(PDF) A uranium- and thorium-rich monazite from a south …
Electron microprobe analysis indicates a content of uranium (16% UO/sub 2/) which exceeds any previously-reported figure for members of the monazite group, and a moderately high content of thorium ...
Conceptual Process to Produce ThO2 from Monazite
Rare-earth (RE) extraction activities in Malaysia produce an average of 75000 tonnes of Water Leach Purification (WLP) residue containing an estimated 106 tonnes of thorium that leads to negative ...
A PROCESS FOR SEPARATING THORIUM COMPOUNDS FROM MONAZITE …
The process for production of pure Th and U compounds bas been improved and developed to the pilot-plant stage. This process consists of digestion of the monazite in H/sub 2/SO/sub 4/ dilution of the digested mass with H/sub 2/O, fractional neutralization with NH/sub 3/ in three stages, and producing Th-rich, rare-earth-rich, and U-rich fractions.
Geosciences | Free Full-Text | Assessment of Five Monazite …
Monazite is a common accessory phosphate mineral that occurs under a wide range of pressure and temperature conditions in sedimentary, metamorphic and igneous rocks. Monazite contains high amounts of Th and U, rendering single monazite grains suitable for in-situ U-Th/Pb dating using laser ablation inductively-coupled mass …
Economic analysis of thorium extraction from monazite
The aim of this study is to investigate the production cost of thorium oxide (ThO 2) resulted from the thorium extraction process. Four main parameters were …
Commercial approach for highly pure thorium from …
Thorium. Article PDF Available. Commercial approach for highly pure thorium from Egyptian monazite mineral acid process. January 2021. IOP Conference Series Materials Science and Engineering...
Production of rare earth and thorium compounds from monazite. Part I
Abstract. A process is described for the separation of rare earth elements in monazite into the following products : (a) cerium group hydroxides containing thorium hydroxide, (b) crude thorium ...
(PDF) Optimal Monazite Concentration Processes for the
The present work deals with a study of an innovative method for Egyptian monazite mineral digestion by 98%sulfuric acidin hydrothermal autoclaves, where the digtion of monazite take place.The aim ...
Economic evaluation of thorium oxide production …
open access. Abstract. Monazite is a phosphate mineral that contains thorium (Th) and rare earth elements. The Th concentration in monazite can be as high as 500 …
Separation, purification and recovery of thorium from monazite …
In this study, monazite thorium concentrates produced from Malaysian monazite were used. Thorium was extracted from an aqueous nitric acid medium with TBP (30%) in kerosene and Aliquat-336 (10% ...
(PDF) Thorium: Issues and prospects in Malaysia …
The average range of thorium content in Malaysian monazite and xenotime minerals was found about 70,000 and 15,000 ppm respectively. About 2,636 tonnes of Malaysian monazite was produced …
Recovery of rare earth elements, uranium, and thorium from monazite …
Quantitative recovery of rare earth elements (REEs), Th, and U by supercritical fluid extraction (SCFE) with carbon dioxide containing adducts of TBP and HDEHP with HNO3 directly from monazite concentrate (MC) powder is impossible and requires the conversion of the constituent elements into more soluble compounds. …
Thorium zoning in monazite: A case study from the …
Thorium concentrations obtained from in-field GRS data are denoted Th_GRS and are cast as ppm. FIGURE 3. Open in figure viewer ... Z1–Z9 refer to monazite zones described in text. Bright green areas in IV16-16 represent intergrowths of allanite and Th-orthosilicate [Color figure can be viewed at wileyonlinelibrary] In granulite facies ...
Thorium | SpringerLink
3.1 Separation of Thorium Compound from Monazite 3.1.1 Sulphuric Acid Method. Separation of thorium compound from monazite by sulphuric acid method has been in commercial use for many decades. The monazite sands are decomposed chemically in an excess of concentrated (93%) H 2 SO 4 at a temperature of 210 °C for a …
Monazite
Monazite occurs as accessory minerals in igneous, metamorphic, and sedimentary rocks. In addition, monazite is found throughout the world in placer deposits, beach sands, and is also a component of the ores of the Bayan Obo deposit (Table 6 and Fig. 20 ). Monazite is a phosphate mineral containing approximately 70% REE oxides.
