METHOD FOR EXTRACTING La (III) FROM AN AQUEOUS SOLUTION OF LANTHANUM (III) NITRATE OBTAINED DURING MONAZITE PROCESSING Russian patent published in 2021 - IPC C22B59/00 C01F17/229 B03D1/12 B03D101/02 

FIELD: rare earth metals.

SUBSTANCE: invention relates to the technology of processing ores and concentrates containing rare earth elements (REE), and can be used to obtain REE from low-concentrated or secondary raw materials at the stage of separation of the sum of lanthanides using the ion flotation method. La (III) is extracted from an aqueous solution of lanthanum (III) nitrate obtained by processing monazite. Monazite is leached to form an aqueous solution of REE, which is sulfatized to obtain double sulfates and filtered to form a solid and aqueous phase. Alkali is added to the aqueous phase and hydroxides are precipitated. The aqueous and solid phases are obtained. The solid phase is dissolved in HNO₃ to obtain the aforementioned aqueous solution of lanthanum (III) nitrate, to which an anionic surfactant, sodium dodecyl sulfate, is added as a collector in the molar ratio La(NO₃)₃:C₁₂H₂₅OSO₃NA = 1:3 in a concentration corresponding to the stoichiometry of the reaction for ion flotation, and sodium chloride to a concentration of 0.01 mol/l chloride ions. The resulting mixture is stirred for at least 15 minutes and the pH of the solution is adjusted from 7.8 to 8.6, undergoes thermostatic control at a temperature of 20 to 25°C. The resulting foam is destroyed with 2N sulfuric acid to obtain a foam product. The foam and water phases are analyzed for the content of lanthanum (III) cations and the distribution coefficient of lanthanum (III) cations between the aqueous and foam phases is calculated. The foam product is sent to the drying cabinet for thermal decomposition to produce lanthanum oxide.

EFFECT: method contributes to an increase in the distribution coefficients of lanthanum cations between the foam and aqueous phases, and consequently, the efficiency of extraction of lanthanum cations from solutions of their salts.

1 cl, 2 dwg, 2 tbl