ISSN 1017-2548(Print)
ISSN 2234-8530(Online)
Volume 17, Number 4
JKCSEZ 17(4)
August 20, 1973 

With the intention of obtaining technical data for the industrial production of γ-MnO2 for dry cell depolarizer by electrolytic oxidation of acidic manganese sulfate solution made from domestic rhodochrosite, optimum conditions of ore leaching, purification of leached solution and electrolytic oxidation of divalent manganes to tetravalent were investigated using simulated micro pilot plant having a production capacity of 4 kg of MnO2 per day. The nature and quality of the products were investigated by means of chemical analysis, DTA, X-ray diffraction and electron microscopy. The cell activity of MnO2were examined by cell discharging character measurements. The optimum electrolysis conditions were as follow: Temperature of the electrolyte, above 90℃; current density, 0.7~1 A/dm2; anode materials, graphite or lead ; concentration of electrolyte, MnSO4 50~150 g/l and H2SO4/MnSO4 = 0.15~0.25. Under the best condition the current efficiency was 99% and the products were almost pure γ-MnO2. The cell discharging character were good and almost the same as that of regular grade commercial electrolytic manganese dioxide.