The Initial Process of Recycling Waste Mn-Zn Batteries through Synthesizing Mn -Zn Ferrite

This paper describes the dissolving process of recycling waste batteries through synthesizing Mn-Zn ferrite by using mixed acid and water as leaching solution and oxalic acid as reductant. Some factors were investigated that include the proportion of mixed acid and its dosage, liquid-solid ratio, dosage of reductant time and temperature. Results show that an excellent dissolving effectiveness was gotten when the leaching solution composed of mixed acid (HNO₃/HCl = 1:3-1:4 V/V) which was 0-20% in excess and oxalic acid which was 10-20% in excess at a condition that the temperature was under 40°C, liquid/solid ratio was about 4.6, the time for first leaching step was longer than 10h and second leaching step was 1 hour. The recovery ratios of Mn, Zn, Fe, Ni, Cu and Hg were about 99%, even up to 100%, and the residue had a very low mercury content level.