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Decreasing Copper Content of our Descaler Solution(Pre-treatment)

We are currently using a descale that etched copper
of our strips on a very fast phase. Is there any
other way that can we lessen the copper content of our descale
through the use of special catalyst or some kind
of corrugating technique to at least prolong the bath life and
efficiency of our solution?

Charlie dela Cruz
Electroplating - Muntinlupa, Philippines
2006

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Depending on what the descaler/etcher is, and what temperature it operates at, it may be possible to simply cool it and have some of the copper salt precipitate out. This has been done on a continuous basis for sulfuric acid - hydrogen peroxide etchants.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2006

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Your descaling/etching bath formulation should have some inhibitors to prevent excessive attack on the copper strips. Azole group compounds, such as benzotriazole ⇦ this on eBay or Amazon [affil links] (BTA), mercaptobenzothiazole (MBT), etc. are well known for their ability to prevent corrosion of copper alloys.

You can try to galvanically plate the copper over steel, provided the iron content in the bath will not affect the performance and efficiency of your process.

T.S.N. Sankara Narayanan
- Chennai, Tamilnadu, India
(ed.note: The good doctor offers a fascinating blog, "Advancement in Science" )
2006

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2006

Our descaler is a salt-based solution operating at 35 degC.
The bath life usually last for a week only due to effect of copper content in the solution that results some visual problem which we don't experience when copper content is low.

Can you give us some other inputs on what can we still do to improve in such condition?

By the way, thanks for the info earlier.

Charlie dela Cruz
manufacturing - Philippines

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Please give the descaler solution composition and the subsequent operation. Why does the copper have scale in the first place, maybe from annealing in air? Perhaps scale formation can be avoided.

Any results for the inhibitor, plate out and precipitation suggestions in letter 39488 (www.finishing.com/394/88.shtml)?

Ken Vlach [deceased]
- Goleta, California
Finishing.com honored Ken for his countless carefully researched responses. He passed away May 14, 2015.
Rest in peace, Ken. Thank you for your hard work which the finishing world, and we at finishing.com, continue to benefit from.
2006