METHOD OF EXTRACTING RARE-EARTH METALS FROM PHOSPHOGYPSUM Russian patent published in 2013 - IPC C22B59/00 C22B3/08 C22B3/24 

FIELD: chemistry.

SUBSTANCE: method includes leaching of rare-earth metals (REM) from phosphogypsum with 1-5% solution of sulphuric acid, REM sorption from leaching solution with cationite, REM desorption, precipitation of REM concentrate from desorbate, obtaining REM concentrate and mother liquor, which is used for REM desorption. Cationite after desorption is returned at sorption stage. Phosphor and fluorine are precipitated from mother liquor, phosphor -and fluorine-containing sediment are filtered and filtrate is used as return water in leaching. REM leaching and sorption are carried out simultaneously. Obtained pulp is filtered through mesh filter with separation of saturated REM cationite. After that, pulp is filtered with obtaining non-dissoluble residue and mother liquor of sorption. Before desorption cationite is treated with part of desorbate.

EFFECT: simplification of technology, reduction of duration of REM leaching and sorption, increased efficiency of sorption and desorption and concentrate quality.

12 cl, 1 dwg, 3 ex