Biosorption as green technology for the recovery and separation of rare earth elements

The use of rare earth elements (REEs) is increasing, mainly due to the growing demand for electric vehicles and new applications in green technology. This results in annual growth of the in-use REE stocks and the amount of End-of-Life (EoL) products containing REEs. REEs are considered critical elements by the EU, mainly because the rest of the world is dependent on China’s supply. Recycling of REEs can help alleviate the criticality of REEs, however, no REEs are currently functionally recycled. In this study, the time-dependent behavior of REEs in copper matte-slag system in primary copper smelting conditions was investigated experimentally at a laboratory scale. Lanthanum and neodymium were chosen to represent all REEs, as they are generally found in the highest concentrations in EoL products, and because REEs all have similar chemical behavior. The experiments were conducted as a function of time in air and argon atmospheres. SEM-EDS, EPMA and LA-ICP-MS methods were used for sample characterization. The results of this work indicate that the REEs strongly favor the slag and the deportment to the slag begins almost instantly when the system reaches high temperatures. With increasing contact times, the REEs distribute even more strongly into the slag phase, where they may be recovered and recycled, if their concentrations are sufficiently high and a suitable hydrometallurgical process can be found.

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A sustainable green technology for separation and simultaneous recovery of rare earth elements and fluorine in bastnaesite concentrates

Separation and Purification Technology ◽

10.1016/j.seppur.2021.118380 ◽

2021 ◽

pp. 118380

Author(s):

Peng Cen ◽

Xue Bian ◽

Wenyuan Wu ◽

Baokuan Li

Keyword(s):

Rare Earth ◽

Rare Earth Elements ◽

Green Technology

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Global Deposits of Rare Earth Elements and Prospects in the Democratic Republic of Congo

10.21203/rs.3.rs-391267/v1 ◽

2021 ◽

Author(s):

Georges M. Kasay ◽

Anthony Bolarinwa ◽

Olawale K. Aromolaran ◽

Charles Nzolang ◽

Alain S. Kivava

Keyword(s):

Rare Earth ◽

Rare Earth Elements ◽

Permanent Magnets ◽

Democratic Republic ◽

Democratic Republic Of Congo ◽

Developing Economies ◽

Green Technology ◽

High Tech ◽

Republic Of Congo ◽

Air Conditioners

Abstract Rare earth elements (REE) are not as rare as their name indicate, but the deposits in which they are found at an economic interest are not very common. They are enriched in carbonatites, pegmatites, alkaline and per-alkaline igneous rocks, placers, laterites, veins, bauxites and iron adsorption clays. Economic deposits of REE are mined from 3 main minerals, which are bastnaesite, monazite and xenotime. REE have been widely used in many high-tech and green technology gadgets, including batteries, computer memories, permanent magnets, smartphones, solar panels, wind turbines, speakers, air conditioners and many other applications. Due to these applications, REE are sought after by many developed and developing economies. The Democratic Republic of Congo (DRC) is endowed with mineral potentials. Studies have speculated REE concentration in areas with carbonatite complexes such as Lueshe, Bingo and Kirumba. Other regions with REE potentials include pegmatites. A high weathering rate contributes to metals and REE deposition in lateritic profiles of pegmatites and other alkaline rocks. Additionally, there are placers in many locations of riverbanks. For example, the alluvial placers of Kabengelwa, Mashabuto and Obaye are enriched in monazite and contain significant quantities of rare earth oxides. We believe that, with more research and explorations, the DRC could be a potential target for future REE projects.

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Voltammetric and Spectroscopic Determination of Rare Earth Elements in Fresh and Surface Water Samples

Environments ◽

10.3390/environments5100112 ◽

2018 ◽

Vol 5 (10) ◽

pp. 112 ◽

Cited By ~ 3

Author(s):

Martin Makombe ◽

Charlton van der Horst ◽

Bongiwe Silwana ◽

Emmanuel Iwuoha ◽

Vernon Somerset

Keyword(s):

Rare Earth ◽

Detection Limit ◽

Rare Earth Elements ◽

Water Samples ◽

Spectroscopic Method ◽

Environmental Water ◽

Green Technology ◽

Environmental Water Samples ◽

Icp Oes

The increasing demand for rare earth elements in green technology, electronic components, petroleum refining, and agricultural activities has resulted in their scattering and accumulation in the environment. This study determined cerium, lanthanum and praseodymium in environmental water samples with the help of adsorptive differential pulse stripping voltammetry (AdDPSV) and inductive coupled plasma-optical emission spectroscopy (ICP-OES). A comparison of the results of these two analytical techniques was also made. The accuracy and precision of the methods were evaluated by spiking water samples with a known amount of REEs. The detection limit obtained for the stripping analysis was 0.10 μg/L for Ce(III), and 2.10 μg/L for combined La(III) and Pr(III). The spectroscopic method of determination by ICP-OES was applied to the same samples to evaluate the effectiveness of the voltammetry procedure. The ICP-OES detection limit obtained was 2.45, 3.12 and 3.90 μg/L for Ce(III), La(III) and Pr(III), respectively. The results obtained from the two techniques showed low detection limits in voltammetry; the ICP-OES method achieved better simultaneous analysis. This sensor has been successfully applied for the determination of cerium, lanthanum, and praseodymium in environmental water samples, offering good results.

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