Rare Metal Technology 2021

The widespread and increasing use of Li-ionLithium-ion batteriesLithium-Ion Batteries (LIBs) has led to an impending need for recyclingRecycling solutions. Consequently, recyclingRecycling ofLithium-Ion Batteries (LIBs) spent Li-ionLithium-ion batteriesLi-ion battery recycling with energy-efficient, environmentally sustainable strategies has become a research hotspot. In this work, eutectic freezeEutectic freeze crystallization crystallizationCrystallization (EFC), which requires less energy input than conventional evaporative crystallizationCrystallization (EC), has been investigated as a methodMethods for the recoveryRecovery of Ni and Co sulfates from synthetic acidic strip solution in the recyclingRecycling of NMC or NCA Li-ionLithium-ion batteriesLithium-Ion Batteries (LIBs). Two binary sulfate systems have been studied. Batch EFC experiments have been conducted. It is shown that, with suitable control of supersaturation, ice and salt crystals can be recovered as separate phases below the eutectic temperatures. The work shows that EFC is a promising alternative to EC for the recoveryRecovery of Ni and Co sulfates from spent Li-ionLithium-ion batteriesLithium-Ion Batteries (LIBs).

A novel electrochemical separation process was developed to recover lithiumLithium (Li) from an end-of-lifeLithium (Li) lithium-ionLithium-ion batteryLithium-Ion Batteries (LIBs) of an electric vehicle using an environmentally friendly and cost-effective process based on electrodialysisElectrodialysis. LithiumLithium (Li), nickel, manganese, and cobaltCobalt were first extracted from the cathode activeMaterials materialCathode active material of a spent lithium-ionLithium-ion batteryLithium-Ion Batteries (LIBs) through a hydrometallurgical leachingLeaching process using H2SO4H2SO4+H2O2 leachant under the optimal operating conditions. After leachingLeaching, nickel, manganese, and cobaltCobalt were recovered as complex anions coupled with ethylenediaminetetraacetic acid chelating agent, whereas lithiumLithium (Li) was recovered as lithiumLithium (Li) hydroxide using electrodialysisElectrodialysis. The results showed that almost 100% of lithiumLithium (Li) was separated from nickel, manganese, and cobaltCobalt. Future work is underway to improve and optimize the separation process.

Layered H2TiO3 has shown to be a promising selective lithiumLithium (Li) adsorbent to extractExtract lithium from brine solutions. Despite the promising performance of these materialsMaterials, the lithiumLithium (Li) adsorption mechanism of layered H2TiO3 is still not properly understood. It is currently accepted that lithiumLithium (Li) adsorption takes place via Li+-H+ ion-exchange reaction without involving any breakage of chemical bonds. However, in this study we show that Li+-H+ ion exchange involves the breaking of surface O–H bonds present in the HTi2 layers along with the formation of O-Li bonds. Using FTIR and Raman spectroscopy, we also show that the isolated surface hydroxylsSurface hydroxyls are actively involved in lithiumLithium (Li) ion exchangeIon-exchange compared to hydrogen-bonded surface hydroxyl groups, which are present in the interlayer spacings. This newly proposed mechanism also explains the lower observed adsorption capacity from theoretical values.

At present, the global production of 45,000 tons of lithiumLithium (Li) is obtained by molten saltMolten salts electrolysis using lithiumLithium (Li) chloride as a rawRaw materials materialMaterials. Due to the release of chlorine gas in the production process, the environment is seriously polluted and the energy consumption is high. In this paper, lithiumLithium (Li) carbonateLithium carbonate is used as a rawRaw materials materialMaterials, and aluminum powderAluminum metal powder is used as a reducing agent to extractExtract metal lithiumLithium (Li) in a vacuum reduction furnaceVacuum reduction furnace by aluminothermicAluminothermic reductionAluminothermic reduction. The lithiumLithium (Li) recoveryRecovery rate is 85% and the purity of metal lithiumLithium (Li) reaches 99.5%. In the laboratory, a continuous vacuum lithiumLithium (Li) reduction furnace was developed. No harmful gases were released during the entire production process. It was environmentally friendly. The production of lithiumLithium (Li) by aluminothermicAluminothermic reductionAluminothermic reduction is a very promising methodMethods. The continuous lithiumLithium (Li) vacuum reduction furnaceVacuum reduction furnace is the key equipment of this process, which lays the foundation for future industrial applicationIndustrial applications.

