METHOD OF PREPARING HIGH-DISPERSITY AND GRANULOMETRICALLY UNIFORM RARE-EARTH ELEMENT CARBONATES WITH

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FIELD : nonferrous metallurgy. SUBSTANCE : invention relates to hydrometallurgy of rare-earth elements, in particular to technology of preparing of rare-earth element carbonates with controlled particular shape used in manufacture of polishing materials and catalysts. Suspension of rare-earth element carbonates prepared by mixing rare-earth element carbonate solution with carbonic acid solution is stirred at 20 to 75оС at suspension motion velocity between 0.5 and 20 m/s, whereupon rare-earth element carbonates are precipitate in plate form at stirring for a period of time satisfying relationship 1.5*T0.5 ≤ τ ≤ 30. Precipitation of dendritic carbonates is accomplished at stirring for a period of time satisfying relationship 106*T-2.5 ≤ τ ≤ 600, where τ are numeric values of stirring time, min, and T are numeric values of reaction medium temperature, оС. EFFECT : extended temperature range for precipitation of plate- and dendritic-form rare-earth element carbonates and improved granulometric uniformity of product. 2 dwg, 2 ex