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Carbon Anodes for Electrogalvanising

This is a theoretical type question :

Is there any reason why carbon is not used as the anode material for electrogalvanising? Carbon is stable, electrically conductive and can tolerate scratches (unlike the coated titanium DSA anodes) and has a (very!) low lead content.

I'm sure there is a reason, I just cannot think what it could be...

Yours in thought and meditation

Peter

Peter Levey
- South Africa
1998

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Most carbon anodes that I know consist of sintered graphite.

Anodic currents give rise to oxygen or chlorine gas evolutions and these gases cause disintegration of the sintered parts resulting in lots of fine graphite particles in your plating bath which are very hard to filter out; in the end your carbon anode will be eaten up completely , the higher the anodic current density the faster the destruction of the anodes.

Cesar A Boose
- ECA-Co
1997

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Commercial graphites forms sintered from compacts of graphite particles and binders would evolve the contaminants described by Cesar A. Boose. Instead, a pure graphite such as "ThermalGraph" from Amoco Performance Products in Alpharetta, GA would not do so. This graphite starts life as a refined pitch based precursor, with no additives, and is fired well above 2700C for graphitization. The thermal conductivity is higher than that of copper and the electrical conductivity is similar to that of titanium.

Check it out!

William De La Torre
- Research Opportunities, Inc.
1998

Hi,

I just realized there is this kind of anode called DSA. I'm just wondering where I can buy it. It would be great if anyone can give me the company name and phone #.

Sincerely,

Eric Wong
- McGill University
1999

There are a number of companies that provide anodes that fit the "DSA" type. DSA is a trademark. Also used are mixed metal oxide anodes. These anodes are ruthenium-titanium oxides for electrolysis of chlorides to manufacture chlorine, chlorate, and hypochlorite. For oxygen evolution (which is water electrolysis for electrogalvanizing applications) iridium-tantalum oxide mixes are used as the ruthenium has a shorter life.

Barry L. Martin
- Union, New Jersey
2003