With high specific capacity, high nominal voltage, low self-discharge, and low cost, layered LiNixMnCo1-x-yO2LiNixMnCo1-x-yO2cathode (NMC) cathode has gained interest for second-generationLithium (Li) lithium-ionLithium-ion batteriesLithium-Ion Batteries (LIBs). Because the performance of Li-ionLithium-ion batteriesLithium-Ion Batteries (LIBs) highly depends on the composition, crystallography, morphology, and other parameters decided during synthesis, interest in developing high-performance Li-ionLithium-ion batteriesLithium-Ion Batteries (LIBs) has motivated researchers to develop novel synthesis methodsMethods to control these parameters. Although significant progress has been made in several synthesis methodsMethods such as sol–gel, hydrothermal, solid-stateSolid-state reaction, and emulsion drying at lab scale, an industrially viable synthesis approach is needed for the cost-effective production of highly efficient NMC cathode materialsMaterials. This paper summarises the common synthesis methodsMethods investigated at laboratory and industrial scales for new and regenerated NMC cathode from end-of-life Li-ionLithium-ion batteriesLithium-Ion Batteries (LIBs) and their effect on the battery performance. It is found that co-precipitationCo-precipitation is the most commonly used methodMethods to produce NMC cathode, while spray pyrolysisSpray pyrolysis is commonly used at the industrial scale.

CobaltCobalt, an exceptional cathode materialMaterials present inLithium (Li) lithium-ion batteries (LIBs)Lithium-Ion Batteries (LIBs), is an essential element for the production of energy storage devices. But, the lifespan of rechargeable batteries is decreasing day-by-day, which become obsolete after reaching their end of life. Therefore, an enormous amount of discarded LIBsLithium-Ion Batteries (LIBs) are generated. Keeping in mind the above, a novel approach has been made to selectively recover cobaltCobalt from sulfate leach liquorLeach liquor of discarded LIBsLithium-Ion Batteries (LIBs) containing 1.4 g/L Cu, 1.1 g/L Ni, 11.9 g/L Co, 6.9 g/L Mn, and 1.2 g/L Li. Initially, Cu and Ni were extracted by solvent extraction techniques using 10% LIX 84-IC. Almost complete precipitationPrecipitation of cobaltCobalt occurred from leach liquorLeach liquor at pH ~3 using ammonium sulfide solutions. CobaltCobalt from the precipitated product was further dissolved in H2SO4H2SO4 in presence of H2O2 at elevated temperature. The leach liquorLeach liquor obtained was evaporated to get the cobaltCobalt sulfate with a purity of more than 98%.

The current study investigates the energy consumption and the corresponding global warming potential (GWP) of telluriumTellurium recoveryRecovery from multimetal solution by the use of a tailored electrochemical recoveryRecovery approach based on electrodeposition-redox replacement (EDRR). A three-electrode cell was used to recover Te from synthetically prepared pregnant leach solution similar to the PLS of leached Doré slagSlag (30% aqua regia, [Cu] = 3.9 g/L, [Bi] = 4.6 g/L, [Fe] = 1.4 g/L, and [Te] = 100–500 ppm). The enrichment of Te on the electrode (with 100 EDRR cycles) had a calculated global warming potential of 3.7 CO2 -eqv from a solution with 500 ppm Te based on a Finnish energy mix. In comparison, a decrease of Te concentration to 100 ppm increased the corresponding environmental impact to 16.9 CO2 -eqv. Overall, GWP was shown to be highly dependent on the geographical area, i.e. the dominating energy production methodsMethods.

A new methodMethods of making sodium metalSodium metal from sodium sulfateSodium sulfate is discussed. Anhydrous sodium sulfateSodium sulfate as may be made from sodium sulfateSodium sulfate waste solutions is reduced with aluminum metal. The reactor designReactor design to make sodium metalSodium metal along with aluminum and sulfur oxides minimizing wastes is explored. Thermochemical tools are used in this development. Experiments carried out in this regard and how they fit the thermochemistryThermochemistry are evaluated in this paper.

