METHOD OF PROCESSING RARE-EARTH CONCENTRATE Russian patent published in 2016 - IPC C01F17/00 C22B59/00 C01F15/00 

FIELD: chemistry.

SUBSTANCE: invention can be applied for processing and deactivation of rare-earth concentrate (REC), extracted from apatite concentrate and products of its processing - phosphogypsum and extraction phosphoric acid. Rare-earth concentrate, extracted from raw material, which contains products of uranium-thorium series decay, are dissolved in nitric acid with heating and agitation of pulp, which is then diluted with water and cooled. After this, hydrogen peroxide with consumption which ensures 98.0-99.5% reduction of cerium (+4) to cerium (+3) is added. Then nitric acid solution of rare-earth elements (REE) is separated by means of filtration, from which thorium is separated in co-precipitation with barium sulphate by addition of sulphates and soluble barium compounds. Then neutralisation to pH 2.5-3.9 is carried out by mixing at temperature 35-45°C for 1.0-1.5 hours. Barium-thorium cake is separated by filtration.

EFFECT: invention makes it possible to simplify obtaining of deactivated REE oxides from products of apatite concentrate processing with reduction of expenditures.

2 cl, 3 tbl