the case of an 85 MW electric furnaceElectric furnace. Air granulationAir granulation uses a high-velocity jet of air to granulate molten slagSlag, enabling slagSlag heat recoveryHeat recovery through the generation of hot off-gas and high surface area slagSlag granules. High-quality heat can be recovered and used to offset fuel requirements in the drying or calcination steps or even to generate electricity, offsetting the emissions from coal-fired power plants. In this paper, the use of air granulationAir granulation to reduce greenhouse gas emissionsGreenhouse gas emissions was evaluated for a generic RKEFRotary Kiln Electric Furnace (RKEF) FeNi plant with an 85 MW furnace.

The growing trend in electric vehiclesElectric Vehicles (EVs) has led to an increasing demandDemand for Class 1 nickelNickel, particularly nickelNickel sulfateSulfate, one of the critical raw materials for batteryBattery precursors. Existing pyrometallurgical technologyTechnology enables ferronickelFerronickel conversion to nickel matteNickel matte with elemental sulfur addition. Elemental sulfur, however, could potentially be replaced by alternative source of sulfur, such as gypsum (CaSO₄·2H₂O), which is more cost-effective. This study investigates the effects of process temperatures, gypsum content, and coal content in the feed on the conversion of ferronickelFerronickel to low-grade nickel matteNickel matte. Thermodynamic simulations of ferronickelFerronickel conversion to low-grade nickel matteNickel matte using gypsum and coal were conducted using FactSageFactSage 8.0 software. Furthermore, laboratory-scale experiments were conducted by melting mixtures composed of 1.5 g of ferronickelFerronickel, gypsum (ranging from 10 to 90% of the ferronickelFerronickel’s weight), and coal (at 1–2 times the stoichiometric requirement for gypsum decomposition). The mixture was placed in a magnesia (MgO) crucible and melted for 180 min under an inert argon atmosphere. The temperatures were varied between 900 °C and 1500 °C. The melting products were quenched and were analyzed using scanning electron microscopy-energy dispersive spectroscopy, and electron probe X-ray microanalysis. The findings provide insights into the effects of process temperature, gypsum content, and coal content in the feed on the phase formation and quality of the resulting low-grade nickel matteNickel matte.

The nickelNickel slagSlag cleaning process in an electric furnaceElectric furnace (EF) utilizes coke—a fossil carbon source—as a reductant to recover valuable metalsMetals from flash smeltingFlash smelting furnace slagSlag as an EF matteMatte via physical settling processes and chemical reduction. The process annually produces considerable amounts of direct fossil CO2 emissionsFossil CO2 emission reduction and depends on coking coal, a critical raw material in the European Union, which highlights the need for alternative and more sustainable reductants. In this study, biochar, a product derived from thermochemical conversion of biomass, was investigated in large laboratory-scale nickelNickel slagSlag reduction experiments with 100 g sample size. The experiments were conducted at 1350 °C and 1400 °C under inert N2-Ar gas atmosphere testingTesting 100% coke, 100% biochar and 50% / 50% biochar/coke mix. The reduction times were 10, 30, 60, 90 and 120 min, the samples were water-quenched or water-granulated and analyzed using SEM–EDSScanning Electron Microscopy–Energy Dispersive Spectroscopy (SEM-EDS) and LA-ICP-MSLA-ICP-MS. The slagSlag phase formed had homogeneous, glassy areas as well as heterogeneous areas with crystalline microstructure and was depleted of valuable metalsMetals as most of them deported to a heterogeneous matteMatte phase. To estimate the recovery possibilities of Ni and Co, matteMatte/slagSlag distribution coefficientsDistribution coefficient were calculated. The findings suggest that biochar is a promising alternative reductant to coke in the nickelNickel slagSlag cleaning process, as it either performed better than or equally well as coke for Ni and Co recovery.

Following the compromised integrity of BolidenBoliden Harjavalta’s NickelNickel Electric FurnaceElectric furnace (NiEF) in 2019, Hatch was awarded the project to redesign the furnace crucible (including structural steel, refractoryRefractory, and coolers) with a focus on operational safety and improved reliability of the crucible. The key features of the custom-designed furnace include robust cast-in-pipe cooling, vertical binding system with online load monitoring, and roof components facilitating ease-of-maintenance, combined with maximizing the available footprint in the existing smelter building to facilitate the planned increase in productionProductions. The new NiEF was rebuilt and started up in late 2021 as part of smelter upgradesUpgrade to produce reduced carbon footprintCarbon footprint nickelNickel and facilitate higher throughput. BolidenBoliden and Hatch teams continued to work together following startup to ensure the performance and reliability of the equipment met the availability requirement of the Flash SmeltingFlash smelting Furnace upstream. Hatch provided ongoing monitoring of equipment condition with data-driven analysis and projections to support timely decisions regarding operational risks and campaign lifeCampaign life. BolidenBoliden and Hatch were able to improve operations through implementation of automated matteMatte tapping, improved process stability, and transitioned to condition-based maintenanceCondition-based maintenance practices. The data collected throughout the campaign along with updated operation and maintenance practices were utilized to support the planned 2025 furnace reline while minimizing risk and downtime.