The increasing demand for pure tungsten and its compounds due to their high tensile strength makes them a versatile materialMaterials in catalyst, heavy alloy, cemented carbide, among others. This exceptional property makes it to be of high interest by industrialists for use in the engineering and manufacturing industries. Thus, preparation of ammonium metatungstate (AMT)Ammonium Metatungstate (AMT) from a Nigerian wolframiteWolframite ore by hydrometallurgical technique was examined in sulphuric and phosphoric acid. During leachingLeaching, parameters such as leachant concentration, reaction temperature, and particle size on ore dissolution were examined. At optimal conditions (2.0M H2SO4H2SO4 + 0.15M H3PO4H3PO4, 75 °C, −63 µm), 93.7% of the ore dissolved within 120 min. The calculated activation energy of 6.93 kJ/mol supported the proposed diffusion mechanism. The leachate at optimal conditions was treated to obtain a pure tungstate solution. The purified solution was beneficiated to prepare a high grade AMTAmmonium Metatungstate (AMT) ((NH4)6[H2W12O40]·4H2O: 96-901-3322, m.p.: 98.7 °C, density: 2.16 g/cm3), which serves as an intermediate for some defined industries.

Various e-wastesE-waste like waste LCD, LED, and LCD etching industry wastewaterWastewater are important secondary resourcesSecondary resources for indiumIndium, which is a critical metal. In this research, the industrial-scale indiumIndium recoveryRecovery from e-wasteE-waste resources like waste LCD, LED, and LCD industry etching wastewaterWastewater is being emphasized through simulation and integration of the developed processes. A demonstration plant for indiumIndium recoveryRecovery on one ton/day of ITO etchingITO etching wastewaterWastewater has been developed with almost complete (99%) recoveryRecovery of indiumIndium. For the indiumIndium recoveryRecovery, integration of the processes can be managed by following two approaches unique to this system, (i) utilization of ITO etchingITO etching industry wastewatersWastewater for the leachingLeaching of waste LCD, (ii) integration of leachingLeaching processes developed for waste LCD and LED with that of the treatment process for ITO wastewatersWastewater. Through the proposed approach, the semiconductor manufacturing industry and ITO industry can address various pressing issues like (i) waste disposal, (ii) indiumIndium recoveryRecovery, (iii) circular economyCircular economy.

To cope up with the supply–demand gap of lithiumLithium (Li) (Li) an essential energy element, the recyclingRecycling of waste industrial effluent (generated after cobaltCobalt recyclingRecycling from wasteLithium-Ion Batteries (LIBs) Li-ionLithium-ion batteriesLi-ion battery recycling) is targeted. In industry, after the recoveryRecovery of Co, Cu, Ni, and graphite from one ton of black cathodic materialMaterials of Li-ionLithium-ion batteries Lithium-Ion Batteries (LIBs) about 8 m3 of waste effluent containing 5–10 g/L Mn and 1–3 g/L Li is generated. Systematic precipitationPrecipitation studies were carried out using saturated alkaline solution varying Eh/ pH of the effluent. Settling time 30 min and pH ~12 were found to be optimum conditions for maximum precipitationPrecipitation of Li (~90%) as salt. PrecipitationPrecipitation studies for Mn/ Li with scientific validation were also carried out and discussed. The process developed has tremendous potential to be commercialized in industry after scale-up studies.

The extraction of platinum group metals (PGM)Platinum-Group Metals (PGM) contained in waste automobile catalyst monolithic honeycomb was investigated by a novel approach that combines a pyro-metallurgicalPyro-metallurgy and electrolysis step. The first step aims to both up-concentrate the amount of PGMsPlatinum-Group Metals (PGM) by using a metal collector, as well as to prepare the conductive materialMaterials to be used as anode in the electrolysis step. The electrolysis step is carried out in a molten chloride electrolyte, where the PGMsPlatinum-Group Metals (PGM) remain as metallic residue, and the refined metal is further reused in the pyro-metallurgicalPyro-metallurgy step. Optimization of the pyro-metallurgicalPyro-metallurgy process led to 82–100% metal recoveryRecovery rates, while the PGMPlatinum-Group Metals (PGM) recoveryRecovery rates were close to 100%. Furthermore, the electrolyte composition and working temperature, as well as cell design of the subsequent electrolytic methodMethods, were adjusted. The process was assessed in a lab-scale electrolysis reactor, where PGMsPlatinum-Group Metals (PGM) could be extracted selectively at a current efficiency of around 70%.

