Demand For Rare Earth Elements Research Articles

Strategic evaluations and mining process optimization towards a strong global REE supply chain

Abstract Rare earth elements (REE) have turned from an inconspicuous group of raw materials to critical commodities in the last decade. The insatiable and continuously growing demand for rare earths combined with their small and opaque market has resulted in a global exploration boom that has led to the delineation of extensive resources on every continent. Nevertheless, the special boundary conditions that govern the REE industry require second thoughts and careful evaluations when it comes to the potential exploitation of such resources. Past mistakes, with respect to environmental impacts and uncertain investments, have resulted in an overall uncertainty whether the mining and beneficiation of rare earth elements can be a viable industry in a free market context. This paper attempts to record the erroneous practices of the past and use them as guidelines to strengthen the global REE supply-chain. Moreover, the paper focuses on the assessments that need to be made in order to optimize the mining process and reinforce the growth prospects of the market. An overall assessment tool for the mineability of rare earth deposits is also used to consolidate these evaluations and answer the question, if REE mining can be sustainable.

An EDTA-β-cyclodextrin material for the adsorption of rare earth elements and its application in preconcentration of rare earth elements in seawater

The separation and recovery of Rare earth elements (REEs) from diluted aqueous streams has attracted great attention in recent years because of ever-increasing REEs demand. In this study, a green synthesized EDTA-cross-linked β-cyclodextrin (EDTA-β-CD) biopolymer was prepared and employed in adsorption of aqueous REEs, such as La(III), Ce(III), and Eu(III). EDTA acts not only as cross-linker but also as coordination site for binding of REEs. The adsorption properties for the adsorption of REEs by varying experimental conditions were carried out by batch tests. The kinetics results revealed that the surface chemical sorption and the external film diffusion were the rate-determining steps of the adsorption process. The obtained maximum adsorption capacities of EDTA-β-CD were 0.343, 0.353, and 0.365mmolg−1 for La(III), Ce(III) and Eu(III), respectively. Importantly, the isotherms fitted better to Langmuir than Freundlich and Sips models, suggesting a homogenous adsorption surface for REEs on the adsorbent. Moreover, the multi-component adsorption, which was modeled by extended Sips isotherms, revealed adsorbent’s selectivity to Eu(III). More significantly, the successful recoveries of the studied ions from tap water and seawater samples makes EDTA-β-CD a promising sorbent for the preconcentration of REEs from diluted aqueous streams.

A Detailed Assessment of Global Rare Earth Element Resources: Opportunities and Challenges

Rare earth elements (REE) are indispensable to infrastructure, technology, and modern lifestyles, which has led to an increasing demand for these elements. The current global rare earth oxides (REO) market is dominated by Chinese production, which peaked in 2006 at 133,000 tonnes REO per year, accounting for some 97.1% of global production, causing concern about the long-term supply of REE resources. Although the REE consist of 17 individual elements (15 lanthanides plus scandium and yttrium) that are hosted by numerous types of mineralization, the relatively modest scale of the global REE mining sector has limited our knowledge of REE mineral resources and mineralizing systems compared to metals such as copper and iron, which are produced in much larger quantities. In order to quantitatively analyze the mineralogy, concentrations, and geologic types of REE deposits, we compiled a global dataset of REE mineral resources based on the most recently available data (2013–2014). This compilation yields minimum global contained total rare earth oxides plus yttrium oxide (TREO + Y) resources of 619.5 Mt split between 267 deposits. Deposits with available grade and tonnage data (260 of the 267 deposits in our database) contain some 88,483 Mt of mineral resources at an average concentration of 0.63% TREO + Y, hosting 553.7 Mt TREO + Y. Of the 267 total deposits in our database, some 160 have mineral resources reported using statutory mining codes (e.g., JORC, NI43-101, SAMREC), with the remaining 107 projects having CRIRSCO-noncompliant mineral resources that are based on information available in the industry literature and peer-reviewed scientific articles. Approximately 51.4% of global REO resources are hosted by carbonatite deposits, and bastnasite, monazite, and xenotime are the three most significant REE minerals, accounting for >90% of the total resources within our database. In terms of REE resources by individual country, China dominates currently known TREO + Y resources (268.1 Mt), accounting for 43% of the global REO resources within our database, with Australia, Russia, Canada, and Brazil having 64.5, 62.3, 48.3, and 47.1 Mt of contained TREO + Y resources, respectively. Some 84.3 Mt TREO + Y is hosted within tailings (dominated by tailings from Bayan Obo but with smaller resources at Palabora, Steenkampskraal, and Mary Kathleen) and 12.4 Mt TREO + Y is hosted by monazite within heavy mineral sands projects, illustrating the potential for REO production from resources other than traditional hard-rock mining. Global REE resources are dominated by the light REE, having an average light REO (LREO; La-Gd) to heavy REO (Tb-Lu and Y) ratio of 13:1. These REE deposits contain an average of 81 ppm Th and 127 ppm U, indicating that radioactive waste associated with REE extraction and refining could be a concern. Modeling the 2012 global production figures of 110 kt TREO + Y combined with an assumed 5% annual growth in REE demand indicates that known REE resources could sustain production until 2100 and that geologic scarcity is not an immediate problem. This suggests that other issues such as environmental, economic, and social factors will strongly influence the development of REE resources.