Global demandDemand for critical minerals will continue to increase as the world moves towards electrification and batteryBattery storage, with battery materialsBattery materials being a major driver for nickelNickel and cobaltCobalt demandDemand. Concurrently, global reserves of high-grade Ni and Co ores are declining, and the supplySupply of these metalsMetals is increasingly regionally concentrated: > 70% of cobaltCobalt is mined in the Democratic Republic of Congo and > 50% of nickelNickel is mined in IndonesiaIndonesia. DemandDemand for new sources and a diversified supplySupply chain has renewed interest in deep-sea mining of polymetallic nodulesPolymetallic nodules as an alternative source of critical minerals, particularly Cu, Ni, Co, Mn, and rare earth elements (REE). There has been considerable research and developmentDevelopment related to the sustainable harvesting of nodules from the seabed, and attention to the extractionExtraction of critical minerals from the harvested nodules has recently regained momentum. Advancements in process technologyTechnology are required to extract value from these nodules, specifically extractionExtraction flowsheetsFlowsheet for Ni and Co that are environmentally and economically competitive with land deposits. Potential processingProcessing routes to produce Ni and Co from sea nodulesSea nodules, as well as other by-products, are reviewed here. Commentary is also provided on the relative advantages of hydrometallurgical, pyrometallurgical, and combined hydrometallurgical and pyrometallurgical processingProcessing technologiesTechnology, along with the inherent processingProcessing challenges presented by this unique resource.

The increasingLithium-ion battery recycling demandDemand for batteriesBattery, particularly in the electric vehicleElectric Vehicles (EVs) industry, has led to a surge in the need for critical metalsCritical metals, including nickelNickel (Ni). It is projected that the demandDemand for Ni will exceed the existing primary supplySupply by 2029, with an estimated supplySupply shortage of 440,000 tonnes by 2031. This projected gap between supplySupply and demandDemand has promoted interest in Ni extractionNi extraction from resources that are technically challenging and not financially attractive today, including low-grade Ni laterite oreLaterite ore (< 1 wt.% Ni) and spent lithiumLithium-ion batteriesBattery (LIBsLithium Ion Batteries (LIB)). Currently, over half of the primary Ni supplySupply is commercially produced by processingProcessing Ni laterite oresLaterite ore through pyrometallurgical and hydrometallurgical routes for use in the stainless steel and batteryBattery markets. Most processed lateriteLaterites deposits have Ni content typically between 1.3 and 2.5 wt.%. However, ore grades are declining globally, requiring the Ni industry to look beyond conventional technologiesTechnology. Ni has extensive use in lithiumLithium nickelNickel manganese cobaltCobalt oxide and lithiumLithium nickelNickel cobaltCobalt aluminum oxide LIBsLithium Ion Batteries (LIB) with the cathode material consisting of LiNixCoyMn1−x−yO2 and LiNixCoyAl1−x−yO2, respectively. The projected ramp up in the number of end-of-life batteriesBattery by 2030 highlights the need to develop recyclingRecycling technologiesTechnology to address the environmentalEnvironmental impacts and alleviate supplySupply chain shortages. The synergy between the nickelNickel oxides in LIBsLithium Ion Batteries (LIB) and lateriteLaterites deposits presents an opportunity to accelerate their developmentDevelopment by learning from and combining advancements in each field. This paper reviews the existing processingProcessing routes developed for the extractionExtraction of Ni from low-grade laterite oreLaterite ore and spent LIBs. It highlights how these developmentsDevelopment are influenced by conventional lateriteLaterites processingProcessing technologiesTechnology. Additionally, this review provides insights into how battery recyclingBattery recycling can be integrated into existing Ni smelters/refineries and the techno-economic benefits of this integrationIntegration.

