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Ion-exchange resin for electroplating rinses

1999

We are interested in finding an ion-exchange resin system that we can use on a acid barrel zinc plating rinse. We need to remove the zinc ions from the water but we do not want to remove the calcium or magnesium or any other ion within the water if at all possible.

The rinse is at pH 5.0 - 5.5. What we need to know is this: -

1. Is a resin available to do this task?

2. Is there a cheap resin that can be used as a disposable item (i.e. discarded with contaminant rather than be re-generated)?

Please give guidance about any UK source for any suitable resins. Many thanks.

David Grimes
plating company - Farnham, Surrey, United Kingdom

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1999

Hi David , The best people that I know regarding Ion - Exchange are as follows :

ResinTech Inc
1980 Old Cuthbert Rd
Cherry Hill New Jersey
I feel sure they have a product to fulfill your needs. Best regards,

John Tenison - Woods
- Victoria Australia

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The kind of selectivity you're looking for might be found in a phosphonic acid type resin, such as Duolite ES-63. This is said to have a special affinity for zinc and other transition elements, though you must do a column study to be sure. There are numerous adsorbants available, often clay or zeolite minerals, that are geared to be disposed when exhausted; I'm not sure that they are selective. In any case, the capacity is liable to be such that you would have a large volume of waste to be disposed of, probably in a haz waste landfill.

Dave Wichern
Consultant - The Bronx, New York
1999

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Mr. Grimes: We obviously rarely find a product that meets every parameter on our wish list, and I don't think you will find a resin that will allow you to practically remove zinc selectively. But Mssrs. Tenison-Woods and Wichern may be familiar with something that I'm not. Regarding disposable ion exchange media, you could try some lit study on insoluble starch xanthate.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
1999

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My reaction is kind of late and maybe you have found a solution yet.

There is a resin that is selective for zinc and will not adsorb calcium, magnesium or sodium. It operates in the pH-range you have specified. The unique properties of this resin involve another way of complexing. The zinc-ion is not exchanged, but a complete zinc-salt molecule. This also means that no other ions will enter the rinse solution and the conductivity will be reduced as well.

The resin is being produced in the US and Recomet represents the producer within European countries. Please contact us in case you are interested and we will forward you additional information.

Ruud Gerritsen
- Simpelveld, Netherlands
2000

We are producing high ion exchange resin for many application, including selective removal of certain heavy metals such as zinc.

Erinaldi
Bayer Indonesia - Jakarta, Indonesia
2001

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Dear,

I would like to know the detail and application of Duolite resin ES-861.

Thank you,

Siripong Premjet
- Muang, Phitsanulok, Thailand
2001

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1. I note Ltr.No. 3291. Are there so many letters exchanged on the subject?

2. I have worked in both domains: metal finishing and Ion Exchange for separation, purification and recycling.

3. I would be interested to know if an answer has been found, tested in practice and deemed suitable both technically and economically

RAUL RAITER
- PERTH, AUSTRALIA
2005

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Regarding your point 3: Well put, Mr. Raiter. I understood that that was the question on the table from the beginning, but it remains unanswered. If one of the companies who have talked about the "availability" of resins will instead point us to a published technical article in a peer reviewed journal, then we will have made great progress. I hope such an installation exists, but so far I have not seen anything that would lead me to be hopeful. Regards.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2005