METHOD FOR EXTRACTION OF RARE EARTH METALS (REM) WHEN PROCESSING APATITE CONCENTRATE Russian patent published in 2021 - IPC C22B59/00 C01F17/00 C22B3/26 

FIELD: hydrometallurgy.

SUBSTANCE: invention relates to the hydrometallurgy of rare earth metals, in particular to the technology of isolation and separation of heavy rare earth metals (REM) from production solutions during the processing of apatite concentrate using an impregnated sorbent. Extraction isolation and separation of heavy REM are carried out from the technological solution with a solid extractant, di-2-ethylhexylphosphoric acid (D2EHPA), with a phase ratio T:L = 1:5-1:25, at a mixing speed of 60 to 90 sways/min, a phase contact time of 5 to 60 minutes and a temperature of 298 to 330 K. The resulting solution is filtered to obtain D2EHPA and a technological solution. Then D2EHPA is placed in a sorption column and an eluent is passed, as which oxalic acid, 1M is used, and a purified extract of D2EHPA and a solution of iron and titanium are obtained, which is sent for regeneration for reuse. Solutions of sulfuric acid of various concentrations are passed successively through the purified extract of D2EHPA, to obtain aqueous phases containing individual REM, and purified D2EHPA, which is returned for extraction, and first dysprosium is isolated with a solution of sulfuric acid concentration of 1 M, then yttrium and erbium 2 M and the last ytterbium, 4 M.

EFFECT: invention makes it possible to obtain solutions of individual REM compounds of the heavy group with a degree of extraction from technological solutions for processing apatite concentrate of at least 90%.

1 cl, 7 dwg, 3 tbl, 1 ex