Minor element content, including radioactive elements and rare-earth elements, in rocks from the syenite complex at Roy Creek, Mount Prindle area, Alaska

1989 ◽  
Author(s):  
Theodore J. Armbrustmacher
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Minor Element ◽  
Element Content ◽  
Radioactive Elements

scholarly journals Two-Step Solvent Extraction of Radioactive Elements and Rare Earths from Estonian Phosphorite Ore Using Nitrated Aliquat 336 and Bis(2-ethylhexyl) Phosphate

Minerals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 388
Author(s):  
Silvester Jürjo ◽  
Liis Siinor ◽  
Carolin Siimenson ◽  
Päärn Paiste ◽  
Enn Lust
Keyword(s):  
Rare Earth ◽  
Solvent Extraction ◽  
Rare Earth Elements ◽  
Toxic Elements ◽  
Downstream Processing ◽  
Liquid Extraction ◽  
Aliquat 336 ◽  
Radioactive Elements ◽  
Improved Method ◽  
Ph Values

Estonian phosphorite ore contains trace amounts of rare earth elements (REEs), many other d-metals, and some radioactive elements. Rare earth elements, Mo, V, etc. might be economically exploitable, while some radioactive and toxic elements should be removed before any other downstream processing for environmental and nutritional safety reasons. All untreated hazardous elements remain in landfilled waste in much higher concentration than they occur naturally. To resolve this problem U, Th, and Tl were removed from phosphorite ore at first using liquid extraction. In the next step, REE were isolated from raffinate. Nitrated Aliquat 336 (A336[NO3]) and Bis(2-ethylhexyl) Phosphate (D2EHPA) were used in liquid extraction for comparison. An improved method for exclusive separation of radioactive elements and REEs from phosphorite ore in 2-steps has been developed, exploiting liquid extraction at different pH values.

scholarly journals Peningkatan Perolehan Uranium, Torium, dan Logam Tanah Jarang dalam Residu Pelarutan Parsial pada Pengolahan Monasit

EKSPLORIUM ◽  
2021 ◽  
Vol 42 (2) ◽  
pp. 141
Author(s):  
Novita Sari Fatihah ◽  
Mutia Anggraini ◽  
Afiq Azfar Pratama ◽  
Kurnia Setiawan Widana
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Rare Earth Metals ◽  
Ammonium Hydroxide ◽  
Deposition Process ◽  
Optimum Process ◽  
Process Conditions ◽  
Radioactive Elements ◽  
Partial Dissolution ◽  
Total Dissolution

ABSTRAK. Monasit merupakan mineral hasil samping pengolahan timah yang mengandung fosfat, logam tanah jarang, dan unsur radioaktif berupa uranium dan torium. Unsur-unsur tersebut dapat dimanfaatkan secara optimal jika terpisah satu dengan yang lainnya melalui proses pengolahan. Pengolahan monasit meliputi proses dekomposisi, pelarutan parsial, dan pengendapan. Pemisahan unsur logam tanah jarang dari unsur radioaktif dalam monasit dilakukan melalui proses pelarutan parsial, akan tetapi pemisahan tersebut belum optimal sehingga diperlukan proses lebih lanjut untuk meningkatkan perolehan unsur-unsur tersebut. Pada penelitian ini, proses tersebut dilakukan melalui dua metode yaitu pelarutan total dengan asam klorida (HCl) yang bertujuan untuk melarutkan semua unsur dalam endapan dan pengendapan dengan ammonium hidroksida (NH4OH) yang bertujuan untuk memisahkan unsur radioaktif dan unsur logam tanah jarang. Kedua metode tersebut dilakukan pada kondisi optimum proses dengan berbagai variasi pH, suhu, dan waktu. Berdasarkan hasil pengamatan diperoleh bahwa kelarutan optimum masing-masing unsur sebesar 67,6% uranium, 15,3% torium, dan 50,8% LTJ pada kondisi proses pelarutan pH 1, pada suhu 80°C selama 2 jam. Sedangkan pada proses pengendapan diperoleh recovery pengendapan masing-masing unsur sebesar 57% uranium, 75,7% torium, 4,8% logam tanah jarang pada kondisi pH 6. Berdasarkan data tersebut disimpulkan bahwa uranium, torium, dan logam tanah jarang dapat larut pada kondisi proses pelarutan pH 1, suhu 80°C selama 2 jam, dan dapat dipisahkan pada kondisi pH pengendapan 6.ABSTRACT. Monazite is a by-product of tin processing containing phosphate, rare earth elements, and radioactive elements such as uranium and thorium. These elements can be utilized optimally if separated from one another through processing. Monazite processing includes decomposition, partial dissolution, and precipitation processes. The separation of rare earth elements from radioactive elements in monazite is carried out through a partial dissolution process, but the separation is not optimal so that further processes are needed to increase the recovery of these elements. In this study, the process was carried out using two methods, namely total dissolution with hydrochloric acid (HCl) which aims to dissolve all elements in the precipitate and precipitation with ammonium hydroxide (NH4OH) which aims to separate radioactive elements and rare earth elements. Both methods were carried out under optimum process conditions with various variations in pH, temperature, and time. Based on observations, it was found that the optimum solubility of each element was 67.6% uranium, 15.3% thorium and 50.8% LTJ under the dissolving process conditions of pH 1, at 80°C for 2 hours. While in the deposition process, the precipitation recovery of each element is 57% uranium, 75.7% thorium, 4.8% rare earth metals at pH 6 conditions. Based on these data, it can be concluded that uranium, thorium, and rare earth elements can be dissolved at pH 1, at 80°C for 2 hours, and can be separated at pH 6 precipitation conditions.

