Uranium processing - Leaching | Britannica
Uranium processing - Uranium processing - Leaching: Roasted uranium ores are leached of their uranium values by both acidic and alkaline aqueous solutions. For the successful operation of all leaching systems, uranium must either be initially present in the more stable hexavalent state or be oxidized to that state in the leaching process. Acid leaching is commonly performed by agitating an …
Removal of thorium and uranium from leach …
01-06-2020 · The leaching rate of uranium and thorium is also much higher than that of other electrolyte systems. It is necessary to recover the associated uranium and thorium from the leach solution due to the potential radioactive pollution, especially for that obtained with aluminum sulfate as the leaching reagent.
Uranium mining - Wikipedia
Uranium mining is the process of extraction of uranium ore from the ground. The worldwide production of uranium in 2015 amounted to 60,496 tonnes. Kazakhstan, Canada, and Australia are the top three producers and together account for 70% of world uranium production. Other important uranium producing countries in excess of 1,000 tons per year are Niger, Russia, Namibia, Uzbekistan, China, …
(PDF) Leaching of uranium and thorium from red …
Leaching of uranium and thorium from red mud using sequential extraction methods Article (PDF Available) in Fresenius Environmental Bulletin 22(9a):2763-2769 · September 2013 with 781 Reads
(PDF) Leaching of uranium, radium and thorium …
Leaching of uranium, radium and thorium from vertisol soil by ground water Article (PDF Available) in Journal of Radioanalytical and Nuclear Chemistry 274(2):341-343 · November 2007 with 194 Reads
Uranium Ore - an overview | ScienceDirect Topics
When uranium is extracted by leaching with sulfuric acid, scandium is also dissolved into the leachate. Lash and Ross [172] reported that when the uranium ores were leached by sufuric acid, the leachate contained up to 1 mg/L of Sc 2 O 3. The uranium can be completely extracted with dodecyl phosphoric acid (0.1 M) from the leachate.
Preparation, sintering and leaching of optimized …
Preparation, sintering and leaching of optimized uranium thorium dioxides
RECENT DEVELOPMENT ON RECOVERY OF URANIUM, THORIUM …
Leaching of thorium cake in HNO 3 medium The thorium cake collected from IRE Ltd, was dissolved in HNO 3 medium in presence of trace amount of aqueous HF. The dissolution was carried out in Teflon beaker at boiling for a period of 8 hours. After dissolution of thorium cake, the un-dissolved solid was separated by filtration and it was observed that
Re-mobilization of uranium and thorium from sediments ...
for uranium and 1.24 ± 0.25 for thorium) for most samples except for one, which gives an indication that “hot” particles can lead to substantial discrepancies and that the samples are not entirely homogeneous at the mass of 300 mg as used for INAA. 4.2 Uranium and thorium leaching from the sediments
Options For Removing Uranium & Thorium From Zircon Mineral ...
Uranium & Thorium Radioactivity • Contains from 10 ppm up to 1% uranium & thorium. Very variable depending on source of zircon- cation substitution at the time of formation in original host rock • Market requirements of <500 ppm total uranium & thorium • There …
Uranium Bioleaching - MINTEK | MINTEK
In recent years, there has been an upsurge in uranium exploration across the globe, driven by a renewed interest in nuclear energy and higher uranium prices. In South Africa, uranium was produced as a by-product of gold production in the Witwatersrand Basin, but after the collapse of the uranium market in the 1980s, the uranium plants were mothballed and the uranium was retained in tailings ...
Acid Leaching of Uranium and Thorium Carbides | …
23-03-1963 · IN a recent communication by Sasaki et al.1 attention is directed to the use of the carbides of uranium, plutonium and thorium as nuclear fuels and to the problems associated with processing and ...
Uranium Acid Leaching - 911metallurgist.com
Table of ContentsMechanism of Thorium LeachingPrecipitate FormationBacterial ActivitySulphuric Acid Consumption Mechanism of Uranium Leaching: Uranium leaching with sulphuric acid is a complex process governed by stone dissolution, and the oxidation of uranium. It is controlled by surface etching, diffusion, and mass transfer within the ore. The physical parameters are in turn controlled by ...
Uranium and thorium leached from uranium mill …
The stone focused on the leaching behaviour of uranium (U) and thorium (Th) from uranium mill tailing collected from the Uranium Mill Plant in Northern Guangdong Province, China. Distilled water (pH 6) and sulphuric acid solution (pH 4 and 3) were used as solvent for the leaching over 22 weeks. It was found that the cumulative leach fraction from the mill tailing was 0.1, 0.1 and 0.7 % for U ...
Removing Uranium & Thorium From Zircon
Uranium & thorium Leaching of Malaysian Zircon at Various Heat Treatment Temperatures. • Eyal Y. and Olander d.R. 1990. Leaching of uranium & Thorium from Monazite: Initial leaching, Geomechanica Acta. 54: 1867-1877. • Ashraf M. Kinetics of Alkaline Pressure Leaching of Mechanically Modified zircon Concentrate. 2006.
Thorium Extraction Methods - UC Homepages
Uranium and thorium separation from rare earths by hydroxide precipitation. ... Electrochemical Leaching of Thorium Electrochemical leaching is an additional step that can be performed alongside bioleaching. Metal ions can be removed from liquid waste streams via electrodeposition.
Microbial Leaching of Uranium Ore - IntechOpen
Microbial Leaching of Uranium Ore Hadi Hamidian Islamic Azad University, Qaemshahr Branch Iran 1. Introduction This chapter is a review of the microbiological leaching of uranium ores. Microbiological leaching has been use as an alternative approach to conventional hydrometallurgical methods of uraniums extraction.
Leaching characteristics and kinetics of radioactive ...
09-01-2020 · The tantalum (Ta)/niobium (Nb) tailing is the tailing after smelting Ta/Nb ore. The tailing contains a certain amount of radioactive element uranium (U) and thorium (Th). U and Th from Ta/Nb tailing were leached by nitric acid and sulfuric acid. Leaching effect and kinetics were investigated under the conditions of different acid concentration, temperature, liquid–solid ratio and time.
Uranium Heap Leaching - nuclear-power.net
In-Situ-Leaching (ISL) Another method of uranium extraction is heap leaching. Heap leaching is an extraction process from ore which has been mined and placed in piles on the surface. Heap leaching is based on the use of a series of stone reactions that absorb specific minerals and re-separate them after their division from other earth materials.
Hydrometallurgical removal of uranium and thorium from ...
leaching behavior of uranium and thorium did not change significantly with varying sulphuric acid concentration from 70 to 90 wt%. Overall, the highest dissolution of uranium and thorium were achieved at 100°C, 70 wt% H 2 SO 4 concentration and 1 hr contact time. Keywords: leaching, tantalite, uranium, thorium 1. Introduction