World Crisis of Rare Earth – Inoculants Enhancer Solution for Ductile Iron Production

The unique properties of rare earth elements (REE) have resulted in their being crucial to a growing number of emerging technologies. As the demand for REE currently exceeds annual production, the present worldwide crisis for REE will probably continue for the foreseeable future. Hence, it is highly likely that the availability of REE used in the metallurgy of cast iron will be significantly reduced and alternatives to REE usage may have to be developed. Graphite nodules nucleate heterogeneously on particles formed in the melt, having a duplex structure (sulphide as a core and oxide/silicate as a shell). Mg, Ca and REE appear to act in the nucleation first stage, while Si, Al, Mg, REE, Ca, Sr and Ba act predominately in the second stage. Generally, REE are employed in ductile irons to accomplish the following tasks: (a) neutralize tramp elements such as Ti, Pb, Bi, As etc; (b) assist in nodulizing or provide a supplementary effect to Mg to promote spheroidal graphite shapes; (c) assist in nucleating graphite. When anti-nodularising Thielman control factors (K) are less than 0.8, REE are usually not required since there are no trace elements to neutralize. REE are useful for K factors between 0.80 to 1.20 and are mandatory for K factors greater than 1.20. Theilman factors greater than 2.0 will always require REE. When Theilman factors are less than 0.80, REEreslevels of 0.01% are usually more than sufficient for ductile iron production. Three ductile iron inoculation alloys were selected for this research: (a) a conventional Ca bearing 75% FeSi inoculant (Ca-FeSi), used at a high consumption level; (b) an improved conventional Ca-FeSi alloy that incorporated active inoculating elements, such as Ba or REE, used at a medium consumption level, and (c) a combination of a commercial inoculant, such as Ca-FeSi alloy, used with a separate oxy-sulphide inoculant enhancer alloy addition. The last inoculation variant provided the best structural parameters and the lowest consumption level.

Heavy rare earths, permanent magnets, and renewable energies: An imminent crisis

This article sounds the alarm that a significant build-out of efficient lighting and renewable energy technologies may be endangered by shortages of rare earths and rare earth permanent magnets. At the moment, China is the predominant supplier of both and its recent rare earth industrial policies combined with its own growing demand for rare earths have caused widespread concern. To diversify supplies, new mining—outside of China—is needed. But what many observers of the “rare earth problem” overlook is that China also dominates in (1) the processing of rare earths, particularly the less abundant heavy rare earths, and (2) the supply chains for permanent magnets. Heavy rare earths and permanent magnets are critical for many renewable energy technologies, and it will require decades to develop new non-Chinese deposits, processing capacity, and supply chains. This article clarifies several misconceptions, evaluates frequently proposed solutions, and urges policy makers outside of China to undertake measures to avert a crisis, such as greater support for research and development and for the cultivation of intellectual capital.

