METHOD OF EXTRACTION OF SCANDIUM FROM SILICON-CONTAINING MATERIALS Russian patent published in 1997 - IPC

FIELD: hydrometallurgy of rare metals. SUBSTANCE: method involves grinding and decomposition of the parent material with sulfuric acid (concentration is 150-500 g/l) at 85-110 C followed by phase separation. Scandium-containing filtrate and solid silicon-containing deposit were obtained. Grinding is carried out up to obtaining particles of an average size 1-10 mcm. After grinding the parent material is placed in reactor containing preliminary heated sulfuric acid solution. Decomposition is carried out mainly at ratio solid phase : liquid phase = (1:4)-(1:7) for 1-6 h. To decrease scandium loss the deposit after filtration is washed off with water or diluted with HCl solution at ratio solid phase : liquid phase = (1:3)-(1:5), at 20-50 C. Method can be used for extraction of scandium from different silicon-containing materials. EFFECT: improved method of extraction, decreased scandium loss. 4 cl