METHOD OF PRODUCING HIGHLY PURE ALUMINIUM OXIDE BY ELECTROLYSIS Russian patent published in 2015 - IPC C01F7/42 C25B1/00 

FIELD: chemistry.

SUBSTANCE: hydroxyl precipitate is separated using three vertical sieves, having opening diameter of: 3-4 mm, 1-2 mm, 0.1-0.5 mm, respectively; the filtered precipitate is subjected to two-step washing with solid to liquid ratio of 1:2-10 at 5-95°C. The washed precipitate is dried at 340-700°C and calcined to obtain aluminium oxide, which is then mixed with distilled water with solid to liquid ratio of 1:3-12 to form a pulp, which is then stirred for 20-120 minutes at a rate of 200-1200 rpm at 5-95°C; after mixing, the aluminium oxide is filtered from the mother solution and dried at 100-300°C.

EFFECT: invention enables to obtain highly pure aluminium oxide with high content of basic component.

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