PROCEDURE FOR EXTRACTION OF RARE EARTH ELEMENTS FROM PHOSPHO-GYPSUM Russian patent published in 2011 - IPC C22B59/00 C22B3/06 C22B3/24 

FIELD: metallurgy.

SUBSTANCE: procedure consists in acid extraction of compounds of rare earth elements from phospho-gypsum by mixing extract suspension, in separation of insoluble sedimentation of crystal gypsum from extraction solution and in extracting compounds of rare earth elements from extraction solution. Also, acid extraction is performed with solution of mixture of sulphuric and nitric acids at ratio from 3.2 to 1.2 and concentration from 1 to 3 wt % at ratio L:S (liquid : solid) from 4 to 5 during 8-12 min with simultaneous hydro-acoustic effect onto mixed extraction suspension. Rare earth elements are extracted from extraction solution by means of cation-exchanging sorption with infiltration of extraction solution through cation-exchanging filter.

EFFECT: increased degree of extraction of rare earth elements and 2 times reduced time for process at lower concentrations and volumes of acid reagents.

3 cl, 2 tbl, 4 ex