scholarly journals Rare-earth metal ore processing technologies when developing new deposits

2020 ◽  
pp. 47-53
Author(s):  
T. I. Yushina ◽  
◽  
I. M. Petrov ◽  
S. A. Cherny ◽  
A. I. Petrova ◽  
...  
Keyword(s):  
Rare Earth ◽  
Raw Materials ◽  
Rare Earth Metals ◽  
Earth Metal ◽  
Dense Medium ◽  
Clear Trend ◽  
Processing Technologies ◽  
Hydrometallurgical Processing ◽  
Mass Fractions ◽  
Materials Used

The article provides a brief overview of processing technologies for rare-earth raw materials used under greenfield development projects in different countries of the world (Africa, Greenland, Australia, Canada). The projects feature deposits with different mineral compositions, mass fractions of rare-earth metals (REM) in ores of 0.2 to 15 %, and the presence of niobium, zirconium, tantalum, phosphorus, uranium, and thorium. The resulting production facilities will extract 180 kt to 7.2 Mt rare-earth ore annually to generate 1.5 to 20 kt oxides of heavy and light groups of rare-earth metals along with the rare metals. The analysis of technologies for the projects considered demonstrates that magnetic and radiometric separation, dense-medium concentration and flotation with hydrometallurgical processing in the form of leaching with sulfuric or hydrochloric acid, followed by extraction of the target products, will be used for the processing of rare-earth raw materials. A characteristic feature of a number of projects is, first of all, the direct hydrometallurgical processing of the feed. The concentration technologies for ores containing rare-earth metals also indicate a clear trend towards a more active use of high-intensity magnetic separation. The main products to be obtained with these technologies will include composite concentrates of oxides or carbonates of rare-earth metals. At the same time, the commissioning dates for the projects are being repeatedly postponed; the implementation of many projects remains uncertain, which is largely due to the stagnant dynamics of global prices for rare-earth metals.

scholarly journals BEHAVIOR OF RARE-EARTH METALS IN HYDROMETALLURGICAL PROCESSING OF PYROCHLOR-MONAZITE-GOETHITE ORES

2018 ◽  
Vol 13 (3) ◽  
pp. 64-71
Author(s):  
N. A. Permyakova ◽  
E. I. Lysakova ◽  
S. I. Anufrieva ◽  
E. G. Likhnikevich
Keyword(s):  
Rare Earth ◽  
Nitric Acid ◽  
Acid Solution ◽  
Nitric Acid Solution ◽  
Elevated Temperatures ◽  
Rare Earth Metals ◽  
Acid Leaching ◽  
Earth Metal ◽  
Hydrometallurgical Processing ◽  
Nitric Acid Leaching

The article is dedicated to finding out the specific features of the behavior of rare-earth metals in hydrometallurgical processing of pyrochlore-monazite-goetite ores of the Chuktukonsky ore field is shown in the work. Chuktukonsky ore field is a potential source of rare earth metals. The mentioned ores are practically unenforceable. Hydrometallurgical methods for their complex processing were suggested. Agitational and autoclave nitric acid leaching depending on such technological parameters as temperature, HNO3 concentration, process duration, S:L ratio and the use of H2O2 were studied. The possibility of transferring manganese (that is present in a significant amount in the ore) into a nitric acid solution by hydrogen peroxide was considered. Based on the results of the conducted studies, the distribution of REM in the products of the hydrometallurgical conversion of pyrochlore-monazitegoetite ore was estimated. It was found out that incomplete opening of the ore material was observed during agitational leaching: average REM recovery into the solution is 60%. The study made it possible to solve the problem of purifying nitric acid solutions from phosphorus that hinders the subsequent extraction and separation of rare earth metal ions forming strong complexes with rare earths. Removal of phosphorus from the solution was achieved by conducting the process under pressure at elevated temperatures (200-230 0C). It was found that the optimal decomposition conditions ensuring the transfer of almost 99% of the REM into the nitric acid solution are: 25% solution of HNO3, ore size - 0.071 mm; 5% by volume H2O2; t(160 0С) = 1 h; t(230 0С) = 1 h, gradual temperature increase from 160 to 230 0С; S:L = 1:8. Autoclave nitric-acid leaching allows selecting rare earth metals from the main part of iron, phosphorus and niobium.