scholarly journals Assessment of Trace Elements in Soils and Sediments in the Abandoned Mercury Mine Site in Puerto Princesa City, Philippines

2021 ◽  
Vol 38 (2) ◽  
Author(s):  
Jessie Samaniego ◽  
Cris Reven Gibaga ◽  
Alexandria Tanciongco ◽  
Rasty Rastrullo
Keyword(s):  
Heavy Metals ◽  
Rare Earth ◽  
Rare Earth Elements ◽  
Contamination Factor ◽  
Area Measurement ◽  
Open Pit ◽  
Radioactive Elements ◽  
Mercury Mine ◽  
Naturally Occurring ◽  
Soil And Sediment

An abandoned mercury mine area in Puerto Princesa City, which was previously operated by Palawan Quicksilver Mines, Inc. (PQMI) from 1953 to 1976, is known for its unrehabilitated open-pit of mercury-rich rocks and exposed mine waste calcine stockpiles in the vicinity. In order to establish an understanding on the geology of the abandoned mercury mine deposit and to obtain clues in determining the possible metal pollutants in the area, measurement of trace element concentrations of soil and sediments collected from the PQMI vicinity were conducted. Soil and sediment samples were analyzed for heavy metals, rare-earth elements and naturally occurring radioactive elements and determined its contamination factor as part of risk assessment. Analytical results showed that aside from mercury, several heavy metals (nickel, chromium, manganese) were found to be anomalous due to the geology of the area. Statistical analyses show that chromium, nickel and antimony present the highest contamination factor among the sampling groups. Mercury is found to have negative bias with higher rare earth elements concentration but positively correlated with arsenic, antimony, and thallium. In general, there is low concentration of rare earth elements (except for scandium) in comparison with its respective average crustal concentration. Due to the nature of geology in the area, naturally occurring radioactive elements influence is also minimal. The results of this study, especially on the assessment of soil and sediment pollutants, are recommended as guidance to its mine rehabilitation.

ANALYSIS OF TRACE RARE EARTH ELEMENTS IN MISCH METAL BY MEANS OF ITP-PIXE METHOD

1993 ◽  
Vol 03 (01) ◽  
pp. 89-102 ◽  
Author(s):  
JIAN-YING HU ◽  
TAKESHI HIROKAWA ◽  
FUMITAKA NISHIYAMA ◽  
GOJI KIMURA ◽  
YOSHIYUKI KISO ◽  
...  
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Inductively Coupled Plasma ◽  
Minor Element ◽  
Emission Spectrometry ◽  
Plasma Atomic Emission Spectrometry ◽  
X Ray ◽  
Minor Elements ◽  
Misch Metal ◽  
Pixe Method

A misch metal, an alloy of light rare earth elements, was analyzed by a new coupled analytical method, ITP-PIXE(isotachophoresis—Particle Induced X-ray Emission) : The sample solution containing ca.1 mg misch metal was separated and fractionated by the use of a preparative isotacho-phoretic analyzer. The dropwise fractions containing nanomole rare earth elements were analyzed off-line by PIXE. The matrix effect in X-ray measurement was reduced by the isotachophoretic removing of the dominant lanthanoids and preconcentration of the trace elements of interest. Consequently the minor elements, Sm, Gd, Tb, Dy, Ho, Er, Yb and Y could be determined accurately. The most trace element found was Yb (4ppm, 4ng in 1mg sample). The good accuracy of ITP-PIXE method was also demonstrated for several model samples of lanthanoids, where La was the dominant element and the thirteen lanthanoids were the minor elements. The ratio was varied from 500:1 to 50000:1. Even in the case of 50000:1, ca. 10% accuracy was achieved for each minor element except for Sm(23%), Gd(17%) and Yb(18%). The analytical results by ITP-PIXE were compared with those by means of ICP-AES(Inductively Coupled Plasma—Atomic Emission Spectrometry).

