Electrodeposition cyanide copper

Dudek, D.A. and Fedkiw, P.S. (1999) Electrodeposition of copper from cuprous cyanide electrolyte I. Current distribution on a stationary disk. / Electroanal. Chem., 474 (1), 16—30. 

Study of the influence of the polyalcohol sorbitol on the electrodeposition of copper-zinc films from a non-cyanide bath. /. Electroanal. Chem., 562 (2), 153-159. 

Copper is electrodeposited commercially mainly from cyanide, sulphate and pyrophosphate baths. For rapid deposition in electro-forming, a fluoborate bath may also be used. 

This leads us to the discussion of the methods by which the throwing power can be increased. Increasing the conductivity of the solution is an obvious approach, but is limited in scope. A specific resistivity of 5 ii cm, found it the case of the so-called acid copper bath, which contains CuSO and H SO, is about as low as one can get in aqueous solutions. The other approach is to decrease i. The kinetics of metal deposition from tlie simple ions is usually fast, but when the ion is complexed, much lower values of the exchange current density can be realized. This is one of the reasons for using cyanide baths for the electrodeposition of many metals. Copper, for example, can be deposited from an alkaline bath containing KCN. Instead of the usual aquo-complex [Cu(H O) ] one has the much more stable (K = 5.6x10 ) cyanide... 

The elements are widely distributed in Nature in the free state and in sulfides and arsenides silver also occurs as the chloride, AgCl. Silver is often recovered from the work-up of copper and lead ores. The elements are usually extracted by treatment with cyanide solutions in presence of air and are recovered from them by addition of zinc. They are purified by electrodeposition. 

Bozzini, B., D Urzo, L., Mele, C. and Romanello, V. (2008) A SERS investigation of cyanide adsorption and reactivity during the electrodeposition of gold, silver, and copper from aqueous cyanocomplexes solutions. The Journal of Physical Chemistry C, 112, 6352-6358. 

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