Development of selective separation method for thorium …
The present work succeeded to develop new optional procedures to enhance the separation process of thorium and REEs. Selective precipitation of thorium with pyrophosphate was successfully attained for the upscale level in which, complete and efficient thorium separation (99%) was achieved with relatively low co-precipitation of …
Preparation of Optimized Uranium and Thorium Bearing
To read the full-text of this research, you can request a copy directly from the authors. ... Bregiroux et al. and Terra et al. developed uranium, cerium, plutonium and thorium containing monazite ...
(PDF) Thorium zoning in monazite: a case study from the
Z1 – Z9 refer to monazite zones described in text. Bright green areas in IV16-16 represent intergrowths of allanite and Th-orthosilicate Bright green areas in IV16-16 represent intergrowths of ...
Thorium zoning in monazite: A case study from the …
In the deep crust, volumetrically subordinate metasedimentary layers, which are source to crustal granites (sensu lato), host the majority of Th ± U, primarily within the REE + Th + U + Y phosphate mineral monazite. We examine the spatial and temporal distribution of Th within monazite grains in metasedimentary rocks from the lower crustal ...
Uranium- and thorium-rich monazite from a south-alpine …
@article{osti_6571402, title = {Uranium- and thorium-rich monazite from a south-alpine pegmatite at Piona, Italy}, author = {Gramaccioli, C M and Segalstad, T V}, abstractNote = {A green pegmatite mineral from Piona, northern Italy, originally described as a phosphate of lanthanum and cerium, has unit-cell parameters a = 6.78, b = 6.96, c = 6 ...
Production of high-purity ThO2 from monazite ores for thorium fuel
The present study aims to investigate the optimum parameter in producing high-purity thorium dioxide (ThO 2) using Di-2-ethylhexyl phosphoric acid (D 2 EHPA) and Aliquat-336 as solvent materials. The extraction and purification process was performed using [Th-RE](OH) 4 compound which was selectively precipitated from the monazite …
Malaysian monazite and its processing residue: chemical
The radium equivalent value of monazite ore and thorium hydroxide were measured as 333 Bq/g and 515 Bq/g, respectively, which were notably higher from the reference value 370 Bq/kg . The obtained results indicating that monazite ore and thorium hydroxide would bring radiological hazard to the environment and inhabitant.
(PDF) Thorium zoning in monazite: a case study from …
We examine the spatial and temporal distribution of Th within monazite grains in metasedimentary rocks from the lower crustal section of the Ivrea–Verbano …
Extraction of Thorium Oxide from Monazite Ore
The main goal of this study is to analyze the economic viability of thorium oxide recovery. from monazite ore. Considerations that went into the economic viability of the process …
Thermodynamic investigation of thorium and strontium …
In this paper, we report synthesis and characterization of thorium and strontium substituted synthetic monazite solid-solutions of general formula La 1-x Sr x/2 Th x/2 PO 4 (0≤x≤1) using solid ...
Monazite: A rare-earth phosphate mineral.
Monazite is a rare phosphate mineral mined from placer deposits for its rare earth and thorium content. ... The generic chemical formula for monazite, (Ce,La,Nd,Th)(PO 4,SiO 4), reveals that cerium, lanthanum, neodymium, and thorium can substitute for one another in the mineral's structure; and, substitution of silica for phosphate also occurs ...
Thorium zoning in monazite: A case study from the …
Open Access. Thorium zoning in monazite: A case study from the Ivrea–Verbano zone, NW Italy. Megan A. Williams, David E. Kelsey, Daniela Rubatto. First published: 11 …
Determination of Rare Earth Elements, Yttrium, Thorium
Analysis of monazite, an important mineral of rare earth elements (REEs), and thorium constitutes one of the toughest tasks in analytical chemistry as it is a highly resistant mineral and ...
Sulfuric Acid Baking and Leaching of Rare Earth Elements, Thorium …
Sulfuric acid based treatment of monazite for recovery of rare earths and/or thorium has a long history, going back to the early-mid 1900s, and typically involves treatment with concentrated sulfuric acid at elevated temperature followed by leaching in water or dilute acid [5,6,7].
Thorium: Issues and prospects in Malaysia
In Malaysia, thorium exists in minerals and rare earth elements production residue. The average range of thorium content in Malaysian monazite and xenotime minerals was found about 70,000 and 15,000 ppm respectively. About 2,636 tonnes of Malaysian monazite was produced for a period of 5 years (2006-2010) and based on the …