Overview of processing technologies for the raw materials of rare-earth metals (REM) at existing enterprises

2020 ◽  
pp. 46-51
Author(s):  
T. I. Yushina ◽  
◽  
I. M. Petrov ◽  
S. A. Cherny ◽  
A. I. Petrova ◽  
...  
Keyword(s):  
Rare Earth ◽  
Raw Materials ◽  
Rare Earth Metals ◽  
Processing Technologies

FEATURES OF THE MAGNETIC STATE IN AMORPHOUS RE–TM AND RE–TM–B MAGNETS (review)

2021 ◽  
pp. 43-58
Author(s):  
R.B. Morgunov ◽  
◽  
D.V. Korolev ◽  
R.A. Valeev ◽  
V.P. Piskorskiy ◽  
...  
Keyword(s):  
Rare Earth ◽  
Amorphous Alloys ◽  
Magnetic State ◽  
Rare Earth Metals ◽  
Earth Metal ◽  
Spin Reorientation ◽  
Heavy Rare Earth ◽  
Temperature Dependences ◽  
Magnetic States ◽  
Amorphous Magnets

Provides an overview of the magnetism features of amorphous magnets of the RE–TM and RE–TM–B alloys (RE – rare earth metal, TM – transition metal, B – boron). Magnetic states in amorphous alloys, the effect of the single-ionic anisotropy of heavy rare-earth metals on local disorder and spin frustrations in an amorphous body, and some spin-reorientation transitions observed in such compounds are presented. It is shown that the identification of the spin-glass state can be achieved by detecting specific features on the field and temperature dependences of the magnetic moment and magnetic susceptibility of the sample.

Cathodes based on rare-earth metal nickelate ferrites prepared from industrial raw materials for solid oxide fuel cells

2014 ◽  
Vol 50 (6) ◽  
pp. 548-553 ◽  
Author(s):  
I. Yu. Yaroslavtsev ◽  
N. M. Bogdanovich ◽  
G. K. Vdovin ◽  
T. A. Dem’yanenko ◽  
D. I. Bronin ◽  
...  
Keyword(s):  
Rare Earth ◽  
Fuel Cells ◽  
Solid Oxide Fuel Cells ◽  
Rare Earth Metal ◽  
Raw Materials ◽  
Earth Metal ◽  
Solid Oxide ◽  
Oxide Fuel

International rare earth metals market and processing technologies: State-of-the-art and future prospects

2015 ◽  
pp. 76-82 ◽  
Author(s):  
T. I. Yushina ◽  
◽  
I. M. Petrov ◽  
S. I. Grishaev ◽  
S. A. Chernyi ◽  
...  
Keyword(s):  
Rare Earth ◽  
State Of The Art ◽  
Rare Earth Metals ◽  
Future Prospects ◽  
Processing Technologies

International rare earth metals market and processing technologies: State-of-the-art and future prospects

2015 ◽  
Author(s):  
T. I. Yushina ◽  
◽  
I. M. Petrov ◽  
S. I. Grishaev ◽  
S. A. Chernyi ◽  
...  
Keyword(s):  
Rare Earth ◽  
State Of The Art ◽  
Rare Earth Metals ◽  
Future Prospects ◽  
Processing Technologies

Secondary Resources of Rare Еarth Мetals

2020 ◽  
Vol 24 (9) ◽  
pp. 44-50
Author(s):  
S.A. Chernyi
Keyword(s):  
Rare Earth ◽  
Rare Earths ◽  
Industrial Waste ◽  
Rare Earth Metals ◽  
Nickel Metal ◽  
Nickel Metal Hydride ◽  
Processing Technologies ◽  
Apatite Concentrate ◽  
Fluorescent Lamps ◽  
High Processing