Environmental Life Cycle Perspective on Rare Earth Oxide Production

Rare earth elements (REEs) are a collection of 17 chemical elements that are critical to the functionality of a host of modern commercial industries including emerging clean energy technologies, electronics, medical devices, and national defense applications. Despite their key importance in multiple industries, to-date there has been little emphasis on environmental systems analysis of REE production. Rapid growth in these industrial sectors could result in heightened global demand for REE. As such, assessing the broader ramifications of REE production on human health and the environment is crucial for guiding the sustainable development of these industries. In this study, life cycle assessment (LCA) is performed to evaluate the environmental impacts and resource intensity of producing rare earth oxides (REO) from the Bayan Obo mine located in Inner Mongolia, China. Analysis indicates that the mining, as well as extraction and roasting phase(s), had the greatest contribution to overall life cycle environm...

Impact of Light Emitting Diode Adoption on Rare Earth Element Use in Lighting: Implications for Yttrium, Europium, and Terbium Demand

Light emitting diode (LED) lamps use significantly less rare earth elements per lumen of light generated than their fluorescent lamp counterparts. As a result, the global demand for rare earth oxides used in lighting will eventually peak and decline, as the market share of LED lighting increases. The exact timing of this inflection point is dependent on a number of factors, including market growth rates, regional LED adoption rates, and the relative costs of LED and fluorescent lighting technology. Lighting market forecasts from the U.S. Department of Energy were used to estimate the timing of the inflection point for the United States. Domestic rare earth demand can peak as early as 2019. A similar dynamic is expected globally, with timing sensitive to the local LED adoption rate. The analysis did not account for the potential effects of new technologies that use rare earth elements or possible variations in growth rates due to the economic cycle.

Model-Based Comparison of Batch and Continuous Preparative Chromatography in the Separation of Rare Earth Elements

The demand for rare earth elements (REEs) is growing, while the future supply is uncertain. Their unique electronic characteristics make them irreplaceable, and the commercial value of pure fractions is high. A model-based simulation study is presented that compares batch chromatography with the twin-column MCSGP (multicolumn countercurrent solvent gradient purification) process for ion-exchange chromatography of the four-component system neodymium, samarium, europium, and gadolinium. The last three components are considered products with individual purity requirements of 99%. The twin-column process has been shown to be a good alternative to the batch process regarding modifier consumption and productivity since it enables internal recycling to achieve high purities. A new cut strategy for MCSGP is applied where subfractions are taken from each outlet. Two multiobjective optimizations with yield, solvent productivity, and productivity objectives show that the MCSGP process is a better alternative than batch chromatography.

希土類資源開発と自然放射線源の放射線防護

There is growing demand for rare earth elements as raw materials for industrial goods such as high performance magnet. Thus, rare earth resources attract a lot of strategic attention internationally. The rare earth ore often contains uranium and thorium, that are Naturally Occurring Radioactive Material (NORM). Usually, such radioactive substances almost remain in the waste yielded in the extraction process for rare earth elements. Therefore, radiation protection is required in all of operation phases from mining and refining to waste disposal, and it is appropriate to the purpose to use the reference level of intervention in the ICRP recommendation. To ensure resource development, it is important that sites where wastes were disposed of are reused under monitored natural attenuation of the chemical conditions of the wastes after early physical stabilization of the land. This paper illustrates current status of rare earth development along with related radiation protection issue.

レアアースの中長期需要予測に関する動向

The medium – long time rare earth demand forecast is important issue in order to create the material security strategy for enhancement of the global economic growth and implementation of innovation. In recent studies, there are several researches of medium – long term rare earth demand forecast, such as DOE (U.S. Department of Energy), Roskill, NIMS (National Institute for Material Science), and other researches by Yale University, MIT, and Tokyo University. Therefore, this paper aims to evaluate and compare these forecasts, focusing on data, method, and the results to clarify the trends of rare earth forecast. Moreover, this paper aims to introduce the new methodology of medium – long time demand forecast of dysprosium (Dy), a rare earth element, which being broadly used in automobiles, home appliances, HDD, etc. This new methodology of AIST is using ratio of dysprosium-carrying end-use products, weight ratio of dysprosium in end-use products, production of end-use products, which able to estimate quantitatively the influence of the strategies (for example, changes in recycling ratio or Dy ratio in end-use application). From the result, 740 (t/y) of domestic Dy demand was forecasted to be reduced, by producing Dy less permanent magnet and recycle in 2030. This new methodology was validated by evaluating the relationship between the future scenario of the Dyless strategy, and domestic Dy demand forecast. The result of this paper evidently confirms that rare earth demand forecast for each end use products is useful for strategy making of critical material security.

