Enhanced extraction of manganese from electrolytic manganese residue by electrochemical

High-valent manganese was hard to be extracted from electrolytic manganese residues. To strengthen the-extraction of Mn, electrochemical extraction method was investigated in this work. The mechanisms of the electrochemical extraction were examined along with the electrochemical performance of the reaction system via X-ray diffraction, scanning electron microscopy, X-ray Fluorescence, and BET. Results show that high-valent manganese can be reduced effectively under an electric field. The extraction efficiency of manganese reached 96.2% under the optimum conditions of current density 25 mA/cm(2), 92 wt% H2SO4, solid-to-liquid ratio of 1:5, room temperature, 1:1.0 M ratio of Mn to Fe2+ and 60 min extraction. The extraction efficiency of manganese is 51.8% higher than that attained under the same conditions without an electric field and Fe2+. Meanwhile, the manganese content in residue decreased from 234% to 0.09%. (C) 2016 Elsevier B.V. All rights reserved.