화학공학소재연구정보센터
Journal of Power Sources, Vol.248, 596-603, 2014
Recovery of manganese and zinc via sequential precipitation from spent zinc-MnO2 dry cells after fusion with potassium hydrogenosulfate
This work describes a route for processing the electroactive components of spent zinc-MnO2 dry cells via fusion with potassium hydrogenosulfate (KHSO4). The fused mass was dissolved in water. Lead remained in the insoluble matter. Soluble zinc and manganese were isolated by a two-step precipitation procedure. Zinc was precipitated as oxalate after addition of aqueous H2C2O4 at pH around 1. Manganese was isolated as MnO(OH)(2) after adjusting pH at 11 using aqueous KOH + H2O2. pH control is essential for a successful separation of the elements. Both were recovered in high yields (>92 wt.%). About 75 wt.% of potassium was recovered as K2SO4 after treatment of the final effluent with sulfuric acid (pH 7) followed by slow evaporation. (C) 2013 Elsevier B.V. All rights reserved.