Scarcity of Rare Earth Elements

Rare earth elements (REEs) are important for green and a large variety of high-tech technologies and are, therefore, in high demand. As a result, supply with REEs is likely to be disrupted (the degree of depends on the REE) in the near future. The 17 REEs are divided into heavy and light REEs. Other critical elements besides REEs, identified by the European Commission, are also becoming less easily available. Although there is no deficiency in the earth's crust of rare earth oxides, the economic accessibility is limited. The increased demand for REEs, the decreasing export from China, and geopolitical concerns on availability contributed to the (re)opening of mines in Australia and the USA and other mines are slow to follow. As a result, short supply of particularly terbium, dysprosium, praseodymium, and neodymium is expected to be problematic for at least the short term, also because they cannot be substituted. Recycling REEs from electronic waste would be a solution, but so far there are hardly any established REE recycling methods. Decreasing the dependency on REEs, for example, by identifying possible replacements or increasing their efficient use, represents another possibility.

Recycling as a Strategy against Rare Earth Element Criticality: A Systemic Evaluation of the Potential Yield of NdFeB Magnet Recycling

End-of-life recycling is promoted by OECD countries as a promising strategy in the current global supply crisis surrounding rare earth elements (REEs) so that dependence on China, the dominant supplier, can be decreased. So far the feasibility and potential yield of REE recycling has not been systematically evaluated. This paper estimates the annual waste flows of neodymium and dysprosium from permanent magnets, the main deployment of these critical REEs, during the 2011-2030 period. The estimates focus on three key permanent magnet waste flows: wind turbines, hybrid and electric vehicles, and hard disk drives (HDDs) in personal computers (PCs). This is a good indication of the end-of-life recycling of neodymium and dysprosium maximum potential yield. Results show that for some time to come, waste flows from permanent magnets will remain small relative to the rapidly growing global REE demand. Policymakers therefore need to be aware that during the next decade recycling is unlikely to substantially contribute to global REE supply security. In the long term, waste flows will increase sharply and will meet a substantial part of the total demand for these metals. Future REE recycling efforts should, therefore, focus on the development of recycling technology and infrastructure.

Addressing criticality for rare earth elements in petroleum refining: The key supply factors approach

The group of elements known as the rare earth elements (REEs) is comprised of the 15 lanthanides. REEs are used in a number of technologies including catalysts for automobiles and petroleum refining, magnets for wind turbines and defense technologies, and phosphors in lighting and computer and TV screens. REEs are actually quite abundant in the earth′s crust. The elements are deemed “rare” because they are found in low concentrations and are difficult to extract economically. China holds 48% of the global REE reserves, and until 2012, production of REEs was almost exclusive to China. Over the past decade, China has been steadily decreasing its REE export quotas, reducing the supply of REEs available to the rest of the world. REEs are considered critical materials according to the National Science and Technology Council, which defines critical elements as those serving an essential function in the manufacture of a product, the absence of which would cause significant social consequence. Thus, it is extremely important for consumers of REEs to be aware of and understand the risks facing the supply REEs, as awareness is the first and most important step in developing strategies to mitigate risk. This report presents a mechanism for identifying the risks present in a supply–demand scenario and determining the criticality of an individual rare earth element under specific circumstances.In “A brief examination of supply and demand in REEs” section we briefly discuss the supply and demand for REEs. “REEs in petroleum refining” section examines the importance of REEs in fluid catalytic Cracking, the largest domestic U.S. use of REEs. “Determining REE criticality: The key supply risk methodology” section presents our key supply factor methodology of addressing the criticality of REEs. In “Scenario analysis” section we apply our methodology to three different possible scenarios affecting U.S. REE markets. “Example of criticality index for cerium considering the increased domestic supply scenario” section contains the results we derive from our methodology. Our conclusions are in “Criticality indexes: Results” section.

