Silver Electrodeposition from Cyanide Solutions: Effect of Lead Ions

✍ Scribed by R. Yu. Bek; L. I. Shuraeva; S. N. Ovchinnikova

• Book ID: 111608239
• Publisher: SP MAIK Nauka/Interperiodica
• Year: 2004
• Tongue: English
• Weight: 77 KB
• Volume: 40
• Category: Article
• ISSN: 1023-1935
• DOI: 10.1023/b:ruel.0000046494.46311.5e

✦ Synopsis

Effect of lead hydroxy compounds on the process of electrodeposition of silver from cyanide electrolytes is studied on an electrode whose surface is renewed in solution by cutting off a thin layer of metal. This permitted to perform the study on both the freshly renewed electrode and at controlled values of the time of the electrode contact with solution ∆ t . Shown is that on the freshly renewed electrode ( ∆ t < 1 s) the presence in the solution of lead ions in concentrations Ò 1 on the order of 10 -5 M leads to the process depolarization only in the initial portion of a polarization curve. With Ò 1 increased to 10 -4 M the effect of depolarization extends on the entire polarization curve. Keeping the electrode in solution after the renewal of the metal surface magnifies depolarization, and the greater the concentration c 1 , the shorter the time period ∆ t required to achieve the same effect. These regularities are attributed to catalytic influence of lead adatoms, whose surface concentration depends on Ò 1 and ∆ t , as well as on the intensity of their incorporation in the silver deposit.