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FIELD : chemical technology, production of rear earth element compounds, in particular production of polishing material for optical glass treatment.
SUBSTANCE : claimed method includes fluorination of rear earth element carbonates and calcinations of fluorinated carbonates. Rear earth element carbonates are prepared by deposition from rear earth element chloride solution with sodium carbonate solution on previously prepared crystallizing grains such as seeding agent obtained by deposition from rear earth element chloride solution having concentration of 60-70 g/l with sodium carbonate solution having concentration of 60-70 g/l at 20-25°C, solution pH 4.6-4.9 for 1-1.5 hour. Deposited carbonates are washed. Method of present invention makes it possible to obtain fluorine-containing polishing material with particle size of 0.8-1.0 mum.
EFFECT : improved material useful in polishing of precise optic materials.
2 cl, 1 tbl, 1 ex