Due to the supply gap towards increasing demand as well as loss of precious metalsPrecious metals by illegal recyclingRecycling, present research reports application-oriented processes developed at CSIR-NML, India to recover precious metalsPrecious metals from small components of e-wasteE-waste containing ~0.1–0.8% Ag, ~0.03–0.9% Au, ~0.01–0.02% Pd, ~0.0003–0.0005% Pt, and related effluent. Firstly, ~99.99% Au was recovered from plated e-wasteE-waste using the process of selective leachingLeaching followed by charcoal adsorption and heat treatment, whereas the second process consists of dismantling, physical/ chemical pre-treatment ofPre-treatment of e-waste e-wasteChemical pre-treatment of e-waste followed by hydrometallurgical processing to recover 99% Ag, 99.9% Au, 95% Pd, and 90% Pt. Apart from the above, leachingLeaching and selective precipitationPrecipitation were used to recover ~95% Ag from waste computer keyboards. The effluent generated during the e-wasteE-waste processing was found to contain ~8–10 mg/L Au, which was also recovered using ion-exchangeIon-exchange technique. All processes presented are scientifically validated and commercially viable after scale-up studies.

Interest in the recoveryRecovery of Rare EarthRare earths ElementsRare earth elements (REEs) has increased significantly in the last few years. There has been a concomitant increase in research and in process developmentProcess development for REE recoveryRecovery [1]. Antisolvent crystallizationCrystallization has the potential to recover REE from solution at high yields and with minimal waste. However, antisolvent addition generally results in uncontrolled primary nucleation and very small product crystals. A better approach could be to carry out the crystallizationCrystallization in fluidized bed reactors. Therefore, our approach in this work was to focus on the development of a novel process for the recoveryRecovery of REE by combining antisolvent crystallizationCrystallization and a fluidised bed process. Thermodynamic modellingThermodynamic modelling showed that, when ethanol is added to a Nd2(SO4)3 or Dy2(SO4)3 solution as an antisolvent, the only solid products formed were the REE sulphate salts. Since the solubilities of the REE sulphate salts at any of the Organic/Aqueous (O/A) ratios are of similar orders of magnitude to those of salts that have been successfully recovered in a fluidised reactor process, an antisolvent, fluidised reactor process is potentially suitable for REE sulphate salts. Batch experimentsBatch experiment showed that the yields are sufficiently high for a viable process. At the same time, the micrographs show that the nature of the formed crystals are such that they are likely to form uniform and robust coatings on seed particles in and fluidised bed reactor Fluidised Bed Reactor process. Therefore, our preliminary conclusion is that this REE system is well suited for further investigation in a combined antisolvent crystallizationCrystallization and fluidised bed process.

RecyclingRecycling electronic scrap is a significant source of rare earthRare earths metalsRare earth metals. Whereas traditional recyclingRecycling routes for some electronic scrap emphasize the recoveryRecovery of silver and goldAu, value can be attained by recovering of rare earthRare earths elementsRare earth elements from unique feed streams. This paper describes a hydrometallurgical process for the recoveryRecovery of rare earthRare earths elementsRare earth elements from hard disk drives using HCl as a re-usable extraction medium. The mixture was selectively leached using HCl to remove the magnetMagnets alloy coating from shredded hard disk drives. The dissolved rare earthRare earths elementsRare earth elements were precipitated using sodium sulfateSodium sulfate, recovered as the sodium double salt, and subsequentially converted to hydroxides. The recoveryRecovery of rare earthRare earths elementsRare earth elements is consistent with amounts predicted using a thermodynamic model based on the MSE (Mixed-Solvent Electrolyte) framework of precipitated double salts. The effect of HCl concentration was measured upon the magnetMagnets dissolution rate. In addition, the leachingLeaching rates for steel were evaluated and found to be three orders of magnitude lower than the magnetMagnets alloy. An automated system was used to control leachate pH. The magnetMagnets and steel dissolution rate were examined for various HCl concentrations. The recoveryRecovery of rare earth hydroxides was over 80%.

