scholarly journals Nd(III) and Gd(III) Sorption on Mesoporous Amine-Functionalized Polymer/SiO2 Composite

Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 1049
Author(s):  
Khalid A. M. Salih ◽  
Mohammed F. Hamza ◽  
Hamed Mira ◽  
Yuezhou Wei ◽  
Feng Gao ◽  
...  
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
High Selectivity ◽  
Chemical Properties ◽  
Rare Earth Ions ◽  
High Tech ◽  
Low Grade ◽  
Selective Precipitation ◽  
Composite Support ◽  
Functionalized Mesoporous Silica

The strong demand for rare-earth elements (REEs) is driven by their wide use in high-tech devices. New processes have to be developed for valorizing low-grade ores or alternative metal sources (such as wastes and spent materials). The present work contributed to the development of new sorbents for the recovery of rare earth ions from aqueous solutions. Functionalized mesoporous silica composite was synthesized by grafting diethylenetriamine onto composite support. The physical and chemical properties of the new sorbent are characterized using BET, TGA, elemental analysis, titration, FTIR, and XPS spectroscopies to identify the reactive groups (amine groups: 3.25 mmol N g−1 and 3.41 by EA and titration, respectively) and their mode of interaction with Nd(III) and Gd(III). The sorption capacity at the optimum pH (i.e., 4) reaches 0.9 mmol Nd g−1 and 1 mmol Gd g−1. Uptake kinetics are modeled by the pseudo-first-order rate equation (equilibrium time: 30–40 min). At pH close to 4–5, the sorbent shows high selectivity for rare-earth elements against alkali-earth elements. This selectivity is confirmed by the efficient recovery of REEs from acidic leachates of gibbsite ore. After elution (using 0.5 M HCl solutions), selective precipitation (using oxalate solutions), and calcination, pure rare earth oxides were obtained. The sorbent shows promising perspective due to its high and fast sorption properties for REEs, good recycling, and high selectivity.

scholarly journals Editorial for Special Issue “Leaching of Rare Earth Elements from Various Sources”

Minerals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 164
Author(s):  
Kenneth N. Han
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
High Strength ◽  
Green Energy ◽  
High Tech ◽  
Special Issue ◽  
Important Group ◽  
Military Applications

Rare earth elements (REEs) have become an important group of metals used in many high-tech industries, including high-strength magnets, plasma TVs, various military applications, and clean and efficient green energy industries [...]

scholarly journals Pengaruh Berbagai Parameter Ekstraksi dalam Pemisahan Unsur Tanah Jarang dengan Metode Emulsion Liquid Membrane (ELM)

2021 ◽  
Vol 17 (1) ◽  
pp. 1
Author(s):  
Handias Meilinda ◽  
Novi Noviyanti ◽  
Anni Anggraeni ◽  
Diana Hendrati ◽  
Husein H Bahti
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Liquid Membrane ◽  
Chemical Properties ◽  
Membrane Phase ◽  
Emulsion Liquid Membrane ◽  
Phase Concentration ◽  
Stirring Time ◽  
Feed Phase ◽  
Physical And Chemical

<p>Unsur Tanah Jarang (UTJ) adalah 15 elemen kelompok lantanida, ditambah skandium dan itrium yang termasuk kelompok aktinida. UTJ memiliki banyak manfaat di berbagai bidang. Sifat fisik dan kimia yang mirip antar UTJ membuatnya sulit dipisahkan sehingga pemisahan UTJ menarik dipelajari dengan berbagai macam metode, salah satunya adalah dengan menggunakan <em>Emulsion Liquid Membrane </em>(ELM). ELM merupakan metode pemisahan yang dikembangkan dari ekstraksi pelarut terdiri dari tiga fase, yaitu fase eksternal (fase umpan) yang berisi UTJ yang akan dipisahkan, fase internal (fase pengupasan), dan fase membran. Fase membran berisi surfaktan sebagai penstabil dan ligan yang akan membentuk kompleks dengan UTJ pada antarmuka fase umpan dan membawanya berdifusi ke dalam fase pengupasan. ELM merupakan metode efektif untuk pemisahan karena tahap ekstraksi dan pengupasan (<em>stripping</em>) terjadi secara bersamaan dalam satu tahap dan fase membrannya dapat digunakan kembali. Pemisahan UTJ menggunakan metode ELM dengan berbagai ligan, seperti D2EHPA, Cyanex 572, P204, dan (RO)2P(O)OPh-COOH dipengaruhi oleh berbagai parameter, seperti konsentrasi ligan, pH fase umpan, waktu pengadukan ekstraksi, kecepatan pengadukan ekstraksi, rasio fase umpan, konsentrasi fase pengupasan, konsentrasi surfaktan, dan konsentrasi fase umpan. Parameter tersebut diseleksi untuk mendapatkan kondisi optimum sehingga meningkatkan efisiensi ekstraksi dan pengupasan yang berbeda.</p><p><strong>Effect of Various Parameters in Separation of Rare Earth Elements using the Emulsion Liquid Membrane (ELM) Method. </strong>Rare Earth Elements (REEs) are 15 elements of the lanthanide group, plus scandium and yttrium, which belong to the actinide group. REEs have many benefits in various fields. Similar physical and chemical properties between REEs make it difficult to separate, thus REEs separation is interesting to study by various methods, one of which is by using an emulsion liquid membrane (ELM). ELM is a method developed from solvent extraction consisting of three phases: the external phase (feed phase) which contains REEs to be collected, the internal phase (stripping phase), and the membrane phase. The membrane phase contains surfactants as stabilizers and ligands which will form complexes with REEs in the feed phase and are designed to diffuse into the stripping phase. ELM is an effective method to involve because extraction and stripping occur together in one glass and the membrane phase can be reused. Separation of REEs using the ELM method with various ligands, such as D2EHPA, Cyanex 572, P204, and (RO)2P(O)OPh-COOH influenced by various parameters, such as ligand concentration, feed phase pH, extraction stirring time, extraction stirring speed, feed phase ratio, stripping phase concentration, surfactant concentration, and feed phase concentration. These parameters are selected to obtain optimum conditions thereby increasing the efficiency of different extraction and stripping.</p><p> </p>

