METHOD OF PROCESSING OF LAPARITE CONCENTRATE

• Main Authors: SHESTAKOV S.V, ZOTS N.V
• Format: Patent
• Language: English; Russian
• Published: 27.07.2001
• Edition: 7
• Subjects: CHEMISTRY; CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION ORPROCESSING OF GOODS; FERROUS OR NON-FERROUS ALLOYS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; METALLURGY; PRETREATMENT OF RAW MATERIALS; PRODUCTION AND REFINING OF METALS; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE; TREATMENT OF ALLOYS OR NON-FERROUS METALS

metallurgy. SUBSTANCE: method consists in grinding of laparite concentrate to particles sizing, at least, 0.075 mm with classification; breaking down of laparite concentrate with weak 47-55% nitric acid at temperature of 115-118 C and continuous moving of pulp through row of successively joined reactor vessels. Hydrate cake of refractory metal oxides obtained by breaking down of laparite concentrate is washed off with water to produce pure hydrate cake and active combined nitrate solution of rare- earth elements with impurities. Said solution is neutralized and deactivated with precipitation of all impurities including thorium and mesothorium. Pure nitrate solution of rare-earth elements is treated with sodium carbonate and sum of carbonates of rare-earth elements is precipitated. Filtrate is concentrated by evaporation to concentration of 500-600 g/l and subjected to hydrolysis at temperature of 600-800 C to produce elementary nitrogen, oxygen, carbon dioxide in exit gases and also sodium carbonate. The latter is directed for neutralization of nitrate solution and precipitation of carbonates of rare-earth elements. Exit gases are subjected to scrubbing with water and discharged to atmosphere. EFFECT: reduced expenditures and cost of product. 1 ex