METHOD OF EXTRACTING RARE-EARTH METALS (REM) FROM PHOSPHOGYPSUM Russian patent published in 2014 - IPC C22B59/00 C22B3/08 C22B3/44 C01F17/00 

FIELD: metallurgy.

SUBSTANCE: proposed method comprises REM sulphuric acid leaching from gypsum pulp with application of ultrasound oscillations, separation of said pulp to REM productive solution and cake, precipitation of REM collective concentrate from productive solution with production of water phase. Pulp is prepared on the basis of sulphuric acid solutions processed by electrochemical activation. Note here REM leaching is conducted under conditions of pulp circulation at combined effects of ultrasound oscillations at cavitation and magnetisation. Leaching pulp is divided into REM productive solution and first cake. REM are precipitated from productive solution as REM oxalates with production of REM collective concentrate. Water phase after precipitation of oxalates is divided into to parts. One part is re-restored by sulphuric acid and subjected to electrochemical activation for use in circulation while another part is neutralised to get the second cake to be flushed combined with first cake and directed for gypsum production.

EFFECT: higher oxidative potential of leaching solution, lower consumption of reagents and their concentration.

9 cl, 3 dwg, 1 tbl, 1 ex