Development of Technology for Production of Rhenium from Solutions Resulting from Uranium Ore Underground Leaching
Tech Area / Field
- CHE-IND/Industrial Chemistry and Chemical Process Engineering/Chemistry
3 Approved without Funding
The Republic State Enterprise “Center of the Sciences of the Earth, Metallurgy and Ores Benefication” Committee for Sciences, Ministry of Education and Science of the Republic of Kazakhstan, Kazakstan, Almaty
- “The Institute of High Technologies” LLP, the “Kazatomprom” National Nuclear Company, Kazakstan, Almaty
- G.M. Ritcey & Associates Inc., Canada, Ontario\nCenter for Advanced Mineral & Metallurgical Processing, USA, MT, Butte\nLaval University, Canada, QC, Quebec City\nUniversita degli Studi di L`Aquila / Dipartimento di Chimica, L`Aquila
Project summaryThe objective of the Project is the development of a combined sorption-extraction-electrodialysis process for recovering rhenium from solutions resulting from uranium ore leaching.
Rhenium is widely used in various industries, such as nuclear, aerospace, rocket production, petrochemical industries (heat-resistant and hard alloying compositions, oil reforming catalysts, exhaust gas neutralizes, and others) and demand for this rare element is constantly growing. To meet this demand, the development of new sources of raw materials is required. The price of rhenium in the world market is steadily increasing, and is currently at $2,100.00 USD per 1 kg.
Conventional sources of rhenium production are sulfide copper and molybdenum ores. In the Republic of Kazakhstan, the major source of rhenium production is cupriferous sandstone of Zhezkazgan deposit. Recently, uranium ores have considered as sources of raw materials for rhenium production. Kazakhstan takes one of the first positions in the world as concerns uranium reserves.
At present, a number of companies are operating in the territory of Kazakhstan using the underground leaching method for recovering uranium from ores. These uranium deposits are characterized by low content of rhenium: from 1 to 2 g/t, however, given the huge size of ore mass, each of these deposits contains quite considerable rhenium reserves exceeding, based on geological information, 100 tons. Sulfuric acid solutions, sodium and ammonium salts of carbonic acid are used as leaching reagents. Uranium is recovered from solutions by sorption on anionites followed by desorption of metal with inorganic reagents and precipitation of poorly dissoluble uranium compounds from eluates. Uranium-containing precipitates are processed using separate technology.
Rhenium content in solutions resulting from underground leaching is not higher than 0.2 – 0.4 mg/L. Though rhenium content in the solutions is low, a potential rhenium production by three mining pisions of “Kazatomprom” National Company could reach 6 tons per year.
A recently proposed method for biosorption recovery of rhenium tested based on rich and lean Zhezkazgan rhenium-containing solutions has proven to have no commercial prospects because of the following:
- high residual content of rhenium when it is recovered from rich solutions;
- low sorption ability of biomass when it is recovered from lean solutions;
- great consumption of biomass and single-time use of biomass;
- low efficiency of biosorption, inconsistent with solution amounts in uranium production;
- high cost of production of germs;
- lack of technological effectiveness of biomass processing for rhenium recovery.
Proponents of the Project have developed the process and undertaken the production of marketable ammonium perrhenate from by-products of copper, lead, and molybdenum industries in Kazakhstan. Current flowcharts for rhenium recovery imply waste solutions containing 1 to 5 mg/L rhenium. Therefore, a direct transference of the existing process is impossible.
The most acceptable methods for rhenium recovery from solutions with extremely low rhenium concentration can be a combination of such effective hydrometallurgical processes as sorption, extraction and electrodialysis.
To achieve this objective, the study will address the following issues:
- Adaptation of existence analytical methods of rhenium determination to various technological uranium-containing solutions containing extremely low concentrations of rhenium;
- Study of rhenium distribution in the processing of solutions resulting from underground leaching of uranium ore to produce “yellow cake”;
- Effect of major physical and chemical factors on primary rhenium concentrating from solutions resulting from underground leaching of uranium ore by sorption;
- Effect of major physical and chemical factors on desorption of rhenium;
- Effect of major physical and chemical factors on secondary rhenium concentrating by sorption and extraction;
- Purification of solutions from impurities by methods of recrystallization and electrodialysis and production of marketable rhenium compounds;
- Development of combined sorption-extraction-electrodialysis process for rhenium recovery from solutions resulting from underground leaching of uranium ore.
The following methods and approaches will be used:
- Adaptation of existence analytical methods for the identification of rhenium and impurities in solid and liquid products generated in the circuit of uranium ore underground leaching solutions.
- Optimization of rhenium recovery from solutions by identifying kinetic mechanisms and establishing a mechanism of sorption and extraction.
- Determination of optimal conditions of the crystallization for the production of high purity ammonium perrhenate.
- Based of the studies, the process will be developed for combined sorption-extraction-electrodialysis for rhenium recovery from solutions resulting from underground leaching of uranium ore.
- As a result of project implementation, minerals will be more comprehensively used in Kazakhstan, and new sources of raw materials will be involved in the production sector.
- Assortment of products in uranium industry will be enlarged together with a number of new work places;
- Additional production of critical metal will not result in pollution of the environment.
- Recommendations will be made for the commercial use of the developed process.
Role of Foreign Collaborators
Within the framework of the proposed Project, foreign collaborators’ contribution to the Project is envisaged in the form of the exchange of information, consultations on methods of final product testing, and the evaluation of processes developed in the course of the Project.
Meeting of ISTC objectives
The Project meets ISTC objections due to the following:
- More than 50% of personnel involved in the works under the Project are scientists and engineers who previously worked for military industries (weapon scientists and engineers);
- Project results will increase the comprehensive use of minerals in Kazakhstan, and new sources of raw materials will be engaged in rhenium production without pollution of the environment.
- Participation in ISTC Programme lets to increase the level of investigations due to integration in International scientific community;
- Production and commercial activity of enterprises that process uranium ore will be reoriented to civilian direction.