scholarly journals Penentuan Kondisi Optimum Proses Ekstraksi Uranium dan Torium dari Terak II Timah dengan Metode Pelindian Asam Sulfat dan Solvent Extraction Trioctylamine (TOA)

EKSPLORIUM ◽  
2019 ◽  
Vol 40 (1) ◽  
pp. 11
Author(s):  
Mutia Anggraini ◽  
Fuad Wafa Nawawi ◽  
Kurnia Setiawan Widana
Keyword(s):  
Rare Earth ◽  
Solvent Extraction ◽  
Rare Earth Elements ◽  
Organic Phase ◽  
Mixing Time ◽  
Economic Value ◽  
Extraction Process ◽  
Radioactive Elements ◽  
Tin Slag ◽  
Slag Processing

ABSTRAKTerak II timah merupakan produk hasil samping dari peleburan timah tahap kedua. Terak II timah ini mengandung unsur bernilai ekonomi tinggi berupa unsur radioaktif (uranium dan torium) dan logam tanah jarang (rare earth element). Unsur-unsur tersebut dapat dimanfaatkan apabila telah terpisah satu dengan lainnya. Proses pemisahan unsur radioaktif dan unsur logam tanah jarang telah dilakukan dengan metode pelindian asam sulfat. Hasil proses ini adalah endapan yang mengandung logam tanah jarang dan filtrat yang mengandung unsur radioaktif berupa uranium dan torium sulfat. Penelitian terkait pemisahan uranium dan torium hasil pengolahan terak II timah hanya sedikit dipublikasikan. Paper ini bertujuan untuk mengetahui efektifitas proses pemisahan uranium dan torium dengan metode solvent extraction menggunakan trioctylamine (TOA). Proses solvent extraction dilakukan dengan memvariasikan konsentrasi TOA yang digunakan, perbandingan fase aqueous dan fase organik (A/O) dan variasi waktu ekstraksi. Pada penelitian ini diperoleh kondisi optimum proses yaitu konsentrasi TOA 4%, perbandingan A/O 1 : 1, dan waktu pencampuran aqueous dan organik selama 2 menit. Pada kondisi ini uranium dan torium yang terekstrak masing-masing sebanyak 67% dan 0,84%. ABSTRACTTin slag II is a by-product of the second stage of tin smelting. The tin slag II contains high economic value elements in the form of radioactive elements (uranium and thorium) and rare earth elements. These elements can be utilized if they are separated from each other. The process of separating radioactive elements and rare earth elements has been carried out by leaching sulfuric acid method. The results of this process are residue containing rare earth elements and filtrates containing radioactive elements in the form of uranium and thorium sulfate. Research related to the separation of uranium and thorium sulfate in tin slag processing is only slightly published. This paper aims to determine the effectiveness of the uranium and thorium separating process by the solvent extraction method using trioctylamine (TOA). The solvent extraction process is carried out by varying the concentration of TOA used, comparison of the aqueous and organic phase (A/O) and variations in extraction time. In this study, the optimum conditions for the process were obtained at 4% of TOA concentration, 1 : 1 of A/O ratio, and mixing time of aqueous and organic phase for 2 minutes. In this condition, uranium and thorium which extracted were 67% and 0.84% respectively.

scholarly journals Studi Pendahuluan Pengendapan Cerium, Lanthanum, dan Neodymium dari Larutan Klorida Menggunakan Sodium Karbonat pada Pengolahan Monasit Bangka

EKSPLORIUM ◽  
2020 ◽  
Vol 41 (1) ◽  
pp. 37
Author(s):  
Kurnia Trinopiawan ◽  
Venny Nur Avifa ◽  
Yarianto Sugeng Budi Susilo ◽  
Ersina Rakhma ◽  
Yayat Iman Supriyatna ◽  
...  
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Sodium Carbonate ◽  
Feed Solution ◽  
Processing Route ◽  
Precipitation Process ◽  
Light Rare Earth ◽  
Radioactive Elements ◽  
Light Rare Earth Elements ◽  
Dissolution And Precipitation

