METHOD OF EXTRACTING SCANDIUM AND RARE-EARTH ELEMENTS FROM RED MUD Russian patent published in 2016 - IPC C22B59/00 C22B3/24 

FIELD: chemistry.

SUBSTANCE: invention relates to extraction of scandium and rare-earth elements from red mud. Repulping of red mud is carried out at pH = 0.5-1. Pulp is subjected to mechanical activation, sorption leaching of scandium is carried out with an organic sorbent, whose pores are impregnated with a phosphoric ester. Sorbent before desorption is treated with a mixture of solutions of hydrofluoric acid and sulphuric acid. Scandium is desorbed with a suspension of calcium fluoride and hydrofluoric acid to produce scandium concentrate and a mother solution, which is post-saturated on hydrofluoric acid and calcium fluoride and returned to desorption of scandium. Sorption leaching of scandium-depleted pulp of rare-earth elements is performed with a cationite with a macroporous structure, containing sulphonic acid functional groups. Before desorption cationite is treated with sulphuric acid solution. Desorption of cationite is performed with ammonium sulphate solution, and concentrate of rare-earth elements is deposited with a saturated solution carbonate salt with similar cation.

EFFECT: high degree of extraction of scandium and rare-earth elements into end product with reduced costs for implementation of method.

7 cl, 1 dwg, 5 tbl, 5 ex