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Solubility of Eskisehir thorium/rare earth ores in sulphuric and nitric acids

Kursun I., Tombal T. D., Terzi M.

Physicochemical Problems of Mineral Processing

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2018

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Vol. 54, iss. 2

476--483

EN

Nuclear energy is considered as one of the most important energy resources in the world. Thorium (Th) has a significant potential to be used in electricity production by nuclear energy since its existence is not depended on the presence of another radioactive elements, and it has larger potential reserves than uranium. Bastnaesite ((Ce, La)CO3F) is one of the minerals from which Th can be economically extracted. In this study, solubility of bastnaesite containing ore obtained from Eskisehir, Turkey was investigated by leaching with H2SO4 and HNO3 in terms of leaching performance of thorium and some rare-earth elements (Ce, Nd, La). In this context, representative samples were taken from three different areas in Eskisehir-Kizilcaoren region, and a composite sample was prepared to be used for the leaching experiments. The effects of several parameters such as the solid ratio, leaching time, acid amount and pulp temperature, on dissolution efficiencies of Th, Nd, Ce and La was investigated. The best results were obtained using 3.42 mol/dm3 HNO3, solid–to–liquid ratio of 35%, 120 min leaching time and 60 oC temperature. Under these optimum conditions, the dissolution efficiencies of Th, Ce, Nd, and La were obtained as 94%, 82%, 77% and 70%, respectively.

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Recovery of trace elements with uranium and thorium from yatagan thermal power plant fly ashes by leaching

Kursun I., Ozkan S. G., Kilic A., Terzi M., Enkhtaivan N.

Physicochemical Problems of Mineral Processing

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2016

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Vol. 52, iss. 2

588--596

EN

In this paper, characterization of fly ashes obtained from the Yatagan Thermal Power plant, Mugla, Turkey was performed in order to determine their radioactive element contents, especially uranium and thorium. The representative fly ash samples were subjected to hydrochloric acid (HCl) leaching considering solid concentration, acid dosage, leaching time and temperature in order to reach certain uranium and thorium recoveries. The obtained results showed that the optimum conditions for leaching tests were: 30% solid concentration, 2.36 mmol/dm3 HCl addition, 240 min leaching time and 40 oC temperature. Dissolution efficiencies for uranium and thorium from the Yatagan Thermal Power Plant fly ashes were calculated as 90.12 and 81.18%, respectively.

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Beneficiation of low-grade feldspar ore using cyclojet flotation cell, conventional cell and magnetic separator

Hacifazlioglu H., Kursun I., Terzi M.

Physicochemical Problems of Mineral Processing

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2012

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Vol. 48, iss. 2

381-392

EN

In order to increase the quality of feldspar ore and to obtain sellable feldspar concentrate, it is necessary to remove coloring impurities such as iron and titanium contained in it. For the removal of coloring minerals from feldspar ore the most widely used method is reverse flotation method. Reverse flotation process is generally carried out in conventional mechanical cells. In this study, it was aimed to enrich low-grade feldspar by using cyclojet flotation cell which was developed as an alternative to conventional cell. Then, experiments were performed by using conventional cell and wet magnetic separator and the results were compared with the flotation results obtained by using cyclojet cell. In experimental studies, 200 micrometer grain sized feldspar (albite) ore obtained from Muđla province at the west side of Turkey was used. It was detected that the sample was containing 0.100% Fe2O3 and 0.360% TiO2 as coloring minerals. Cyclojet cell, conventional cell and magnetic separator reduced the Fe2O3 content down to 0.010%, but TiO2 content was different in the concentrates obtained by different devices. There was almost no reduction in TiO2 content by magnetic separation method. Cyclojet cell reduced TiO2 content down to 0.030% and mechanical cell reduced TiO2 content down to 0.020%. The weights of the concentrate were detected as the highest (92.70%) in magnetic separator and as the lowest (75.40%) in cyclojet cell. Therefore, it is possible to say that cyclojet cell can compete with mechanical cell and removal of TiO2 in cyclojet cell is much better than the removal of TiO2 in magnetic separator. Generally, in the flotation process performed by using a reagent of Aero801 and Aero825 mixture in natural pH medium, both Fe2O3 and TiO2 can be removed at a rate of up to 90%, but magnetic separator can only remove Fe2O3 mineral.