Surface characterisation of fergusonite

There is currently very little information on the physico–chemical properties of rare earth element bearing minerals, or on their processing. With the increasing demand for rare earths, this is something that needs to be addressed. This paper introduces some surface chemistry analysis of fergusonite (YNbO4), and the bubble particle attachment. Zeta potential measurements indicate adsorption of sodium oleate and, to a lesser degree, potassium amyl xanthate onto the surface, and an increase in attachment to an air bubble is observed at pH 4·5 and 6·5. At a pH of 10·5, no attachment is observed, whether in the presence of the reagents or not. This analysis, although initial, will be used to initiate flotation tests, in order to facilitate the selective recovery of fergusonite. Two extensively characterised minerals, one hydrophilic (quartz) and one hydrophobic (galena) were also investigated as a comparison.Il y a présentement très peu d’information concernant les propriétés physico-chimiques des minéraux porteurs d’élément de terre rare, ou de leur traitement. Avec l’augmentation de la demande des terres rares, on a besoin d’examiner cette question. Cet article introduit une certaine analyse de la chimie de surface de la fergusonite (YNbO4) et de l’attachement de bulle-particule. Des mesures du potentiel zêta indiquent l’adsorption d’oléate de sodium et, à un degré moindre, du xanthate amyle de potassium à la surface. On observe également une augmentation de l’attachement à une bulle d’air à un pH de 4·5 et de 6·5. À un pH de 10·5, il n’y a pas d’attachement, que ce soit avec ou sans agents réactifs. Cette analyse, bien qu’initiale, sera utilisée pour initier des essais de flottation afin de faciliter la récupération sélective de la fergusonite. On a également examiné, à titre de comparaison, deux minéraux caractérisés considérablement, soit un hydrophile (quartz) et un hydrophobe (galène).

Rare Earths: Future Elements of Conflict in Asia?

China’s sudden suspension of rare earth exports to Japan in September 2010 represented the opening of a new front in the international competition for natural resources. As the demands of the global economy change, the international demand for rare earths, which are used in a diverse range of high-tech industries, has also increased. As China is currently the largest rare earths exporter, its actions in regulating rare earths exports will directly affect the interests of other states in the supply chain. This paper therefore examines how China assumed this dominant position in the supply chain. It also looks at how major rare earths consumers such as Japan and South Korea are reducing their reliance on and vulnerability to Chinese rare earths supplies through means such as seabed exploration in disputed territories, which might contribute to geopolitical tensions and instability in the East Asian region.

Mineral chemistry of Rare Earth Element (REE) mineralization, Browns Ranges, Western Australia

‘Green energy futures’ are driving unprecedented demand for Rare Earth Elements (REE), underpinning significant exploration activity worldwide. Understanding how economic REE concentrations form is critical for development of exploration models. REE mineralisation in the Browns Ranges, Gordon Downs Region, Western Australia, comprises xenotime-dominant mineralisation hosted within Archaean to Palaeoproterozoic metasedimentary units (Browns Range Metamorphics). Mineralogical, petrographic and mineral–chemical investigation, including trace element analysis by Laser-Ablation Inductively-Coupled Plasma Mass Spectroscopy, gives insights into the mineralogical distribution and partitioning of REE, and also provides evidence for the genetic evolution of the Browns Range REE mineralisation via a succession of hydrothermal processes.Two main REE-bearing minerals are identified: xenotime [(Y,REE)PO4], which is HREE selective; and subordinate florencite [(REEAl3(PO4)2(OH)6] which is LREE selective. Two morphological generations of xenotime are recognised; compositions are however consistent. Xenotime contains Dy (up to 6.5wt.%), Er (up to 4.35wt.%), Gd (up to 7.56wt.%), Yb (up to 4.65wt.%) and Y (up to 43.3wt.%). Laser Ablation ICP–MS element mapping revealed a subtle compositional zoning in some xenotime grains. LREE appear concentrated in the grain cores or closest to the initial point of growth whereas HREE, particularly Tm, Yb and Lu, are highest at the outer margins of the grains. The HREE enrichment at the outer margins is mimicked by As, Sc, V, Sr, U, Th and radiogenic Pb. Florencite is commonly zoned and contains Ce (up to 11.54wt.%), Nd (up to 10.05wt.%) and La (up to 5.40wt.%) and is also notably enriched in Sr (up to 11.63wt.%) and Ca. Zircon (which is not a significant contributor of REEs overall due to its low abundance in the rocks) is also enriched in REE (up to 13wt.% ΣREE) and is the principal host of Sc (up to 0.8wt.%).Early, coarse euhedral xenotime has undergone fracturing, partial breakdown and replacement by florencite. Second generation xenotime occurs as abundant small blades commonly associated with acicular hematite. Mineralization is attributed to percolation of a volatile-rich, acidic fluid, possibly granite-derived, through porous arkose units. Late hematite may suggest mixing with meteoric water and subsequent oxidation. Field observations suggest that faults acted as fluid conduits and that brecciation, possibly associated with release of volatiles from the fluid, occurred along these faults.The data provide valuable constraints on chemical compositional trends in xenotime and coexisting minerals. Given the current surge in exploration for REE, this information will assist in the development of exploration models for comparable terranes.

