METHOD OF EXTRACTING RARE-EARTH ELEMENTS FROM WET-PROCESS PHOSPHORIC ACID Russian patent published in 2014 - IPC C22B59/00 C22B3/20 C01F17/00 

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 treating an apatite concentrate, and can be used in industry. Wet-process phosphoric acid heated to 65-80°C, which contains rare-earth elements and fluorine, aluminium, titanium and iron impurities, is mixed with ammonia in an amount which ensures the molar ratio NH₃:P₂O₅=(0.2-1.0):1. Ammonium fluoride is then added to the acid in amount of 20-30 g/l to obtain a suspension and transfer the main part of rare-earth elements and part of the impurity components into the precipitate. The precipitate of the rare-earth element concentrate is separated from the phosphoric acid solution.

EFFECT: extracting rare-earth elements with low consumption of the fluorine-containing precipitation agent, which simplifies further processing of the phosphoric acid solution into mineral fertiliser.

3 cl, 9 tbl, 4 ex