Generally, lateritesLaterites and sulfides ores are the major sources of nickelNickel (Ni) and cobaltCobalt (Co) and contain impurities metalsMetals including Fe, Al and Cr. Ni and Co are extensively used in lithiumLithium-ion batteryBattery manufacturing as a critical element in cathode materials, requiring high-purity metalMetals salts as a precursor. Hydrometallurgical processesHydrometallurgical processes including sulfuric acidAcid high-pressure leachingHigh pressure leaching, nitric acidAcid pressure leachingLeaching, atmospheric leachingLeaching, and the sulfation-roasting-leachingLeaching processes have high recovery rates of valuable Ni & Co along with low value/waste Fe. These processes typically have high capital & operating costs (i.e., autoclavesAutoclave) due to aggressive operating conditions (250–270 °C; 4–5 MPa). Iron is typically the main impurity in the ores and adds to the operating costs due to additional acid consumptionAcid consumption during leachingLeaching, slow Fe extractionExtraction process, costly processes to recover Fe as a by-product to offset process costs (i.e., Fe pyrohydrolysis or hydro-hydrolysis), or waste disposal issues of iron hydroxides. The purpose of this study was to develop a modified hydrometallurgical approach that maximizes Ni, Co, and Cu recovery, while minimizing Fe co-dissolutionDissolution through selective leachingSelective leaching. The first part of the study was performed on a Cu-Ni sulfide concentrate which was ground to – 140 mesh and mixed with various additives which included Na2SO4 for a sulfation reaction, NH4Cl for a chlorination reaction, and roasted at temperatures of between 250 °C and 650˚C for a specified residence time and heating rate. Following the roasting process, the treated ore was leached with deionized (DI) water and in several cases with additives at 65–95 °C for 5 h. Under certain sulfidation conditions, it was found that the leachingLeaching efficiencies for Co, Cu & Ni were 100.0%, 89.2% & 68.0%, respectively, with little to no Fe extractionExtraction in the leach solution. For chlorinated ores improved leachingLeaching efficiencies for Co, Cu, and Ni were observed with 100.0%, 95.0%, and 98.8% extractionExtraction respectively with 3.8% Fe extracted in the leach solution. During roasting, conversion of Fe (II) into Fe (III), which inhibited iron dissolutionDissolution in water leachingLeaching such that Co, Cu, and Ni are selectively leached over trivalent metalsMetals.

FerronickelFerronickel matteMatte is produced pyrometallurgically by PT Vale IndonesiaIndonesia from lateritic ores. The ore is initially dried and calcined in rotary kilns, where Ni and Fe are partially reduced. Molten sulfur is added to the kiln, where it vaporizes and reacts with the metalsMetals in the calcineFerronickel calcine to produce sulfides. This sulfur-loaded calcine is then melted in Electric Arc furnacesElectric arc furnaces to produce crude nickel matteNickel matte, which is further refined in downstream converters. Little is known about the reaction kinetics of calcine with sulfur gas. This study investigates the effects of sulfur gas injection into calcine beds, focusing on sulfur fixation rates and maximum loading capacity of the calcine. Two types of crucibles were built (disk and pipe) to assess the overall and spatial effects of sulfur fixation. Results indicated that fixation rates increased with increasing sulfur boiling rates. Additionally, sulfur fixation was found to occur rapidly, with most of the fixation taking place near the injection port. The study also found that the sulfur-loading capacity exceeded the stoichiometric estimates based on Ni + Fe, consistent with historical data. Further studies are needed to fully characterize these high-sulfur-loaded calcines.

The present study aims to investigate possible factors contributing to valuable metalsMetals losses, particularly nickelNickel, in slagsSlag from the nickel smeltingNickel smelting process. It involves a high-temperature phase equilibriaEquilibria study in the slagSlag systems relevant to nickel smeltingNickel smelting and industrial slagSlag sample analyses. Phase equilibriaEquilibria study defines the thermodynamic limits of the system, providing the foundation for analyzing the industrial samples. Deviations from the equilibrium help identify the potential factors restricting equilibrium leading to insights into finding the causes of metalMetals losses and recovery limitations. Quenched slagSlag samples were collected from various locations across the flash smeltingFlash smelting furnace at the Kalgoorlie Nickel SmelterNickel smelter (KNS) to analyze compositional changes in the molten slagSlag throughout the furnace. High-temperature equilibration laboratory experiments were also conducted to investigate phase equilibriaEquilibria in the “FeO”-MgO-SiO2\“FeO\”-MgO-SiO2 slagSlag system in equilibrium with Fe–Ni alloys under controlled oxygen partial pressures. Additionally, thermodynamic prediction and process modelling were performed using a thermodynamic database from the PyrometallurgyPyrometallurgy Innovation Centre (PYROSEARCH). The results indicate that nickelNickel losses in industrial samples occur through both entrainment of high-Ni matteMatte particles and the dissolutionDissolution of Ni in liquid slagSlag and olivineOlivine solid solution. Experimental findings suggest that, at constant temperature, oxygen partial pressure significantly influences nickelNickel solubilitySolubility in slagSlag and olivineOlivine solid solution. Assessing the mechanisms of nickelNickel loss provides valuable insights for optimizing smeltingSmelting conditions to enhance metalMetals recovery and improve the efficiency of industrial smeltingSmelting operations.

The two-stage thermal upgradingThermal upgrading process was developed to extract Ni in the form of ferronickelFerronickel (FeNi) concentrate from low-grade ultramaficUltramafic Ni concentrates without the need to smelt it at higher temperatures. This study explores the use of the FeNi concentrate as additional feed in a flash smeltingFlash smelting operation. Conventional flash furnace concentrate was blended with the FeNi concentrate to form a composite powder containing 10, 20, and 30% FeNi concentrate where the matteMatte generated under inert conditions were compared to the theoretical values to assess the methodology used. The flash furnace concentrate (0% FeNi), ferronickelFerronickel concentrate (100% FeNi) and 10% FeNi material were oxidized with a 3-, 7-, and 10-s oxygen blow to determine the resulting matteMatte composition under highly oxidizing conditions.

Sibanye-Stillwater’s Furnace 1 crucible design has been upgraded to improve sidewall campaign lifeCampaign life and reliability. Tenova Pyromet was awarded the contract for the engineering, supplySupply and construction for the Furnace 1 crucible upgradeUpgrade. The crucible upgradeUpgrade included a larger furnace diameter, new hearth and sidewall liningLining-cooling system designs, and new matteMatte and slagSlag tap-hole designs. A new composite copperCopper-graphiteGraphite cooler design is used to prevent sulphidation corrosionCorrosion that commonly occurs in PGMPlatinum Group Metals (PGM) smelters. The novel lower sidewall design employs a graphiteGraphite back liningLining combined with forced air cooling to remove excess heat from the working liningLining adjacent to the critical matteMatte-slagSlag tidal zone. As part of the upgradeUpgrade, the matteMatte tap-hole installation was elevated above the hearth skewback level. The paper describes the design changes and its role in improving the furnace operationFurnace operation and reliability. The upgraded furnace has been in operation since August 2022. Observations during the first matteMatte tap-hole lintel repair are presented. The furnace performance since start-up is discussed and evaluated against the objectives specified for the upgradeUpgrade project.

Hatch has been at the forefront of electric arc furnaceElectric arc furnaces (EAF) design since the early 1970s (Nelson et al. in Southern African pyrometallurgy, 2006), contributing to many high-power, high-productionProductions nickel smeltingNickel smelting furnaces currently in operation. Our long-standing clients—Glencore, South32, Anglo American, Vale, and Rio Tinto—have benefited from our advanced furnace and process technologiesTechnology for decades. In response to evolving global metalMetals market dynamics and environmentalEnvironmental challenges, we have intensified our focus on optimizing furnace campaign lifeCampaign life to reduce lifecycle costsLifecycle costs. Our Asset Performance Management (APMAsset Performance Management (APM)) Group leverages our deep furnace designFurnace design expertise to utilize operational monitoring and maintenance data, enabling clients to assess asset conditions and performance more effectively. Drawing on over 50 years of industry experience, we empower clients to make both day-to-day and long-term strategic decisions. This paper outlines our APMAsset Performance Management (APM) approachOperational and asset monitoring and presents case studies that illustrate its effectiveness.

Despite ongoing efforts to find alternative materials, cobaltCobalt remains important in the productionProductions of rechargeable batteriesBattery essential for the energy transition. Currently, most cobaltCobalt is sourced from unethical and politically unstable regions as a by-product of nickelNickel and copperCopper extractionExtraction. However, primary cobaltCobalt deposits, such as those in the Iron Creek area, could provide a reliable and responsible supplySupply of this metalMetals. In these deposits, cobaltCobalt is encapsulated within the pyritePyrite (FeS2) lattice, making traditional beneficiationBeneficiation methods ineffective. This study evaluates the potential of thermal decompositionThermal decomposition of pyritePyrite as an effective beneficiationBeneficiation strategy for cobaltiferous minerals by employing a factorial design to assess the effects of key process parameters on two concentrates from a differential flotationFlotation stage. Thermal decompositionThermal decomposition in an inert atmosphere facilitated partial desulfurization, converting pyritePyrite into lower sulfides—pyrrhotite and troilite—while increasing cobaltCobalt grades by 5–17% and producing high-purity sulfur as a valuable by-product. Subsequent magnetic separation of the calcine yielded final concentrates containing 3.0–3.5% cobaltCobalt, representing an overall improvement of 66–192% compared to previous studies. This technologyTechnology is currently patent pending.

The aim of this study is to find a procedure to recycleRecycle spent lithiumLithium-ion batteriesBattery containing lithiumLithium-cobaltCobalt oxide (LiCoO2), lithiumLithium-nickelNickel-cobaltCobalt oxide (LiNiCoO2), and/or lithiumLithium-nickelNickel-cobaltCobalt-aluminum oxide (LiNi0.8Co0.15Al0.05O) as the cathode material, without the need to useAcid recycle acidAcid and/or costly reagents and without generating hazardous liquid waste. To this end, we developed a laboratory-scale, economical and environmentally advantageous, pyrometallurgical method which is able to efficiently extract lithiumLithium as lithiumLithium carbonate (Li2CO3), while, in parallel, the heavy, non-ferrousNon-ferrous 3d transition metalsMetals are recovered in the form of ingots.

CobaltCobalt-nickelNickel separationCobalt-nickel separation isLi-ion batteries an essential process step for many hydrometallurgical flowsheetsFlowsheet. Conventionally, solvent extraction (SXSolvent Extraction (SX)) is used to selectively recover cobaltCobalt from a pregnant leach solution (PLS) containing a mixture of metalsMetals. An alternative to a traditional mixer-settlerMixer-settler (SX)Solvent Extraction (SX) equipment design is supported liquid membraneSupported liquid membranes (SLM) technologyTechnology. SLM utilizes the same basic chemistry principles as SXSolvent Extraction (SX), except extractionExtraction and stripping are carried out simultaneously across a porous membrane, which is laden with the extractant and diluent, the organic phase being supported in the membrane by wetting forces. Previous work demonstrated Co–Ni separation using SLM with 25 cm2 membranes and 300 g of feed and strip phases. The current work increased the scale to 57 m2 hollow fibre membrane modules and feed to 100 kg. The feed phase was a synthetic mixture of 10,000 ppm Co2+ and Ni2+ each as sulphates, with 0.5 M sodium acetate as buffer, while the strip phase was 50 or 100 kg of 10 or 20 wt% H2SO4. The feed pH was controlled via the addition of 2 N NaOH or KOH. The extractant was 10 wt% (approximately 0.3 M) hydrophobic phosphorus acidAcid in a non-aromatic hydrocarbon (D80, Exxon). Complete extractionExtraction of Co2+ was achieved with purities of ~ 99.5–99.8% in a single stage at more than 90% Co2+ recovery. The batch tests were repeated 5 times on a single module and replicated on a 2nd module. Co2+ mass transfer rates decreased during the first two tests, from 3.0 gmol/m2/day to 2.4 gmol/m2/day, and were 2.0 to 2.2 gmol/m2/day in the two subsequent tests.

The growing demandDemand for valuable metalsMetals from complex ores and secondary sourcesSecondary sources—such as lithiumLithium-ion batteriesBattery—highlights the urgent need for innovative extractionExtraction methods. This study addresses this challenge by optimizing a solvent extractionSolvent Extraction (SX) flowsheetFlowsheet using phosphinic, phosphonic, and phosphoric acidsPhosphoric acid—specifically IONQUEST® 290, IONQUEST® 220, andIONQUEST solvent extractants IONQUEST® 801—as extractants for the selective recovery of key metalMetals ions (manganese, cobaltCobalt, nickelNickel, and lithiumLithium) from black massBlack mass residue. The distinct chemical properties, solubilitySolubility, and interaction mechanisms of these acidsAcid with metalMetals ions are analyzed to improve extractionExtraction efficiency. The optimized flowsheetFlowsheet was developed through a series of laboratory batch experiments to identify optimal operational parameters and was subsequently validated using lab-scale counter-current experiments, demonstrating the practical applicability of the proposed method.

Hydrometallurgical treatment of black massBlack mass (produced from recyclingRecycling lithiumLithium-ion batteriesBattery) has generated significant attention in recent years as a critical step in the circular economy of batteryBattery metalsMetals. Many hydrometallurgical flowsheetFlowsheet configurations exist and are reported by recyclingRecycling companies. Typically, flowsheetsFlowsheet can be characterized by (a) complete metal separationMetal separation via solvent extractionSolvent Extraction (SX), electrowinning and/or crystallizationCrystallization operations and (b) productionProductions of a mixed hydroxide or batteryBattery precursor material. This paper will provide an updated review of some of the flowsheetsFlowsheet considered by current companies, evaluate current challenges faced in the implementation of these processes and provide insight into how to derisk such processes from the perspective of a commercial metallurgical testingTesting laboratory.

ElectrodialysisElectrodialysis is an emerging technique for sustainable nickelNickel refining in recyclingRecycling of black massBlack mass from spent lithiumLithium-ion batteriesBattery. Black massBlack mass is leached and the leachate is mixed with a chelating agentChelating agents to form nickelNickel chelates, recoverable by electrodialysisElectrodialysis. Two agents were used for recovering nickelNickel from NMCNickel-Manganese-Cobalt (NMC) 811 type black massBlack massethylenediaminetetraacetic acidAcid (EDTA)Ethylenediaminetetraacetic Acid (EDTA) and hydroxyethylethylenediaminetriacetic acidAcid (HEDTA)Hydroxyethylethylenediaminetriacetic Acid (HEDTA), EDTA being a stronger chelating agentChelating agents but HEDTAHydroxyethylethylenediaminetriacetic Acid (HEDTA) being more selective towards nickelNickel. EDTA and HEDTA gave recoveries of 99.2% and 98.5%, respectively, with 82.6% and 33.3% co-recovery of cobaltCobalt at 10% excess addition of the chelating agentChelating agents. Smaller additions gave recovery losses but selectivity improvements, with only 4.15% and 4.64% co-recovery of cobaltCobalt using EDTA and HEDTA at 80% of stoichiometric addition. 87.8% of EDTA was selectively recovered by acidic precipitationPrecipitation at pH 0.3, later recovering 92.9% of nickelNickel by precipitationPrecipitation at pH 12. HEDTA could not be recovered by this method and had to be decomposed with thermally activated persulfate resulting in 96.2% recovery of nickelNickel. This also worked for EDTA, precipitating 96.0% of nickelNickel. EDTA is the preferred chelating agentChelating agents owing to its similar performance to HEDTAHydroxyethylethylenediaminetriacetic Acid (HEDTA) at stoichiometric addition and its potential to be recirculated in an industrial process.

Rapid growth of the electric vehicleElectric Vehicles (EVs) and energy storage system industries has significantly increased the demandDemand for lithium ion batteriesLithium Ion Batteries (LIB) and the generation of end-of-life lithium ion batteriesLithium Ion Batteries (LIB) (EOL LIBs). This trend highlights the importance of recyclingRecycling EOL LIBsLithium Ion Batteries (LIB). Currently, EOL LIBs are generally processed through hydrometallurgical methods. The conventional lixiviants used in leachingLeaching processes are inorganic acidsAcid, which may release environmentally harmful substances such as Cl−, NOx, Na2SO4, and total nitrogen. Therefore, this research aims to enhance the environmentalEnvironmental sustainabilitySustainability of the leachingLeaching process by using an alternative lixiviantAlternative lixiviant, methanesulfonic acid (MSAMethanesulfonic Acid (MSA)). BioleachingBioleaching using indigenous species in Korea was also investigated. Various concentrations of MSAMethanesulfonic Acid (MSA) and hydrogen peroxide (H2O2) were tested between 25 and 80 ℃. Meanwhile, clean nickelNickel, cobaltCobalt, manganese (NCM) cathodic materials were leached using thirty new strains from abandoned mine sites in Korea to determine the best bioleachingBioleaching strain. LeachingLeaching of black massBlack mass with MSAMethanesulfonic Acid (MSA) had higher leachingLeaching efficiencies than H2SO4 for both Co and Ni. It achieved leachingLeaching efficiencies over 97% with 1.0 M MSAMethanesulfonic Acid (MSA) and 1.5 M H2O2 at 80 ℃. Activation energy of Co and Ni were 1.9 and 62 kJ/mol, which means different leachingLeaching mechanism by metalsMetals. Finally, conventional solvent extractionSolvent Extraction (SX) can be applicable to extract > 99% Co from Ni and Co methanesulfonate leachate by Cyanex 272. Meanwhile, the indigenous strain of Acidithiobacillus ferriphillus 9-P1 showed the highest leachingLeaching efficiency among all strains tested, achieving above 99% metalMetals leachingLeaching efficiency within 24 h. However, the leachingLeaching efficiencies of Li 82%, Ni 81%, Mn 83%, and Co 84% from NCM black massNCM black mass within 24 h indicated the possibility of toxic effects from the constituents of black massBlack mass. This study highlights the potential of alternative leachingLeaching systems on hydrometallurgical processesHydrometallurgical processes to enhance environmental sustainabilitySustainability.