ABSTRAK Mineral monasit sebagai mineral ikutan penambangan timah di Kepulauan Bangka Belitung mengandung unsur tanah jarang ringan, diantaranya Cerium (Ce), Lanthanum (La), dan Neodymium (Nd). Tujuan penelitian ini adalah untuk memperoleh konsentrat unsur tanah jarang karbonat melalui proses pengendapan dengan sodium karbonat (Na2CO3), serta menentukan pengaruh konsentrasi dan volume Na2CO3 terhadap recovery pengendapan Ce, La, dan Nd. Persiapan umpan dilakukan dengan mengikuti rute proses pengolahan monasit menggunakan metode basa meliputi tahapan dekomposisi, pelarutan, dan pengendapan unsur radioaktif. Recovery pengendapan tertinggi untuk Ce, La, dan Nd yaitu sebesar 10,84%, 7,81%, dan 2,68% pada penggunaan Na2CO3 dengankonsentrasi 30% wt dan volume 55 mL.ABSTRACT Monazite mineral as associated mineral of tin mining in Bangka Belitung Islands contains light rare earth elements like Cerium (Ce), Lanthanum (La), and Neodymium (Nd). The objective of this study is to obtain the concentrates of rare earth carbonate through the precipitation process with sodium carbonate (Na2CO3) and determine the effect of concentration and volume of Na2CO3 on the precipitation recovery of Ce, La, and Nd. The preparation of the feed solution was carried out by following the monazite processing route using the alkali method includes the stages of decomposition, dissolution, and precipitation of radioactive elements. The highest precipitation recovery for Ce, La, and Nd are 10.84%, 7.81%, and 2.68% respectively in the use of Na2CO3 with a concentration of 30% wt and a volume of 55 mL. 

scholarly journals Morphological studies of Benzene derivatives.—III. Paradibromobenzenesulphonates (Isomorphous) of the “Rare Earth” elements—a means of determining the directions of valency in tervalent elements

1912 ◽  
Vol 87 (594) ◽  
pp. 204-217
Keyword(s):  
Organic Chemistry ◽  
Rare Earth ◽  
Rare Earth Elements ◽  
Benzene Derivatives ◽  
Radioactive Elements ◽  
Systematic Application ◽  
Morphological Studies ◽  
The Subject ◽  
The Rare Earth

In a communication on the “Classification of the Elements” brought under the notice of the Society by one of us in 1902, a method of ordering the elements was advocated which was different, in essential respects, from that we owe to Mendeléeff, more especially in that it involved the systematic application of a principle dominant in organic chemistry—the principle of homology—in a manner and to an extent not generally recognised as necessary at that time. The subject has been further discussed in a recent lecture to the Royal Philosophical Society of Glasgow, various issues being considered which have been brought into prominence in the meantime— e. g . the atomic weights of argon and the allied inert elements, the nature of the radioactive, elements and the position of tellurium in the scheme of elements. An amended table of the elements put forward in the lecture referred to is reproduced on p. 205.

Rare-earth elements, thermal history, and the colour of natural fluorites

1987 ◽  
Vol 24 (10) ◽  
pp. 2082-2088 ◽  
Author(s):  
D. L. Naldrett ◽  
Andre Lachaine ◽  
S. N. Naldrett
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Absorption Spectra ◽  
Thermal History ◽  
Colloidal Particles ◽  
Radioactive Elements ◽  
Purple Colour ◽  
Naturally Occurring ◽  
Ionizing Radiations ◽  
Photo Acoustic Spectroscopy

The contents of La and of all 13 naturally occurring rare-earth elements (REEs) in samples of natural fluorites were determined by neutron activation analysis. The samples were chosen to test the relation of REE content to colour. Total REE contents of the samples ranged from 3.46 to 97.2 ppm; the range of the least abundant REE, Lu, was 0.031–0.57 ppm and the range of the most abundant REE, Ce, was 0.94–33.3 ppm. No relation was found between the absolute amounts nor the enrichment or depletion of a particular REE and colour. The absorption spectra from 400 to 700 nm were determined by photo-acoustic spectroscopy using a few milligrams of powdered fluorite sample. Optical absorption spectra were obtained for all samples including those that were too small or too opaque for transmission or reflectance methods. The absorption maxima obtained are similar to those reported by others for samples of similar colours. It is concluded that ionizing radiations from incorporated radioactive elements produce the divalent REE ions that account initially for purple colour. From the description given in the literature on the thermoluminescence of fluorites it is then shown that the thermal history can account for the ultimate colour. However, other factors, such as the presence of water vapour, oxygen, or hydrogen; variation in the growth rate of crystals; colloidal particles; and exposure to light, can contribute to the colour.

scholarly journals Characteristic of rare-earth element distributions in mud volcanic waters

2019 ◽  
Vol 488 (1) ◽  
pp. 71-73 ◽  
Author(s):  
V. V. Ershov ◽  
E. V. Elovskiy ◽  
I. N. Puzich
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Rare Earth Element ◽  
Earth Element ◽  
Total Content ◽  
Element Content ◽  
Rare Earth Element Content ◽  
Mud Volcanoes ◽  
Taman Peninsula ◽  
Heavy Lanthanides

The original results on the distribution of rare-earth elements in the waters of mud volcanoes in Sakhalin Island, Taman Peninsula and Azerbaijan are presented. It has been shown that mud volcanic waters with total content of rare-earth elements less than 0.5 mcg/l are enriched with heavy lanthanides and characterized by a deficiency for Cerium. The Yuzhno-Sakhalinsk mud volcano demonstrates higher rare-earth element content in active griffons according to our study.

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