Recent developments of electrodeposition-redox replacement in metal recovery and functional materials: A review

Review—Influence of Corrosion Reactions on the Pulse Electrodeposition of Metals and Alloys

“…41 Corrosion effects in the electrodeposition -redox replacement (EDRR) processes.-A useful variant of pulse plating where displacement and corrosion effects are both important is the electrodeposition-redox replacement (EDRR) process which has been developed for trace metal ion recovery. [66][67][68] In the EDRR process, a less noble component (e.g. Cu, Zn or Ni) is deposited on an electrode in the on-time, while in the off-time a noble metal (e.g.…”

“…This ensures that the resulting deposit contains predominantly the noble component, and this method has been shown to be competitive with other hydrometallurgical processes for extracting high-value metals from waste streams. 66 One potential complication with the EDRR process is corrosion of the less noble metal in the off-time, and this has been noted in a number of studies. [66][67][68] This is undesirable as it results in a loss of the less noble component and this reduces the amount of the nobler material that can be deposited by displacement in the off-time.…”

“…66 One potential complication with the EDRR process is corrosion of the less noble metal in the off-time, and this has been noted in a number of studies. [66][67][68] This is undesirable as it results in a loss of the less noble component and this reduces the amount of the nobler material that can be deposited by displacement in the off-time. For example, during the recovery of Ag by displacement on to a Zn layer from acidic solutions, corrosion of Zn in the off-time by H + ions was demonstrated to occur.…”

Recovery of Gold as Nanoparticles from Gold-Poor Au-Cu-Cl Solutions

“…A recently developed electrochemical method to recover noble metals from solutions with large differences in concentration is electrodeposition-redox replacement (EDRR) . In EDRR, a sacrificial layer is first electrodeposited (typically using a metal that is abundant in the solution), after which a spontaneous replacement reduction occurs between the dissolved noble metals (also present at low concentration) in the solution and the deposited layer.…”

“…A recently developed electrochemical method to recover noble metals from solutions with large differences in concentration is electrodeposition-redox replacement (EDRR). 26 In EDRR, a sacrificial layer is first electrodeposited (typically using a metal that is abundant in the solution), after which a spontaneous replacement reduction occurs between the dissolved noble metals (also present at low concentration) in the solution and the deposited layer. In a recent publication studying the EDRR method for copper and gold in chloride solutions, Korolev et al 27 noted that spontaneous corrosion of deposited copper (eq 1) was followed by an aqueous cementation reaction between the dissolved aurous and cuprous species (eq 2), resulting in additional gold deposition.…”