METHOD OF PRODUCTION OF ANHYDROUS LITHIUM HYDROXIDE Russian patent published in 2005 - IPC

FIELD: chemical industry; methods of production of lithium hydroxide.

SUBSTANCE: the invention concerns technologies of production of A method of production of anhydrous lithium hydroxide used in chemical industry. The method of production of anhydrous lithium hydroxide provides for dissolution of the hydroxide, its physical and chemical purification on the mercury cathode from cations of alkali metals, sorption clearing from heavy metals, evaporation, filtration and drying on a steam screw-conveyor drier with a heated screw - dehumidifier. The lithium hydroxide drying is conducted in three stages. At the first stage the drying process is carried out at the temperature of 130-135°C and rarefaction of the air at an inlet in the dryer up to 10 mm of a water column within 30-33 hours till production of a product with a mass share of the base material of 69-73 %. At the second stage the drying process is conducted at the same parameters within 22-24 hours till production of a product with a mass share of the base material of 90-93 %. At the third stage process is conducted at the same parameters within 30-36 hours till production of a product with a mass share of the base material of no less than 98 %. The drying process at all its stages is carried out with a continuous reversible rotation of the screw - dehumidifier. The technical result is production of anhydrous lithium hydroxide with a mass of shares of the base material of no less than 98 % and a mass of ion carbonate shares of no more than 2 % at use of a simple equipment.

EFFECT: the invention ensures production of anhydrous lithium hydroxide with a mass of shares of the base material of no less than 98 % and a mass of ion carbonate shares of no more than 2 % at use of a simple equipment.

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