PHOSPHOSEMIHYDRATE PROCESSING METHOD Russian patent published in 2014 - IPC C22B3/08 C22B59/00 

FIELD: metallurgy.

SUBSTANCE: invention refers to processing of freshly obtained phosphosemihydrate and can be used to obtain concentrate of rare-earth elements (REE) and gypsum product for construction materials. Phosphosemihydrate is processed with water solution containing fluorine-ion. Sulphuric acid leaching is performed with displacement and separation of the water solution containing fluorine-ion, as well as with conversion of REE and impurity components to a leaching solution and production of a phosphosemihydrate layer saturated with a sulphuric-acid solution. Then, water displacement of the remaining amount of sulphuric acid solution is performed so that washed phosphosemihydrate and a leaching solution is obtained Phosphosemihydrate is neutralised with a calcium-containing reagent so that a gypsum product is obtained. Rare-earth elements and impurity components are extracted from the leaching solution by sorption using sulphoxy cationite so that a lean sulphuric-acid solution is formed; REE and impurity components are desorbed from saturated cationite by its processing with an ammonium sulphate solution so that a strippant is obtained; REE and impurity components are deposited from the strippant with an ammonium-containing precipitator in two stages and REE deposit is separated.

EFFECT: method provides improvement of REE extraction efficiency.

6 cl, 4 ex