METHOD FOR PROCESSING OF OXIDE-NICKEL ELECTRODES Russian patent published in 2011 - IPC H01M10/54 

FIELD: electricity.

SUBSTANCE: invention relates to electrical engineering and may be used to manufacture components of active masses of positive electrodes of alkaline accumulators. According to invention, method for processing of oxide-nickel electrodes includes damage of electrodes, separation of metal component and active mass, leaching of nickel-containing component with solution of sulfuric acid with concentration of 28-32 wt %. Graphite is separated from solution of nickel sulfate by filtration and washed with water on filter. Produced washing solution is evaporated to concentration of nickel sulfate close to saturation. Both solutions, solution of nickel sulfate and washing solution, are cooled down to temperature of 10 - 20°C, are maintained at this temperature until sedimentation of crystals of nickel sulfate, which are separated from solution, mother solutions are combined and treated with concentrated aqueous solution of ammonia to produce main salts of nickel. Afterwards produced deposit is separated by filtration and is treated with solution of sodium hydroxide of 15-20%, to produce nickel hydroxide (II) and solution of sodium sulfate. Hydroxide of nickel (II) is filtered, deposit is washed with water and dried. Washing waters are added to solution of sodium sulfate. Ammonia released in production of nickel hydroxide (II) is absorbed by water and is returned for treatment of mother solution. Sodium hydroxide 15-20 wt % is added to solution left after separation of the main salts of nickel, until iron hydroxide (III) is deposited, which is filtered from solution of sodium sulfate. Produced solutions of sodium sulfate are combined, sodium sulfate is evaporated and crystallised.

EFFECT: improved efficiency of method for processing of oxide-nickel electrodes due to reduction of quantity of used water and reduction of volume of process solutions, increased purity of produced graphite.

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