NickelNickel (Ni)-based superalloys are widely used in aerospace due to their exceptional resistance to heat and corrosionCorrosion. However, these properties also pose significant challenges for recyclingRecycling. This study uses liquid metal dealloyingLiquid metal dealloying (LMD) to disrupt the superalloy structure by selectively dissolving Ni from spent Ni-based superalloys using magnesiumMagnesium (Mg). A crucible was designed to facilitate Mg recyclingRecycling. The Ni-based superalloy (GH3128) was treated with varying Mg to superalloy mass ratios. The residual superalloy was separated from reacted Mg via vacuum distillation, achieving Mg regeneration above 90% and Ni extractionNi extraction of 81%. The yield strength of the residual superalloy decreased to 289.6 MPa, accompanied by the formation of a porous structure. Additionally, the LMD process is applicable to other superalloy grades, including Inconel 718 and DD5. The method provides important support for the recyclingRecycling and sustainable developmentDevelopment of Ni resources.

The expected large growth in electric mobility is an opportunity for the whole batteryBattery value chain, but also poses challenges, such as requiring a very large amount of critical raw materials, with nickelNickel, cobaltCobalt, and lithiumLithium in particular. Over the next decade, increasingly larger amounts of batteriesBattery from electric vehiclesElectric Vehicles (EVs) will reach their end-of-life and significant amounts of productionProductions scraps from batteryBattery manufacturing will be generated. In order to close the loop, developmentDevelopment and industrialization of sustainable battery recyclingBattery recycling flowsheetsFlowsheet is key, so that both productionProductions scrap and end-of-life batteriesBattery can be recycled back to “batteryBattery grade” intermediate products and reduce the need for additional critical raw materials. Standalone battery recyclingBattery recycling flowsheetsFlowsheet are typically categorized in two routes: (1) “pyro-hydro”, a combination of batteryBattery smeltingSmelting in a pyrometallurgical process, followed by further refining of the alloy through hydrometallurgyHydrometallurgy; and (2) “full-hydro”, a combination of (thermo)mechanical pretreatment and further hydrometallurgical refining of the resulting black massBlack mass. We present a technical comparison between both routes and illustrate how the added complexity of a smeltingSmelting operation in the “pyro-hydro” route has the potential to simplify downstream hydrometallurgical refining compared to the “full-hydro” route. We will show how expectations and specifications for “batteryBattery grade” intermediate products are an important parameter when assessing strengths and weaknesses of both routes.

There is limited information regarding the environmentalEnvironmental impacts associated with the battery recyclingBattery recycling processes aiming to recycleRecycle cathode materials. Process simulationProcess simulation is a powerful tool that, when databases are not available, can generate appropriate system estimates that allow topical knowledge gaps to be addressed. In this study, a life cycle inventory was obtained through process simulation, to assess the life cycle assessment (LCA)Life Cycle Assessment (LCA) of an emerging hydrometallurgyHydrometallurgy battery recyclingBattery recycling. Three scenarios were assessed: (a) exclusion of the organic solvent extractionExtraction (SX)Solvent Extraction (SX) chemicals, (b) based on a generic database, and (c) from the literature database. It was observed that the highest impact categories for the organics LCA were global warming (GW), energy resources: non-renewable, (ERf) and eutrophication: freshwater (EThf). The results showed that SX organics must always be included while conducting a LCA for recyclingRecycling and primary ore mining. Generating a higher environmental burden than the environmental impacts of virgin materials; GW (+ 50%), ERf (+ 100%), and EThf (+ 60%). Although there is some uncertainty related to the findings, nevertheless, the results are the first approach to predict the environmentalEnvironmental impacts of an industrial-scale battery recycling process already during the laboratory research stage.

MethanesulfonicLithium-ion batteries acid (MSAMethanesulfonic Acid (MSA)) is gaining attention as promising lixiviant in hydrometallurgical processesHydrometallurgical processes. In this study, MSAMethanesulfonic Acid (MSA) was utilized to recover critical metalsCritical metals (lithiumLithium, nickelNickel, cobaltCobalt, and manganese) from the black massBlack mass of spent lithiumLithium-ion batteriesBattery. The effects of leachingLeaching parameters were examined and optimized. Complete leachingLeaching of all target metalsMetals was accomplished under the conditions: 500 rpm, 1.5 M MSAMethanesulfonic Acid (MSA), 0.2 M H2O2, 60 °C, and 50 g/L, for 4 h leachingLeaching. The leachingLeaching kinetics were studied using the Avrami model, showing that the leachingLeaching was governed by chemical reactions, with activation energies of 46.81 kJ/mol for Li, 58.9 kJ/mol for Ni, 59.67 kJ/mol for Co, and 58.6 kJ/mol for Mn (25 − 70 °C). The graphiteGraphite content in the leachingLeaching residue was improved through pyrolysis.