Developing efficient and viable processes for separation of critical metals is essential to meet the increasing demand. Rare earthRare earths elementsRare earth elements (REEs) are identified by the EU as critical resources, and moreover, they are difficult to separate due to their similar properties. Extraction chromatographyChromatography is a powerful methodMethods suitable for difficult, high-purity separations, which could form part of a separation process for recoveryRecovery of REEs from various sources. In the present work, separation of REEs from synthetic apatite leach solutions is investigated using physically immobilized extractants. By means of reverse-phase columns, reversibly functionalized by acidic organophosphorus compounds, the metals are separated by elution with nitric acid solution.

Rare-earth metals, such as La(III), Nd(III), Eu(III), or Y(III), which are recycled from electronic waste in urban miningUrban mining, can be separated and purified utilizing reactive extractionReactive extraction. Process developmentProcess development and equipment design then aim to determine the optimal reactive extractant, diluent, any additional components, equipment type, structure of the equipment internals, as well as all process parameters. This requires a deep understanding of the chemistry of the underlying complexing reactions as well as engineering expertise on extraction-process developmentProcess development as well as equipment design. To aid this design task, a tool was developed based on cascaded option trees,Option trees which combines the expertise from both sciences. Process designProcess design is supported by a prototypic workflow and by systematically structured and quantitative information on the underlying thermodynamics. The methodMethods is also applicable for extraction of diluted components from aqueous solutions, as encountered in fermentation broth in the context of bioeconomy. The methodMethods will be presented and applied to examples from urban miningUrban mining.

RawRaw materials materialsMaterials (RM) are crucial for maintaining our standard of living internationally. The fourth industrial revolution and the energy transition are reliant on access to various RMs. High-tech RMs are usually extracted as by-products from ore deposits. To increase the production of rare high-tech RM, it is essential to modify the existing bulk RM production processes and utilize partial, secondary, or waste streams. This study aims to present and discuss the necessities of redefining the concept and scope in mineral processingMineral processing and extractive metallurgyExtractive metallurgy approaches in order to secure a sustainable supply of high-tech and critical rawRaw materials materialMaterials (CRM)Critical raw materials for the economy in modern society. We introduce a list of paths and trends for developing future concepts and methodsMethods in mineral processingMineral processing and extractive metallurgyExtractive metallurgy in pursuit of the sustainabilitySustainability of high-tech CRMsHigh-tech CRMs from all resources.

Successful management of secondary waste resources is essential for the viable circular economyCircular economy. E-wasteE-waste could serve as the potential urban miningUrban mining source for the alternative supply chain of critical metals such as rare earthRare earths elementsRare earth elements (REEs). The hydrometallurgical processes for REEs are mainly designed for primary mining. Conventional approaches lack sustainabilitySustainability and the economic- and value chain-based aspects that are significant in the current era with its increasing focus and pressure to reduce environmental impact. We have performed thermodynamic calculations to simulate the solution chemistry behaviour of REEs, such as Neodymium (Nd), Dysprosium (Dy), and Praseodymium (Pr) present in NdFeB magnetsMagnets. The results suggested that one could exploit the different solubility of these REE hydroxides by controlling the pH value and separating the REEs further using extractive processes. In contrast to primary mining, the use of appropriate wet chemistry, extractive conditions with selective ligands and supported liquid membrane methodsMethods with secondary (urban) mining could open up more sustainable and economic recyclingRecycling of rare earthRare earths magnetsMagnets with reduced environmental impact and direct scalability.

The present paper reports several application-oriented processes developed for the recoveryRecovery of various non-ferrous (Cu, Ni, Al, Pb, Sn), rare (Li, Co, In), precious (Au, Ag, Pt, and Pd), and rare earthRare earths metalsRare earth metals (Nd, Ce, La, Y, Eu) from various urban ores, i.e., waste electrical and electronic equipments (WEEE), liquid crystal displays (LCD), batteries, magnetsMagnets, fluorescent tubes, etc. Initially, the WEEE and various wastes were classified and dismantled. Further, the materialsMaterials were pretreated to separate plastics, epoxy, ceramics, rubber, iron cover, and metallic concentrates. Based on their properties, plastic, epoxy and rubber could be either pyrolysed for production of marketable low-density oil and saleable activated carbon or directly recycled. The pre-treated metallic concentrates were processed by hydrometallurgical techniques, i.e., leachingLeaching, solvent extraction, ion-exchangeIon-exchange, electro-winning for maximum recoveryRecovery of metals. Various flow sheets discussed for rare metalRare metals extraction and processing strictly comply with environmental regulations.

