METHOD OF EXTRACTING RARE-EARTH ELEMENTS FROM WET-PROCESS PHOSPHORIC ACID Russian patent published in 2012 - IPC C01F17/00 C22B59/00 

FIELD: chemistry.

SUBSTANCE: invention relates to methods of extracting a concentrate of rare-earth elements from wet-process phosphoric acid, which is obtained in a dihydrate process of processing an apatite concentrate, and can be used in chemical and related industries. The method involves sorption of rare-earth elements and thorium contained in wet-process phosphoric acid at temperature 20-85°C, wherein the sorbent used is a sulphoxide cationite, washing the saturated sorbent with water, desorption of rare-earth elements and thorium with concentrated ammonium sulphate solution to form a desorbate, and treating the desorbate with an ammonia-containing precipitant in form of ammonium carbonate or ammonia gas, which is fed in two steps, wherein at the first step the precipitant is fed until achieving pH 4.5-5.0 with precipitation and separation of a thorium-containing precipitate, and at the second step - until achieving pH of not less than 7 with precipitation and separation of a concentrate of rare-earth elements.

EFFECT: invention increases extraction of rare-earth elements while obtaining a non-radioactive concentrate of rare-earth elements.

4 cl, 4 ex