EXTRACTION OF METALS FROM METAL COMPOUNDS Russian patent published in 2018 - IPC C22B59/00 C22B3/06 

FIELD: metallurgy.

SUBSTANCE: invention relates to recovery of rare earth metals from raw materials containing these elements. Selective extraction is carried out from saturated mother liquors in the form of oxalates of REE. Bittern is contacted with oxalic acid, followed by aging to precipitate the metal oxalates. Oxalates are separated from the depleted REE solution. Resulting solutions of rare-earth elements have extremely high purity and can be pretreated directly in the solvent extraction cycle for separation of rare-earth elements or can be post-processed for the direct production of 99.9 % of the bulk concentrate of hydroxides/oxides of rare-earth elements.

EFFECT: high purity of extracted rare-earth elements.

23 cl, 12 dwg, 5 tbl