Heavy Metals Recovery from Electroplating ...

A combined processes of acid-leaching, electrodepositing and ammonium jarosite precipitating was developed to recover heavy metals from an electroplating sludge. More than 97% of copper, nickel, chromium, and 84% of iron were extracted from the sludge with 10% H2SO4 leaching. More than 99% of copper was recovered from the leaching solution with electrodepositing process. The left solution after copper recovery was then treated with ammonium jarosite precipitating process, about 99.9% of chromium and iron could be deposited as chromium ferrite in this process. Finally, the left solution was treated with electrodepositing process again for nickel recovery, and about 58% of nickel could be recovered in this process under the condition of pH 5.5 and voltage 5.5V.