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Ammonia in Watts Nickel Plating Bath

 

Our company uses a Watts nickel plating bath and we send our F006 waste out for metals reclamation. Our last shipment was rejected due to an ammonia ⇦ this on eBay or Amazon [affil links] concentration of 200 ppm. We sent out a sample of our nickel bath for analysis and sure enough the concentration of ammonia was 200 ppm. What could the source of the ammonia be? Our plating supplier doesn't know where it could be coming from and I don't think it would be from the brighteners, myself.

Thanks,

Chris Ballew
- Newport, Tennessee

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Chris, In nickel sulfamate baths, ammonia is a product of having too low of a pH (<3) and operating at high temperatures (>70° C) for long periods of time. Due to this conditions, the nickel sulfamate ion is hydrolized forming nickel ammonium sulphate. In our case, we have seen ammonia concentrations up to 2.5g/L before new bath formulations. Good Luck! Ernesto Rodas - Chicopee, Massachusetts Hi Chris, How much ammonia have you used in analysis since start-up time which has been poured back into your zero-discharge recycle system. All that analysis ammonia would complex as Nickel Ammonium sulphate and be there forever especially in a zero-drag-out due to zero discharge - it would just accumulate and accumulate until someday it would reach 200 ppm. Also how are they analysing for ammonia, the only way to get it out of Nickel ammonium sulphate is to use a MicroKehldal whereby the sample is first alkalized in a closed system and then distilled. I would seriously question the 200 ppm analysis. I feel sure they have detected qualitatively the presence of ammonia, but doubt they have accurately measured the quantity. I know who can do it right for you. Call me. Robert H Probert Robert H Probert Technical Services Garner, North Carolina

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1. You have sulphate not sulfamate so the first message does not apply to you.

2. I thought of something else. Do you use or have you ever used a so called proprietary "acid salt". Many of those formulations use Ammonium BiFluoride or Sodium BiFluoride, which again as I said in the above message, drags down the line and complexes with the nickel to form Nickel Ammonium sulphate.

Robert H Probert
Robert H Probert Technical Services

Garner, North Carolina

 

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November 3, 2008

Following the thread of the question... I was just wondering whether it is possible to get rid of ammonia contamination from a Sulfamate Nickel Bath or not. It is believed that it is not possible to do so. Is that true?
Kind Regards,
Jose

Jose V. Morales
- Madrid, Spain