Rare earthRare earths elementsRare earth elements (REE) are moderately abundant and are presently extracted from limited resources of monazite, bastnaesite, and loparite minerals and ionic clays. Other potential sources include large coal resources in active coal mines and existing coal waste dumps. A technology has been proposed and demonstrated that can be used to deliver clean coal for the market as well as REE-bearing non-coal materialMaterials that is concentrated in REE content and suitably sized for heapLeaching leachingHeap leaching. Additionally, a separate stream of concentrated sulfide minerals can be produced from mid to high sulfur coals suitable for the bio-oxidation production of a lixiviant suitable for leachingLeaching REE from the non-coal rock in a heap leach setting. The removal of the sulfide minerals cleans the coal, accelerates subsequent REE extraction, and eliminates the future potential for acid-rock drainage. For cost-effective enhanced leachingLeaching, bio-oxidation has been used that has been applied to coal-based materialsMaterials. During bioleachingBioleaching, Fe3+ ions generated from bioleachingBioleaching oxidize sulfide minerals such as pyrite, and subsequent production of acid. These two species (acid and Fe3+ ions) are key drivers for REEs dissolution, as well as residual sulfides removal, thereby controlling future acid mine drainage and related liabilities. This paper discusses some associated results acquired for the proposed process.

This work presents the results of scandiumScandium extraction from Greek Bauxite ResidueBauxite residue (BR) using sulfuric acid as the leachingLeaching agent and a composite extractant-enhanced ion-exchangeIon-exchange resin for a new novel, selective-ion recoveryRecovery (SIR)Selective-Ion Recovery (SIR) process developed by II–VI. The BRBauxite residue produced in Mytilineos’s plant contains approximately 75–130 mg/kg of Sc and given the plant’s current production capacity, more than 100 t of Sc are discarded each year within the BRBauxite residue stream. The optimum conditions for selective Sc extraction from BRBauxite residue were determined at lab scale in conjunction with the efficiency in Sc uptake by the resin. Under the SCALE research project, a BRBauxite residue leachingLeaching pilot plantPilot plant (Mytilineos) and Sc extraction pilot plantPilot plant (II–VI) have been established and operated in Mytilineos’s plant to demonstrate this process.

Scandium (Sc) Scandium is one of the key elements in the green economy due to its use in fuel cells and as alloying metal for aluminium, but the scandium Scandium market is not working in the sense that very little is offered at a high price making it impossible to gain use of the metal. Scandium Scandium is a rare earth Rare earths element Rare earth elements (REE) and as such, it is not very rare, but the concentration of it is always low making it a challenge to produce scandium Scandium at low cost. Compared with the other REE, Sc3+ is a much smaller ion giving it properties closer to Al3+, Fe3+, and Zr4+. We therefore often do not find Sc together with the other REE, but instead in titanium-, aluminium-, and zirconium-containing minerals. Processes involving Sc separation are different from the usual REE processes. Exploitation of the mineral davidite is used as an example of small deposits, which may be utilized through efficient mining whereas other large operations like recovery Recovery from bauxite residues Bauxite residue (red mud) Red mud are considered for comparison.

PureChromate compound chromate is an important rawRaw materials materialMaterials used extensively in chemical and metallurgical operations. Considering these uses, the oxidizing roasting processRoasting process of an indigenousIndigenous chromiteChromite ore to prepare industrial sodium chromate was investigated in this study. The effects of sodium carbonate to chromiteChromite mole ratio, reaction temperature, contact time and its thermodynamics-cum-kinetics behaviour were also discussed. The results showed that the reaction mechanism was greatly influenced as the temperature varies. A two-stage recoveryRecovery process was found favorable for the conversion methodMethods and chromate conversion rate of 97.06% with minimal residual pollutants was achieved at optimal conditions. The residual products containing iron as characterized could be easily recovered to produce sponge iron, leading to complete detoxification and zero emission of chromium residue for defined industrial applicationsIndustrial applications.

