NUST MISIS (Moscow, Russia):
Yushina T. I., Head of Chair, Candidate of Engineering Sciences, Associate Professor, yuti62@mail.ru

INFOMINE Research Group (Moscow, Russia):
Petrov I. M., General Director, Doctor of Engineering Sciences

Berezniki Branch of PNRPU (Berezniki, Russia):
Cherny S. A., Head of Chair, Candidate of Economic Sciences, Associate Professor

Research Institute of Comprehensive Exploitation of Mineral Resources of RAS (IPKON) (Moscow, Russia):
Petrova A. I., Postgraduate

The article provides an overview of the processing of mineral raw materials for the production of rare-earth metals (REM), the demand for which has been growing steadily over the past decade by 5–7 % annually. The output of products manufactured using REM currently amounts to $ 5 trillion. The main industrial sources of REM are bastnaesite, monazite, loparite, and ion-absorption clays. The processing of bastnaesite ores is characterized by the use of gravity concentration, magnetic separation, and flotation. As a result, the recovery of rare-earth metals into respective concentrates reaches 70–75 %, and the mass fraction of rare-earth metal oxides in them is 30–60 %. For monazite-containing ores, the methods of gravity concentration, magnetic and electrical separation are traditionally used. This technology allows recovering up to 70 % of rare-earth metals from the ore and obtaining 40 % commercial concentrate. Hydrometallurgical methods are used to process ion-absorption clays. Clays contain 0.05 to 0.5 % rare-earth metals with a high proportion of the dense (yttrium) group. Of these, 10 to 20 thousand tons of concentrates are produced annually, containing over 60 % of REM oxides. Gravity concentration of loparite ores using magnetic separation in a strong field enables obtaining concentrates containing 30 % of rare-earth oxides with the recovery of loparite into the concentrate of 79–81 %. These technologies ensure that REM and their compounds are globally manufactured in the amount of about $20 billion per year.

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