Copper plating: Anode consumption Q&A's

A. I do not plate copper, but I would never cover a titanium basket with stainless steel.
I do not like dissimilar metals. You have Ti, SS, and Cu. It will be a confused battery.
If you are going to use Ti baskets, why not use a fine Ti mesh or very small expanded Ti?

I thought that plain steel was normally used for alkaline baths.

You do not mention your carbonate level.

My text books say that you should be using OFHC copper for anode material.

A. ANODES POLARISED:- LACK OF FREE CYANIDE
ANODES BLACK:- METALLIC CONTAMINATION (LEAD) DUMMYING AT 1 A/DM SQ.

A. I think you are not using the correct anodes for your cyanide copper electrolyte. You have to use "electrolytic copper anode" specially designed for cyanide copper. If you use "phosphorous copper anode", designed for acid copper electrolyte, you will have this black/brown deposit on your anodes ;)

Hi Lijo. Although I'm a little bit unsure about whether you are electrodepositing copper onto some other metal or are electrodepositing some other metal onto copper, the basic situation is the same. There are two different calculation approaches, and you can use each to serve as a check on the other:

1). Plating tanks can run for years in a state of approximate equilibrium, which means that the amount of anode consumed equals the amount of metal deposited onto the parts, otherwise the bath would either quickly build up in metal or starve. So just calculate how much metal you put on your parts, and that's how much metal you'll use in your anodes.

2). Faraday's Law says that the electrons you move from the anode to the cathode through your rectifier force an equivalent number of atoms to oxidize & dissolve at the anode and be reduced onto the cathode. 96485 ampere-seconds moves one equivalent weight. So 30 minutes @ 50 A = 90000 ampere-seconds, which moves about .93 equivalent weights. Give us the plating solution you are using and we can estimate the weight of metal you are electrodepositing and dissolving from the anodes.

Regards,

Dear Sir,
I am very much delighted and thankful for your advice. Furthermore we are electroplating another metal onto copper to prevent corrosion of copper bars in electrical panels.
We apply only a thin layer of plating on copper bars and plating thickness is approximately 5-7 microns. Hence I am unsure about your first opinion. In 2014 our copper consumption is 50,502KGS whereas our anode consumption is only 500KGS.
Since we have copper strips of various length I would like to get an idea of how much anode required to plate one m2 of copper area so that I can use for various sizes.
Once again thanks for your time and efforts for the industry,
Regards,
Lijo

Hello again, Lijo. It's very hard to proceed in the abstract. If we don't know whether you are electrodepositing silver, or tin, or something else, and whether it's an acid or alkali bath, we can't give you the atomic weight or the oxidation state or the density factors you would need to proceed with a Faraday's Law calculation. All we can tell you in the abstract, once again, is that you'll deposit .93 equivalent weights of that metal if you plate for 30 minutes @ 50 A.

Likewise, if you know the total surface area of the parts you plate, and you know the thickness, you can calculate the volume of metal plated onto the cathode and dissolved off the anodes, but you can't calculate the weight until you know what metal you are plating, and its density.

A general rule of thumb for a lot of types of plating is that you should have about twice as much surface area in the anode as the cathode. If you are doing silver plating, yes, you must track the anode usage; it's not fair to you or your employees to have such a valuable material go missing without proper accounting.

Regards,