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Gold Electro Chemical Deposition using Cyanide Solution

Hi everyone .. I need urgent help on this hope someone can help me out or point me to some quick online resources.

I need detail information regarding the ECD of gold using a solution of potassium gold cyanide, citric acid [on eBay or Amazon] and KOH.

I have been looking for the half equations for the cathode and anode reaction but didn't manage to find any. Hope someone can help me out of this.

Also, I would appreciate if someone could tell me the purpose of using of citric acid and KOH in this case.

Regards,
Sunny

Sunny Tay
Student - Singapore
2006

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I don't believe gold baths have both citric acid and KOH in them; I believe it's either/or: citric acid for acid gold cyanide or potassium hydroxide for alkaline gold cyanide. The citric acid both buffers the bath and complexes the base metals for deposition in a controlled manner; I believe the KOH is just for pH control.

Although the half equation at the cathode can be expressed as simply as Au+ e- --> Au 0, gold plating is actually quite complex, and you may want to consult Gold Plating Technology by Reid and Goldie to really understand the reactions.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2006

Try next web page www.pfonline.com/articles/079702.html (very good and short article on different gold plating baths). Good luck and hope it helps!

Goran Budija
- Cerovski vrh Croatia
2006