I. V. Tananaev Institute of Chemistry and Technology of Rare Elements and Mineral Raw Materials of Kola Science Center of Russian Academy of Sciences, Apatity, Russia:

E. P. Lokshin, Chief Researcher, e-mail: lokshin@chemy.kolasc.net.ru
O. A. Tareeva, Researcher

This paper gives the results of investigations of rare-earth metal extraction from anthropogenic wastes and middlings of sulfuric acid processing of Khibiny apatite concentrate with mineral fertilizer obtaining (phosphogypsum and extraction phosphoric acid of dihydrate process: both productive and used for apatite concentrate decomposition). There was made the analysis of behavior of natural radionuclides (thorium and uranium), getting from apatite concentrate in phosphogypsums and extraction phosphoric acid in developed processes. There were found the technical solutions making possible the rare earths release from phosphogypsums without obtaining the middlings and dump waste products with increased radioactivity, which considerably simplifies their practical realization. There were compared the advantages and disadvantages of the developed methods of rare earth release from product and circulating extraction phosphorous acid, which part also allows the exclusion of the formation of middlings and dump waste products with increased radioactivity. There are shown the data about the correlation of individual elements in rare earths, released from various phosphogypsums and extraction phosphoric acid. There was made an assessment of the possible volumes of annual production of rare earths from Khibiny apatite concentrate with its sulfuric acid processing at Russian enterprises. Mastering the rare earth production during the sulfuric acid processing of apatite concentrates will completely meet the current and future requirements of Russia in rare earth products, create the potential for its export, and increase the complexity and economic efficiency of apatite concentrates processing.

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