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Removing zinc from a mixed chloride solution

I am trying to remove the zinc from a discarded mixed chloride zinc solution by raising the PH to 10 with liquid sodium hydroxide.The best I can achieve is 350 ppm.I assume the ammonia ⇦ this on eBay or Amazon [affil links] is complexing the zinc. Any suggestions?

Ian Lawson
Technical Manager - Brisbane, Queensland, Australia
August 6, 2010

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August 12, 2010

Hi,

You do not write anything about concentrations of all considerable components neither what treatment-results you really like to achieve. A little bit more info would be greatly welcomed.

Cheers

Dominik Michalek
- