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Gassing in water based zinc baths

2003

We are looking for ways to decrease gassing of our Zinc rich water based coating bath. The Zinc protects the metal by galvanic action but when the zinc is in contact with water in the bath gassing (hydrogen evolution occurs) due to the zinc reacting with the water. This leads to blow out of tanks due to pressure build up. I am looking for suggestions as how to prevent the gassing in these baths.

Thank you,

Vignesh Palanivel
metallic coatings supplier - Cleveland, Ohio

Vignesh,

Surely the problem you have of gassing lies with your water being acidic and having a low pH.

Solution?

a. treat the water to 7 or so pH

b) use a pressure relief valve (try Plast-0-matic) on the tank(s).

Freeman Newton [deceased]
(It is our sad duty to advise that Freeman passed away
April 21, 2012. R.I.P. old friend).
2003