Effective removal of bismuth is a primary concern during copper electrorefining. A novel electrowinning process using an emew® cell was developed to recover bismuth and copper from a copper electrorefining waste stream. Significant removal and co-deposition of copper and bismuth were achieved from a highly acidic sulfate industrial effluent using a current density of 350 A m-2, but the current efficiency was low (27%). Operating at a lower current density (75 A m-2) facilitated the preferred removal of Cu, while increasing current efficiency to 67.4% due to the decrease of aside-reaction. Consequently, a two-stage process was employed to remove most of the copper at low current and then extract bismuth at high current. 93.4% of the bismuth and 97.8% of the copper were recovered with a satisfactory current efficiency, and a high purity (~98%) Bi powder was obtained in the second step. This novel emew® cell approach may serve as a promising alternative for recovering copper and bismuth, and the proposed two step strategy may offer insight for the selective recovery of metals in a multi-component system.
W. Jin et al., "Electrolytic Recovery of Bismuth and Copper as a Powder from Acidic Sulfate Effluents using an emew® Cell," RSC Advances, vol. 5, no. 62, pp. 50372-50378, Royal Society of Chemistry, Jun 2015.
The definitive version is available at http://dx.doi.org/10.1039/c5ra08318d
Materials Science and Engineering
Keywords and Phrases
Bismuth; Efficiency; Effluents; Metal recovery; Molecular biology; Powder metals; Recovery; Sewage; Copper electrorefining; Current efficiency; Effective removals; Electrolytic recovery; Industrial effluent; Multi-component systems; Selective recovery; Two-stage process
International Standard Serial Number (ISSN)
Article - Journal
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