METHOD OF PROCESSING LOPARIT CONCENTRATE Russian patent published in 2001 - IPC

FIELD: hydrometallurgical processing ore concentrates, mainly loparit concentrate. SUBSTANCE: proposed method includes grinding the concentrate to size of particles of at least 0.075 mm, stripping of loparit concentrate with nitric acid at atmospheric pressure and temperature above 100 C obtaining hydrate cake of refractory metals and nitrate solution of rare-earth elements and filtration of hydrate cake followed by processing of products thus obtained. Stripping is performed at initial concentration of nitric acid in pulp from 350 to 500 g/l temperature of 105 to 110 to C presence of catalyzing additives made from fluorine-containing compounds in the amount of 0.1 to 7.5% of mass of concentrate per fluorine ion. HF, NH₄F, NH₄HF₂, NaF, CaF₂ and their mixture are used as fluorine-containing compounds. EFFECT: low coat of finished product; enhanced economical efficiency of process. 2 cl, 1 tbl, 1 ex