Separation of Radioactive Elements from Ethiopian Kenticha Pegmatite Ore by Hydrometallurgical Methods
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The leaching and extraction behavior of uranium and thorium from a high-grade Ethiopian pegmatite ore in a mixture of hydrofluoric acid and sulfuric acid has been investigated. The effects of variables such as the temperature, particle size, acid concentration, and leaching time were studied. The leaching efficiency of uranium increased with increasing temperature to 150°C, at which 96% removal of uranium was achieved. Particles in the size range of − 100 + 75 μm resulted in the highest leaching of uranium, while formation of a colloidal suspension was observed when using a fine particle size fraction (− 75 μm). The dissolution of uranium increased with increasing leaching time. No significant systematic dependence of the leachability of thorium on the above variables was observed. Optimum extraction of uranium and thorium using D2EHPA was obtained when using aqueous/organic phase volume ratio of 1:1, solvent concentration of 0.3 M, and contact time of 20 min.
The authors would like to thank the Ethiopian Mineral Petroleum and Biofuel Corporation, Ethiopian Conformity Assessment Enterprise, Jimma University, Addis Ababa University, and Grace Trading for financial and in-kind assistance.
- 2.J.B. Lambert, Kirk-Othmer Encyclopedia of Chemical Technology, eds. D. Othmer and R.E. Kirk (Hoboken: Wiley, 2011).Google Scholar
- 4.G.J. Simandl, Tantalum market and resources: an overview. B. C. Geol. Surv. 1, 313 (2001).Google Scholar
- 5.O.M. EL-Husaini and M.N. EL-Hazek, Eur. J. Miner. Process. Environ. Protec. 5, 7 (2005).Google Scholar
- 7.V. Madakkaruppan, A. Pius, T. Sreenivas, and C. Sarbajna, J. Radioanal. Nucl. Chem. 309, 493 (2016).Google Scholar
- 10.G.G. Berhe, V.R. Alberto, B. Tadesse, A. Yimam, and G. Woldetinsae, Physicochem. Probl. Miner. Process. 54, 406 (2018).Google Scholar
- 11.C.K. Gupta and A.K. Suri, Extractive Metallurgy of Niobium (Boca Raton: CRC Press, 1994).Google Scholar
- 13.A.R. Adetunji, W.O. Siyanbola, I.I. Funtua, S.O. Olusunle, A.A. Afonja, and O.O. Adewoye, J. Miner. Mater. Charact. Eng. 4, 85 (2005).Google Scholar
- 15.A.H. Orabi, J. Rad. Res. Appl. Sci. 6, 1 (2013).Google Scholar
- 19.S.A. McMaster, R. Ram, J. Tardio, and S.K. Bhargava, International Symposium on Uranium Raw Material for the Nuclear Fuel Cycle, ed. J. Zellinger (Vienna: World Nuclear Association, 2014).Google Scholar
- 21.ASTM D6913/D6913 M-17, Standard Test Methods for Particle-Size Distribution (Gradation) of Soils Using Sieve Analysis (ASTM International, West Conshohocken, PA, 2017), https://compass.astm.org/EDIT/html_annot.cgi?D6913+17. Accessed 22 Mar 2018.
- 22.R.C. Merritt, The Extractive Metallurgy of Uranium (Golden: Colorado School of Mines Research Institute, 1971), pp. 59–61.Google Scholar
- 23.H.D. Mathur and O.P. Tandon, Chemistry of Rare Elements (New Delhi: S. Chand, 1986), p. 93.Google Scholar