The increasing global demandDemand for lithiumLithium-ion batteriesBattery, driven by the rise of portable devices and electric vehiclesElectric Vehicles (EVs), has prompted a surge in the need for efficient battery recyclingBattery recycling processes. However, the rising demandDemand for raw materials such as nickelNickel, cobaltCobalt, and lithiumLithium highlights the importance of improving recyclingRecycling processes. Among various recyclingRecycling techniques, hydrometallurgical processesHydrometallurgical processes, particularly solvent extractionSolvent Extraction (SX), are vital for producing high-purity products. These processes, though effective, are energy-intensive, costly, and reliant on empirical methods. To enhance process efficiency in terms of productivity and quality reliability, this study investigates the use of numerical analysisNumerical analysis and system developmentDevelopment. By developing an in-house code, the study aims to optimize the solvent extractionSolvent Extraction (SX) process by predicting the number of stages, flow rates, and mixer volume, and calculating the concentration per stage. This approach provides crucial insights into process design and material balance for each stage, contributing to a more efficient and cost-effective battery recyclingBattery recycling process.

Recent circular economic initiatives have driven the widespread use of lithiumLithium-ion batteriesBattery (LIBsLithium Ion Batteries (LIB)) in consumer electronics, electric vehiclesElectric Vehicles (EVs), and renewable energy storage. End-of-life LIBsLithium Ion Batteries (LIB) contain critical elements, making LIB recyclingRecycling a promising strategy to reduce mining demandsDemand, hazardous waste, and landfill metalsMetals. However, conventional recyclingRecycling methods rely on inorganic acidsAcid and organic solvents, which pose significant environmentalEnvironmental risks. Deep eutectic solventsDeep eutectic solvents (DESs) have emerged as sustainable alternatives. They are mixtures of hydrogen-bond donors and acceptors held together by hydrogen bonding, resulting in thermally and chemically stable, non-flammable, biodegradable, and low-volatility properties. DESs can dissolve metal oxidesMetal oxides without oxidizing or reducing chemicals, making them suitable for LIB recyclingRecycling. Though promising, the application of DESs in LIB recyclingRecycling is relatively new, and fundamental solubilitySolubility data for metal oxidesMetal oxides in these solvents are limited. In this work, we investigate the solubilitiesSolubility of lithiumLithium, nickelNickel, and cobaltCobalt oxides in DESs. Three binary DESs are synthesized and analyzed to determine their density, viscosity, and thermal stability. The solubilitiesSolubility of Li2O, NiO, Ni2O3, CoO, and Co3O4 in these DESs are then evaluated at various temperatures. These results suggest that DESs may selectively dissolve metal oxidesMetal oxides, improving LIB recyclingRecycling efficiency and selectivity.

With the rise of electric vehiclesElectric Vehicles (EVs), lithiumLithium-ion batteryBattery (LIBLithium Ion Batteries (LIB)) recyclingRecycling needs to increase to meet the economic demandsDemand of LIBsLithium Ion Batteries (LIB) and the environmentalEnvironmental concerns of “black massBlack mass” (BM). Research focused on using magnetic processingProcessing to separate the lithiumLithium metal oxideMetal oxides (LMO) cathode materials from the BM to determine viability and benefits for downstream hydrometallurgical processesHydrometallurgical processes. Magnetic separation was successful in the enrichment of LMOs, with a lithiumLithium concentrate forming in the process water that can be processed separately.

The growing demandDemand for lithiumLithium-ion batteriesBattery (LIBsLithium Ion Batteries (LIB)) for the electronic, automobile industries and energy storage combined with the limited natural resources of key elements on earth, in particular nickelNickel and cobaltCobalt, drives the need of efficient recovery these elements from spent LIBsLithium Ion Batteries (LIB). In this article, a comprehensive review of nickelNickel and cobaltCobalt recyclingRecycling technologiesTechnology from spent and scraps of LIBsLithium Ion Batteries (LIB), including hydrometallurgyHydrometallurgy and pyrometallurgyPyrometallurgy, and emerging approaches such as direct recyclingDirect recycling, biometallurgyBiometallurgy, electrochemistryElectrochemistry, and solvometallurgy were conducted. While conventional recyclingRecycling methods present environmental and efficiency challenges, direct recyclingDirect recycling, electrochemistryElectrochemistry, biometallurgyBiometallurgy, and solvometallurgySolvometallurgy show considerable promise in reducing energy consumption, minimizing the environmental impacts and attaining circular economy in LIB recyclingRecycling industry. Vigorous efforts are required to showcase the scalability, reliability, cost-effectiveness, and sustainabilitySustainability of emerging technologiesTechnology before commercialization.