METHOD FOR PREPARING LIGHT GRADES OF PURE MAGNESIA FROM SERPENTINITE Russian patent published in 2005 - IPC

FIELD: chemical industry, inorganic chemistry, chemical technology.

SUBSTANCE: invention relates to methods for preparing magnesia light grades from serpentinite. Method for preparing pure magnesia light grades from serpentinite involves its dissolving in sulfuric acid, cooling the prepared mixture up to crystallization temperature, washing out the crystallized mixture with water, separation of undissolved residue from prepared sulfate solution followed by successive treatment of prepared filtrate from metal impurities by their precipitation as hydroxides, separation of precipitate, treatment of prepared solution with alkaline reagent, separation of magnesium-containing precipitate, washing out precipitate with water and thermal treatment. In precipitation of magnesium-containing compound from sulfate solution previously purified from metal impurities method involves using 7-15% caustic soda solution and magnesium-containing compound precipitate is steamed out in boiling solution for 15-30 min up to the complete decomposition of soluble magnesium hydrocarbonates. Invention provides solving the problem for preparing light grades of pure magnesia from raw containing silicon oxides by economy and ecologically pure method.

EFFECT: improved preparing method.

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