The adopted strategy and the results achieved by the Italian National Research CouncilItalian National Research Council, The within the Knowledge and Innovation Community “RawRaw materials MaterialsMaterials” of the European Institute of Innovation and Technology (KIC EIT-RM) are presented in detail. We focus on activities dedicated to educationEducation as well as validation and acceleration actions of the EIT-RMEIT RawMaterials, The. Regarding the former, activities tackling the awareness of citizens on the impact of RMs in our life, guiding pupils towards an informed engagement into RMs university carriers, and lifelong learningLifelong learning of professionals dedicated to methodologiesMethodology to access, organize, and share scientific literature and data are presented. Regarding the validation and acceleration actions, two main activities are discussed: (1) development of Platinum–Group Metals free catalysts and the corresponding know-how transfer initiative towards East and South East Europe (ESEE) countries; (2) development of novel analytical logging tools and portable devices for real-time compositional analyses based on laser technologies.

The recoveryRecovery of valuable and critical metals from electronic wastes (e-waste)E-waste via the pyrometallurgical route has some challenges including high processing temperatures. Designing appropriate slagSlag systems based on the major elemental components in e-wasteE-waste could bring operational advantages by lowering the liquidusLiquidus temperature. In this study, the quaternary slagSlag system CaO–Al2O3–SiO2–Na2O was investigated to determine the liquidusLiquidus temperature and phase equilibriaPhase equilibria of slagsSlag relevant to e-wasteE-waste smeltingSmelting. The slagsSlag were thermally equilibrated at different temperatures inside a vertical tube furnace followed by rapid quenching. The quenched slagsSlag were examined by SEM to observe the phase formed and the equilibrium compositions were determined using energy dispersive (ED) spectrometry. The liquidusLiquidus temperature of the slagsSlag in the anorthite (CaO·Al2O3·2SiO2) phase field was significantly decreased with increasing levels of Na2ONa2O. The slagSlag composition moved towards the pseudo wollastonite (CaO·SiO2) region upon the addition of Na2ONa2O.

Today some rawRaw materials materialsMaterials (RMs) have become essential in the manufacturing of common goods and technologies (i.e., mobile phones, computers, automobiles). Readily accessible rawRaw materials materialsMaterials, such as rare earthRare earths elementsRare earth elements (REEs), indiumIndium, neodymium, and others are important to industries and allow the transition towards a low-carbon economy. With the future global resource use projected to double by 2030, addressing rawRaw materials materialsMaterials through the entire value chain becomes a priority as well as transferring these ideas to youngsters. Some learning paths for pupils from 10 to 18 years old were developed in the framework of a European project, Raw Matters Ambassadors @SchoolsSchools (RM@SchoolsRM@Schools), funded by the Knowledge and Innovation Community “RawRaw materials MaterialsMaterials” of the European Institute of Innovation and Technology (KIC EIT-RM). It aims to increase among youngsters the understanding of how RMs are needed in modern society and to make careers in RM attractive. Thanks to a strategic European Partnership among the three sides of the knowledge triangle (research, educationEducation, and business), RM@SchoolsRM@Schools hasSchools developed learning pathways where different educational approaches are used to foster students’ interest in science and technology, in particular in circular economyCircular economy, and RM-related topics. The pathways are oriented toward a common goal: students are guided to become Young RM Ambassadors (science communicators) and create a “product” to be communicated outside of the class. By doing this, students develop twenty-first century learning skills such as creativity, critical thinking, awareness of responsibility, and teamwork.

Stone coalStone coal is a kind of carbonaceous shale that contains vanadium. The sequential chemical extractionsSequential chemical extraction were adopted to analyze the vanadium phasesVanadium phases of stone coalStone coal and its combustion fly ashCombustion fly ash. The results showed that the vanadium in stone coalStone coal mainly consisted in aluminosilicate. The vanadium in fly ash mainly existed in organic matter, aluminosilicate and Fe–Mn oxides, and the other vanadium existed in exchangeable fraction. Through the burning process, the vanadium was released and enriched in fly ash. Because of particular vanadium migration behaviors, the distribution of vanadium in phases became more scattered, and the leachingLeaching of vanadium in fly ash was easier than that in stone coalStone coal.

