METHOD OF PRODUCING HIGHLY PURE HEXAHYDRATE OF MANGANESE NITRATE Russian patent published in 2011 - IPC C01G45/08 

FIELD: chemistry.

SUBSTANCE: method of producing hexahydrate of manganese nitrate involves dissolving manganese metal in a nitric acid solution, filtration, separation of the precipitate of impurities, evaporation of the solution to concentration 56-57% and crystallisation from the concentrated solution by cooling. Before dissolving, manganese metal is crushed to particle size 2.0-5.0 mm and leached with diluted chemically clean nitric acid and then filtered. The obtained manganese nitrate solution is purified from impurities by adding ammonium carbonate and an aqueous solution of ammonia to bring pH to 6.5-6.7. The suspension of crystalline precipitate obtained after crystallisation is held at final crystallisation temperature while stirring constantly for 15-45 minutes. The precipitate of the hexahydrate of manganese nitrate is then separated and washed with a saturated solution of pure manganese nitrate at temperature equal to final crystallisation temperature.

EFFECT: high purity of hexahydrate of manganese nitrate and improved electrical characteristics of solid-electrolyte capacitors made using said hexahydrate of manganese nitrate.

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