METHOD FOR BIFLUORIDE TREATMENT OF RARE AND RARE-EARTH MINERAL MATERIAL Russian patent published in 2016 - IPC C22B34/14 C22B59/00 C22B1/00 C22B3/04 

FIELD: chemistry.

SUBSTANCE: invention can be used at ore-processing enterprises for breaking up and processing hard-to-decompose concentrates for extraction of rare-earth metals, zirconium, titanium and other metals. A method for bifluoride treatment of especially hard rare and rare-earth mineral material includes mixing raw material in powder form with a solid fluorinating agent and treatment in fluoroplastic reactors with a closed-type steel cover at 140-190°C and excess pressure. As the fluorinating agent a mixture of ammonium bifluoride (hydrodifluoride) (NH₄HF₂) and hydrofluoric acid in an amount sufficient for complete absorption of the released ammonia is used.

EFFECT: providing a method for bifluoride decomposition of concentrates of rare-earth metals and hard rare metal concentrates, including concentrates containing rare-earth metals, which enables concentration of rare-earth metals in the form of insoluble fluorides and further conversion thereof into a convenient soluble form.

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