METHOD OF EXTRACTING RARE EARTH METALS FROM WET-PROCESS PHOSPHORIC ACID WHEN PROCESSING APATITE CONC

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FIELD : chemistry. SUBSTANCE : rare earth metals are ejected by extraction using an extractant of di-2-ethylhexylphosphoric acid (D2EHPK) with a gradual separation of the REM into three lanthanide concentrates containing heavy, containing Yb, Er, Y, Dy, Ho, Tb, an average containing Gd, Eu, Sm, and light, containing Nd, Pr, Ce, La. D2EHPK is used with a concentration for the heavy group - 0.54M, for the medium - 1.35M and for the light group - 2.8M. The extraction process is carried out at a ratio of the aqueous and organic phases of 2-4, the contact time of the phases is not more than 2 minutes, with a constant stirring speed of 900 rpm and a temperature of 298 K. Obtained extracts are directed to the backwash for the impurity ions of Fe 3+ organic phase solutions of sulfuric acid concentration from 20 to 40% obtaining rare earth metals concentrates on three mentioned groups. The degree of extraction by Yb, Er, Y, Dy, But, Nd, Pr, Ce is not less than 99%, for Gd, La is not less than 90% and for Eu, Sm, Tb not less than 75%. EFFECT : increased degree of uranium extraction. 3 dwg, 3 tbl, 3 ex