Extraction of Rare-Earth Metals During the Systematic Processing of Diaspore-Boehmite Bauxites
An integrated technology is proposed for processing diaspore-boehmite bauxites and extracting their useful components. It is established that sintering bauxite with a caustic alkali increases the quantities of rare-earth metals that are recovered. Experiments showed that the sintering of bauxite with a caustic alkali must be done with no more than 10–15% moisture in the charge at the optimum temperature of 200°C. Leaching of the sinter cake with water or a dilute aluminate solution forms high-iron red mud with low concentrations of alkali and alkaline-earth metals. Leaching the mud with a dilute inorganic acid makes it possible to extract up to 90% of the rare-earth metals, including scandium oxide.
Keywordsbauxite sintering caustic alkali red mud rare-earth metals scandium oxide
This research was performed with financial support provided in accordance with Resolution No. 211 of the Russian Federal Government (Contract No. 02.A03.21.0006).
- 1.Yu. G. Yaroshenko, “Modernizing technologies in nonferrous metallurgy – a high-priority plan for solving environmental problems,” Proc. 2nd Int. Interact. Sci.-Tech. Conf. Innovations in Materials Science and Metallurgy, Izd. Ural. Univ, Ekaterinburg (2012), pp. 137–143.Google Scholar
- 2.I. V. Loginova and A V. Kyrchikov, Alumina Production: Textbook, UGTU-UPI, Ekaterinburg (2010).Google Scholar
- 3.L. N. Komissarova, V. M. Shatskii, and V. A. Zhorov, “Behavior of scandium in solutions that contain carbonate-ions,” ZhNKh., No. 9, 2347–2351 (1971).Google Scholar
- 4.R. Den Hond, I. Hiralal, and Ab. Rijkeboer, “Alumina yield in the Bayer process: past, present, and prospects,” Light Metals, 37–42 (2007).Google Scholar
- 5.I. V. Loginova, V. A. Lebedev, S. F. Ordon, and A. V. Kyrchikov, “Improving the processing of Middle-Timan bauxites,” Tsvetn. Met., No. 7, 45–48 (2010).Google Scholar
- 7.I. V. Loginova, Yu. N. Loginov, S. F. Ordon, and V. A. Lebedev, Patent No. 2232716 RF, IPC C02F7/38, “Method of processing bauxites to obtain alumina,” subm. 05.05.2003, publ. 07.20.2004, Byull., No. 3.Google Scholar
- 8.L. P. Ni and O. B. Khalyapina, Physicochemical Properties of the Raw Materials and Products in the Alumina Industry, Nauka, Alma-Ata (1978).Google Scholar
- 9.A. I. Busev, V. G. Tiptsova, and V. M. Ivanov, Manual on the Analytical Chemistry of Rare Elements, Khimiya, Moscow (1978).Google Scholar
- 10.L. I. Vodolazov, V. A. Peganov, and D. N. Skorovarov, “Fundamental improvement of the technologies used to process uranium ores based on sorption and extraction,” in: VNIIKhT – 50 Years. Anniversary Collection of Articles, TsNIIAtominform, Moscow (2001), pp. 150–198.Google Scholar
- 11.V. M. Sizyakov and E. V. Tikhonova, “Physicochemical transformations of calcium in aluminate solutions used in alumina production,” Zh. Prikl. Khim., 85, No. 11, 1746–1750 (2012).Google Scholar