Electrolytic Copper Deposition from Ammoniacal Alkaline Solution Containing Cu(I)

Abstract

In order to verify the feasibility of copper electrodeposition from ammoniacal alkaline solutions containing Cu(I), the cathodic polarization characteristics of Cu(I) and the galvanostatic electrodeposition from a Cu(I) solution were investigated. The cathodic polarization curve for the 0.5 kmol m À3 Cu(I)-5 kmol m À3 NH 3 -1 kmol m À3 (NH 4 ) 2 SO 4 solution showed an increase in the electric current corresponding to the deposition of copper at around À0:22 V vs. SHE which is much higher than the potential for hydrogen evolution. The current efficiencies for the copper electrodeposition from the Cu(I) solution nominally without Cu(II) were greater than 95% in the current density range of 200 to 1000 A m À2 . A further increase in the current density resulted in a decreased current efficiency due to the hydrogen evolution. The current efficiency decreased with the increasing Cu(II) concentration and temperature. These results indicate that the present copper electrodeposition method is applicable for the new energy-saving hydrometallurgical recycling process.

Hydrometallurgical process for the recycling of copper using anodic oxidation of cuprous ammine complexes and flow-through electrolysis

“…In order to take advantage of this, however, both the low overpotential and high current efficiency are desired for both the cathode and anode reactions. On the one hand, we and some other researchers have reported a high current efficiency and low overpotential as for copper electrodeposition from Cu(I) in ammoniacal solutions [4][5][6]12,13]. On the other hand, a literature search showed that little attention has been given to the anodic oxidation of Cu(I).…”

“…Although copper could be recovered from these wastes in a pyrometallurgical process [1,2], a hydrometallurgical process has certain advantages such that the capital cost is generally lower than a pyrometallurgical process and that it could be economically operated even on a small scale. Our research group has been studying a hydrometallurgical copper recycling process for PCBs [3][4][5][6][7][8]. In this process, copper in the waste is dissolved as cuprous ammine complexes (Cu(I)) using a solution containing ammonia, an ammonium salt, and cupric ammine complexes (Cu(II)) [3], and metallic copper is then electrowon from the Cu(I) [4][5][6] after removing impurities from the solution [7].…”

The ammonia leaching of alloy produced from waste printed circuit boards smelting process

“…In the ammonia leaching for copper, cupric (Cu 2þ ) amine could be used as oxidant, and the complex ions are able to be reused by electrical oxidation Koyama, Tanaka, Miyasaka, & Lee, 2006;Oishi, Koyama, Konishi, Tanaka, & Lee, 2007;Oishi, Yaguchi, Koyama, Tanaka, & Lee, 2008a, 2008b. Ammonia leaching processes have been developed and investigated to recover valuable metals such as copper, gold, silver, cobalt, and nickel (Yoo & Kim, 2012).…”

Application of Ammoniacal Solutions for Leaching and Electrochemical Dissolution of Metals from Alloys Produced from Low-Grade E-Scrap

“…nickel, zinc) in carbonate, sulfate, chloride baths [9][10][11] or gold and silver in thiosulfate baths [12][13][14]. High purity copper was then recovered by electrowinning from Cu(I) or Cu(II) ammoniacal baths [15][16][17].…”