Separation of Lanthanides by Continuous Chromatography

Rare earth elements (REE) are widely used in industrial products, such as magnets, superconductors, and batteries. As the worldwide demand of REEs was increasing drastically during the past decade and the applications require very high purity materials, more efficient purification processes are required. Among the purification methods proposed for REE, chromatography has been considered initially, but was then replaced by extraction in the production scale because of its higher cost. In this work, we investigate the possibility of using continuous countercurrent chromatography to decrease the purification cost. In particular, a model mixture of three REE species (praseodymium, cerium, and lanthanum) has been considered with the aim of purifying all three components in a single step to >95% with high yield. It is found that this performance can be achieved with a yield of 75.4% and a productivity increase of 5 to 15-fold with respect to batch chromatography. However, the productivity value remains too low (approximately 1 g per liter stationary phase and day) for large scale applications. This is due to the low loading caused by the limited solubility of the REE in the adopted buffer used. Possibilities to overcome this limitation are discussed.

Critical materials in the 21 century

Critical materials represent mostly metals having a big importance for the future of the economy in the European countries. It is very difficult to replace these critical metals by other metals. Because of their wide application, the demand for these metals is increased, but the production cannot follow their growing consumption. Rare earth elements (REE) belong to critical materials. They include 17 elements, very similar in terms of their chemical and physical properties due to their mineralogical structure (the best-known are lanthanum and thorium, which is radioactive). REE are divided into elements with a lower atomic mass and elements with a higher atomic mass. Heavier metals show a significantly lower presence in the upper earth crust. In 2010, the share of the REE production in China in the global production amounted to 97 %, constituting a near-monopoly in the world market. In different studies, the term “Strategic” is often used instead “of “critical” materials. The materials for military application are called “Strategic” (nickel). In comparison to strategic metals, critical materials have a big importance for the national economies of European countries (platinum group of metals, rare earth elements, cobalt). The European Commission prepared a strategic development plan for critical materials in the next twenty years. The rare earth elements The rare earth elements include 15 elements (Z=57 through 71) and Yttrium (Z=39) and scandium. Because of their reactivity and similarity, the REEs were found to be difficult to obtain.. Lanthanide elements with a low atomic number are generally more abundant in the earth crust than those with high atomic numbers. World demand for rare earth elements is estimated by Humphries (CRS Report for Congress) at 134.000 tons per year, with the global production of around 114.000 tons annually. Humphries has reported in 2010 that there is no rare earth mine production in the United States. The major uses for rare earth elements include applications in auto catalysts, petroleum refining, metal alloys, cell phones, portable DVDs, etc. Permanent magnets containing neodymium, gadolinium and dysprosium are used in numerous electrical components and generators for wind turbines. The primary defense application (underwater mine detection, satellite power and communication systems, radar systems,etc.) use new materials: Neodymium Iron Boron, Samarium Cobalt. REEs extraction from monazite is performed by dissolution in a hot concentrated base or acid solutions. After cooling, the hydroxides of REEs and thorium are recovered by filtration, and thorium is separated by dissolution and selective precipitation. Metallurgy of indium Indium belongs to the group of rare earth elements with a low melting point. Some addition of indium increases the strength, hardness and corrosion resistance of alloys. The most known producers are situated in Belgium, Canada, Russia, France and Japan. Indium is used as coating on metals applied in difficult operation conditions, and in semiconductor techniques for the production of diodes. It is formed as a semi-product after pyrometallurgical and hydrometallurgical treatment of sulphidic raw materials. Indium can be used with other valuable metals such as vanadium, thallium, gallium, germanium, and cadmium. The coating process based on Indium is performed by an electrolytic treatment on the surface. Metallurgy of yttrium Yttrium compounds found interesting application in many fields. In particular, yttrium is used in the manufacture of superconductors, in super alloys of nickel and cobalt, and solid oxide fuel cells. Yttrium oxide has a high melting point and is used in ceramics. The compounds of yttrium are also used as catalysts. The growing industrial application of the rare earth elements led to a growing interest in finding new technologies for their recoveries. The selective dissolution of yttrium from lanthanum is performed by ammonium carbonate leaching. Conclusion The EU Raw materials Initiative was decided to identify a list of critical raw materials at the EU level. The EU-report describes a selection of 41 minerals and metals. Then, 14 elements were chosen as critical materials fort the economy of the European countries in the next twenty years. The future use of REEs is expected to be increased in the European countries. About 90 % of metal alloys are produced in China. The price of rare earth elements is reduced for the consumers in China in comparison to some companies in the USA and Europe. Therefore, the European countries and the USA have protested against this situation. The selective winning of rare earth elements is the most important aim in the processing of raw materials. The combination of pyrometallurgical and hydrometallurgical methods might be a new way of solving this problem in the European countries.