scholarly journals Study of the content of rare and rare earth elements in ash and slag waste of the Kemerovo state district power plant

2021 ◽  
Vol 315 ◽  
pp. 02004
Author(s):  
Tatiana Cherkasova ◽  
Anastasia Tikhomirova ◽  
Elizaveta Cherkasova ◽  
Andrey Golovachev
Keyword(s):  
Rare Earth ◽  
Power Plant ◽  
Rare Earth Elements ◽  
Inductively Coupled Plasma ◽  
Optical Emission ◽  
Emission Spectrometry ◽  
High Tech ◽  
Inductively Coupled ◽  
Ash And Slag Waste ◽  
Slag Waste

In the context of restrictions due to the sanctions imposed, a key factor in the country's development is the development of new Russian high-tech materials and their production technologies. The study of ash and slag waste from the Kemerovo State District Power Plant was carried out in this work using the methods of inductively coupled plasma optical emission spectrometry (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS). It has been established that matrix elements make up the predominant share of ash and slag waste. Rare and rare earth elements in terms of their content are classified as trace elements, however, some of them either have commercial values, or are close to it.

Using Electron Energy-Loss Spectroscopy (EELS) To Study Rare Earth Elements In Natural Crystals

2000 ◽  
Vol 6 (S2) ◽  
pp. 206-207
Author(s):  
Huifang Xu
Keyword(s):  
Rare Earth ◽  
Energy Loss ◽  
Rare Earth Elements ◽  
Electron Energy ◽  
Energy Resolution ◽  
Electron Energy Loss Spectroscopy ◽  
Relative Concentration ◽  
Chemical Properties ◽  
Similar Chemical ◽  
Electron Energy Loss

Because of similar chemical properties of the rare earth elements (Ree), whole series of the Ree may occur in natural Ree-bearing crystals. Relative concentration of the Ree may vary as the crystallization environments change. Electron energy-dispersive spectroscopy (EDS) associated with TEM is unable to resolve Ree and other coexistence elements, such as Ba nd Ti, because of peak overlap and energy resolution (∼ 150 eV) of EDS. Figure A indicate multiple peaks from Ce only. The Cu peaks are from Cu grid holding the specimen. Electron energy-loss spectroscopy (EELS) with energy resolution of < 1 eV is able to resolve all Ree in natural Ree-bearing crystals.Natural carbonate crystals from a Ree ore deposit were investigated by using EELS associated with field emission-gun (FEG) TEM. The crystals are in a chemical series of BaCO3 - Ree(CO3)F [1]. In Figure B, EEL spectra A and B are from Ce-rich and La-rich bastnaesite (Ree(CO3)F), respectively; spectrum D is from cordylite (BaCO3 (Ree(CO3)F); spectrum E is from huanghoite (BaCO3 Ree(CO3)F), spectrum F is from BaCO3; spectrum C is from an unknown Ree-rich phase.

Rare earth recovery from end-of-life motors employing green chemistry design principles

2016 ◽  
Vol 18 (3) ◽  
pp. 753-759 ◽  
Author(s):  
H. M. Dhammika Bandara ◽  
Kathleen D. Field ◽  
Marion H. Emmert
Keyword(s):  
Rare Earth ◽  
Green Chemistry ◽  
Rare Earth Elements ◽  
End Of Life ◽  
Recovery Rate ◽  
Design Principles ◽  
Selective Dissolution ◽  
Selective Precipitation ◽  
Efficient Process ◽  
Efficient Separation

This manuscript describes the development of an efficient process for the recovery of rare earth elements from materials mixtures such as in motors with a recovery rate of >80%. Selective dissolution enables efficient separation of steel and copper and selective precipitation of RE salts is the key for obtaining pure RE products.

scholarly journals Electrochemical behaviours of Eu(III)/E(II) and Ce(IV)/Ce(III) in H3PO4-H2O media : solvation and complexation reactions

