Carlo Adamoli
Process for the extration of bases of rare elements contained in ores and rocks
Pagina 15
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7. In a cyclic process for obtaining beryllium hydrate from silicated minerals containing a relatively small proportion of beryllium, the steps consisting of crushing the mineral, mixing it in a paste with calcium fluoride and an aqueous solution containing nitric acid and a water soluble alkali-metal nitrate, heating said paste at a low temperature to form calcium nitrate, expelling from the paste the liquid containing the .calcium nitrate and alkali-metal nitrate, briquet-ting the paste and heating it to a high temperature to form a water soluble fluorine compound of beryllium, lixiviating the reaction product, separating therefrom a solution containing the fluorine compound of beryllium and at least a part of the initial alkali-metal nitrate, electrolyzing said solution to precipitate beryllium hydrate, separating said precipitate, mixing the solution from the electrolier and which contains fluorinated and nitrated alkali-metal salts with the solution containing calcium nitrate and alkali-metal nitrate expelled from said paste to precipitate calcium fluoride and form a solution of alkali-metal nitrate, reacting a portion of said solution of alkali-metal nitrate with hydrochloric acid to form a solution containing alkali-metal chloride, alkali-metal nitrate and nitric acid, separating the alkali-metal chloride from said last mentioned s solution and utilizing it in the electrolyzer for a fresh operation of precipitating beryllium hydrate, converting the chlorine given off in the electrolyzer into hydrochloric acid and using the hydrochloric acid to treat another portion of alkali-metal nitrate solution, and returning to the cycle the precipitated calcium fluoride, the nitric acid and also the alkali-metal nitrate not reacted with hydrochloric acid.
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