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Contaminated Watts Nickel Bath, Please Help!

May 27, 2009

Hello out there,

We are nickel plating with a standard Watts formula. We were having the finish come out peeling and found out that last week when an employee was told to add a fixed amount (1800 grams) of boric acid, he mistakenly added trisodium phosphate ⇦this on eBay or Amazon [affil links] because the bags looked the same and the guy is an idiot. We have over 1000 gallons made up that we have been using for years and it is much too expensive and not the time to replace with a new bath. Is there any way this bath can be saved? Any advise is greatly appreciated, our production has ceased!

Thank you

Greg Johnson
Plating shop employee - Elk Grove, California

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First of two simultaneous responses --

I have never heard of a way to remove or kill it.
So, why do you employ an idiot? Why was an untrained person allowed to make additions to a tank?

James Watts
- Navarre, Florida
May 28, 2009

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Second of two simultaneous responses --

You could try HCD dummying.

J. Ott
plating - Middletown, Pennsylvania
May 29, 2009

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I have never had to do this, but I believe you can remove phosphate ions by adding an equivalent amount of iron perchlorate together with nickel carbonate and sometimes some sodium hydroxide, whilst thoroughly stirring the solution. The pH should be adjusted to about 5-5.5 and the solution filtered. I also believe that nickel phosphate is precipitated at pH's in excess of 6. You will need to rebalance your solution and this will not be an easy and quick fix.
Before doing the full scale bath, I suggest you try this recovery process on a beaker scale first!
I would also suggest you segregate your chemicals a but better, but this won't help you now! Is it possible for you to store all the chemicals for any one bath in the same place, so there is no risk of cross contamination?

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
May 30, 2009

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First of two simultaneous responses --

I'm not certain 1800 grams of TSP in a thousand gallon nickel bath will cause any problem at all. Have you adjusted pH and eliminated all other possible causes of your problem?

Jeffrey Holmes, CEF
Spartanburg, South Carolina
June 2, 2009

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Second of two simultaneous responses -- June 3, 2009

No way you can decontaminate this bath.
Throw it away together with your employee

Sara Michaeli
Tel-Aviv-Yafo, Israel

In first 1800 grams of boric acid do not impact 1000 gallons of nickel bath, and Trisodium Phosphate is not a serious contaminant for Watts nickel bath, try out with a new nickel bath and add drops of a solution of TSP while making a Hull cell, and you will understand that you must search other cause for "plate peeling".

Franz Robert Wagner
- Blumenau SC Brazil
June 8, 2009