The article provides an overview of the main existing methods for recycling rare earth metals from various types of waste. It was noted that the demand for rare-earth metals is increasing annually due to the growth of advanced technologies, mainly in the sectors of electronics, power engineering and photonics. It has been established that in countries producing final products of high processing, the chemical-technological processes of processing goods that have worked out their life cycle, and, first of all, fluorescent lamps, NdFeB magnets from electronic devices, and nickel-metal hydride (NiMeH) batteries containing rare earths are most quickly created. The most profitable and recycling option is the reuse of products containing rare-earth metals, however, such technologies are applicable for a narrow range of waste. Another important area of REM recycling is the processing of industrial waste. For countries with developed mining and chemical industries, mining processing technologies are attractive. It is shown that for Russia, more appropriate are schemes for the disposal of industrial waste, primarily waste from the production of apatite concentrate. The main problems of the development of REM recycling are identified: low content and dispersion of rare earths in waste; the presence of impurities that impede the extraction of valuable components and the toxicity of the used recycling schemes.

scholarly journals Do rare-earth metals deter spiny dogfish? A feasibility study on the use of electropositive “mischmetal” to reduce the bycatch of Squalus acanthias by hook gear in the Gulf of Maine

2009 ◽  
Vol 66 (2) ◽  
pp. 315-322 ◽  
Author(s):  
Shelly M. L. Tallack ◽  
John W. Mandelman
Keyword(s):  
Rare Earth ◽  
Food Deprivation ◽  
Feasibility Study ◽  
Feeding Behaviour ◽  
Gulf Of Maine ◽  
Rare Earth Metals ◽  
Earth Metal ◽  
Field Studies ◽  
Squalus Acanthias ◽  
Spiny Dogfish

Abstract Tallack, S. M. L., and Mandelman, J. W. 2009. Do rare-earth metals deter spiny dogfish? A feasibility study on the use of electropositive “mischmetal” to reduce the bycatch of Squalus acanthias by hook gear in the Gulf of Maine. – ICES Journal of Marine Science, 66: 315–322. Catches of spiny dogfish (Squalus acanthias) are considered by commercial and recreational fishers to be unacceptably high during summer and autumn in the Gulf of Maine off the northeast coast of the USA. Consequently, there is interest in finding a dogfish deterrent for application in various fishing gears. Field studies tested triangular slices of the rare-earth metal cerium/lanthanide alloy (“mischmetal”) incorporated into longlines and rod-and-reel gear to assess its effectiveness in reducing dogfish catches. Treatment catches (mischmetal present) were compared with control (no mischmetal) catches. Laboratory studies provided video-taped, behavioural observations on the effects of alloys under variable levels of food deprivation and dogfish density. No significant reductions in dogfish catch were recorded for either rod and reel or longline, and in situ video footage verified persistent dogfish feeding behaviour, regardless of mischmetal presence. The laboratory trials found some evidence of avoidance behaviour in dogfish approaching treatment baits, but only with dogfish fed to satiation; no aversion to the material was observed after 2 and 4 d of food deprivation. Dogfish density had no effect on feeding behaviour in the laboratory. Overall, there is little evidence to suggest that mischmetal can significantly reduce catches of dogfish in hook gears in the Gulf of Maine.

scholarly journals Highly efficient stabilisation of meta-ethynylpyridine polymers with amide side chains in water by coordination of rare-earth metals

2015 ◽  
Vol 13 (6) ◽  
pp. 1700-1707 ◽  
Author(s):  
Hiroki Makida ◽  
Hajime Abe ◽  
Masahiko Inouye
Keyword(s):  
Rare Earth ◽  
Rare Earth Metal ◽  
Rare Earth Metals ◽  
Earth Metal ◽  
Helical Structure ◽  
Metal Salts ◽  
Side Chains ◽  
Highly Efficient

An amphiphilic meta-ethynylpyridine polymer with chiral amide side chains coordinated with rare-earth metal salts, especially strongly with Sc(iii), to stabilise its helical structure with CD enhancement.

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