2018 ◽  
Vol 149 ◽  
pp. 01092
Author(s):  
B. Belqat ◽  
S. Belcadi
Keyword(s):  
Rare Earth ◽  
Phosphoric Acid ◽  
Rare Earth Elements ◽  
Electrochemical Properties ◽  
Essential Elements ◽  
High Tech ◽  
Electrochemical Studies ◽  
Redox Potentials ◽  
Complexation Reactions ◽  
Phosphoric Acid Concentration

Many kinds of rare earth elements (REE) such as europium and cerium have been make them essential elements in many high-tech components. The electrochemical studies can be presented as an interesting indication for europium and cerium extraction from phosphoric solutions, including solvation and complexation reactions. The normal redox potentials of Eu3+/Eu2+ and Ce4+/Ce3+ systems have been determined in H3PO4-H2O media with various phosphoric acid concentration. The solvation of these elements in phosphoric media is characterized by their transfer activity coefficients "f" calculated from the corresponding normal redox potentials. The corresponding solvation increases with increasing the H3PO4 concentration. For each REE, the electrochemical properties depend on its number of charges and on its basic properties. Results suggest that solvation and complexation of REE phosphates are important in controlling REE concentration.

Preparation of Stabilized Zirconia Using A Mixture of Rare Earth Oxides as Dopant

1994 ◽  
Vol 346 ◽  
Author(s):  
Adelina P. Santos ◽  
Rosana Z. D. Fernandes
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Phase Diagrams ◽  
Chemical Properties ◽  
Dopant Distribution ◽  
Stabilized Zirconia ◽  
Stabilization Process ◽  
Physical Chemical ◽  
Natural Mixture ◽  
Cubic Structure

ABSTRACTThe present work deals with the effect of the rare earth nature and the content of the oxide dopants on the stabilization process of zirconia based ceramics. There are two main interests in our work. The first is to verify the possibility of stabilizing a cubic structure of zirconia using a natural mixture of rare earth elements as dopant, and second, to study and to characterize its basic physical-chemical properties such as phase diagrams, zirconia stabilization models and dopant distribution.

scholarly journals Metallurgical Evaluation of the Hoidas Lake Rare Earth Deposit

10.30544/507 ◽  
2020 ◽  
Vol 26 (2) ◽  
pp. 143-162
Author(s):  
Corby Gerard Anderson ◽  
Paul J Miranda
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Research Effort ◽  
High Tech ◽  
Heavy Rare Earth ◽  
Hybrid Car ◽  
Work Index ◽  
Bond Work Index ◽  
Heavy Rare Earth Elements ◽  
Metallurgical Evaluation

Hoidas Lake lies in the Northern Rae Geological Province, in the general vicinity of many of Saskatchewan's large uranium mines. The mineralogy of the Hoidas Lake rare-earth deposit differs from most other such deposits in that it is hosted in equal abundance in veins containing apatite and allanite mineral groups. Hoidas Lake also differs from other deposits in that it contains a significant amount of heavy rare-earth elements, such as dysprosium. This abundance of heavy Rare Earth Elements (REE’s) is significant, as there is a growing demand for the heavier rare earths in high-tech manufacturing (such as the use of dysprosium in the manufacturing of hybrid car components). Recently, metallurgical testing was performed on a Hoidas Lake REE deposit composite. These investigations included characterization, flotation testing, heavy media separation, magnetic separation testing, whole ore leaching studies, bond work index grindability testing, and relative abrasion index testing. This paper summarizes this research effort.

scholarly journals GEOLOGICAL INDUSTRIAL ASSESSMENT AND RANKING OF PROMISING OBJECTS OF THE DOMESTIC BASE OF RARE EARTH ELEMENTS

2021 ◽  
pp. 32-40
Author(s):  
V. Mykhailov ◽  
M. Kurilo ◽  
S. Kosharna
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Industrial Development ◽  
Raw Materials ◽  
Technological Development ◽  
Energy Transition ◽  
Green Energy ◽  
High Tech ◽  
Mining Operations ◽  
Field Development

Changes in the priority areas of financing in the field of subsurface use and their widespread reorientation to the search for alternative sources of raw materials which could ensure the development of modern high-tech industries are the promising direction for the country's growth in sustainable development conditions and Green Energy Transition. And at the moment the only resource that can ensure safe progress in the future and plays an important role in today's technological development is rare earth elements (REE). Within the framework of this study information on the current state of awareness about the REE mining prospects in Ukraine was analyzed and generalized; the systematization and updating of available data on quantitative and qualitative REE ore occurrences and deposits characteristics and their geological and industrial parameters was done; the main obstacles / barriers to the active mining development on these objects of potential extraction were identified. The obtained ranking results of domestic deposits and REE manifestations prove the expediency of investing in geological exploration and mining operations conducted in certain areas, which are identified as the most attractive for further industrial development and generally emphasize the prospects of the studied area and justify the need in intensification of selected rare earth objects field development.

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