The solvo-chemical recoveryRecovery of Ce(IV) from sulfate leach liquorLeach liquor was investigated using Cyanex 923 in kerosene. The quantitative solvation of Ce(IV) could be achieved by performing three stages of counter-current extraction at an organic-to-aqueous phase ratio of 2:3, while using 0.15 mol/L Cyanex 923 into the organic phase. The spectroscopy analysisAnalysis of the organic phase revealed the formation of solvated species $$\overline{\left[{{\mathrm{Ce}(\mathrm{SO}}_{4})}_{2}\right].2\left[\mathrm{Cyanex }923\right].[{\mathrm{HSO}}_{4}^{-}]}$$ Ce ( SO 4 ) 2 . 2 Cyanex 923 . [ HSO 4 - ] ¯ into the organic phase. Stripping of Ce(IV) in its reduced form as Ce(III) was conducted in H2SO4 + H2O2 solution that yielding 1.3 g/L Ce(III) back into the aqueous phase. Finally, the recoveryRecovery of rare metalRare metals was conducted via Ce(III) precipitationPrecipitation with oxalic acid, which exhibited different characteristics with changing temperatures. PrecipitationPrecipitation kinetics showed good fits to the Avrami equation, while the determined activation energy (Ea, 8.6 kJ/mol) indicated to follow a diffusion-controlled mechanism.

Molybdenum (Mo)Molybdenum is a strategic metal element, and recoveryRecovery of Mo from low concentration Mo-containing solution is significant to alleviate the Mo resources shortage. In this study, the treatment of low-concentration Mo-containing solution by Fe3+ addition was investigated by batch experimentBatch experiment, and the effects of main parameters including molar ratio of n(Mo):n(Fe), pH value, initial concentrations, and reaction time on the recoveryRecovery of Mo were studied. The results showed that Mo is precipitated rapidly, with a Mo recoveryRecovery of 100% in 5 min when the pH range is 4–6 and molar ratio of n(Mo):n(Fe) is greater than 1:3, indicating the reaction between Mo and Fe readily approaches chemical equilibrium. Moreover, the initial concentration of Mo in the solution has little influence on the recoveryRecovery of molybdenumMolybdenum. This technology has potential to be applied for the enrichment and recyclingRecycling of molybdenumMolybdenum, while at the same time meeting the industrial discharge standard for the effluent.

The high-chromium vanadium slagSlag is treated by magnesium roasting-acid leachingLeaching to obtain Cr-containing tailings,Cr-containing tailings which are not the solid waste but important valuable resources for various fields. In order to extractExtract Cr from these tailings, sodium carbonate as annexing agent mixed tailings was roasted and then leached by water. There are several factors that were investigated including roasting temperature, roasting time, the molar ratio of Na/(V+Cr), leachingLeaching time, leachingLeaching temperature, and the ratio of L/S. The Cr-containing tailingsCr-containing tailings before and after roasting and the residue after leachingLeaching were characterized by XRD. It is indicated that Cr in tailings was all entered into leachingLeaching solution due to residue not found Cr-containing phase. Under the optimal conditions, the maximum leachingLeaching rate of Cr was 92.49%.

An aeration stepAeration step of the Becher processBecher process was carried out in a novel tubular reactorTubular reactor to study the effect of the tubular reactorTubular reactor on the removal of metallic ironMetallic iron. In the tubular reactorTubular reactor, the influence of oxygen flow rateInfluence of oxygen flow rate, The and stirring rate on the removal of metallic ironMetallic iron in reduced ilmenite (RI)Reduced ilmenite were studied and compared with the kettle reactor. The results show that when the reaction system is 2% (w/v) ammonium chloride solution, the optimal condition is that 97% of metallic ironMetallic iron (MFe) can be removed from RI in 3 h. At the same time, the synthetic rutile (SR) obtained in the tubular reactorTubular reactor has less iron oxide precipitated inside its particles. The grade of TiO2 can reach 87%.