Separation of praseodymium(III) from aqueous solutions by nanofiltration

The increased demand for rare earth elements in commercial products is increasing their production, which in turn increases public exposure to rare earth elements. The objective of the present work is to study the separation of praseodymium from aqueous solutions by a commercial nanofiltration membrane (NF-300) at various operating conditions. The permeate and feed samples were analysed with inductively coupled plasma atomic emission spectrometry (ICPAES) to find praseodymium [Pr(III)] concentration. The results indicated that the separation of Pr(III) ions increased with increase in applied pressure (2–10 bar) and cross flowrate (4–16 L min−1); and decreased with increase in feed concentration (10 mg L−1 PrCl3 – 100 mg L−1 PrCl3). The highest observed separation of the Pr(III) was found to be 89·07 and 84·20% for an initial feed concentration of 10 and 100 mg L−1 PrCl3 respectively. It was also observed that separation of Pr(III) increases to 99·28 and 99·30% in complexation step by using ethylene diamine tetra aceticacid (EDTA) and diethylene triamine penta aceticacid (DTPA) respectively, as the chelating agent has generally influenced by pH (2 –10).La demande accrue d’éléments de terres rares dans les produits commerciaux augmente leur production, ce qui, à son tour, augmente l’exposition du public aux éléments de terres rares. Le but de ce travail est d’étudier la séparation du praséodyme à partir de solutions aqueuses au moyen d’une membrane commerciale de nanofiltration (NF-300) sous diverses conditions d’utilisation. On a analysé les échantillons de perméat et d’apport au moyen de la spectroscopie d’émission atomique avec plasma induit par haute fréquence (ICPAES) afin de déterminer la concentration du praséodyme [Pr(111)]. Les résultats indiquaient que la séparation d’ions de Pr(111) augmentait avec une augmentation de la pression appliquée (2–10 bar) et de la vitesse de l’écoulement transversal (4–16 L min−1) et diminuait avec une augmentation de la concentration de l’apport (10 mg L−1 PrCl3 – 100 mg L−1 PrCl3). On a trouvé que la valeur la plus élevée de séparation observée pour le Pr(111) était de 89·07 ou de 84·20% pour une concentration initiale de l’apport de 10 ou de 100 mg L−1 de PrCl3, respectivement. On a également observé que la séparation du Pr(111) augmentait jusqu’à 99·28 ou 99·30% dans une étape de complexation en utilisant de l’acide éthylènediaminetétracétique (EDTA) ou de l’acide diéthylènetriamino-pentaacétique (DTPA), respectivement, comme agent chélateur, influencé généralement par le pH (2–10).

Proposal of Method for Evaluating Measures to Reduce Domestic Rare Earth Demand

Proposal of Method for Evaluating Measures to Reduce Domestic Rare Earth Demand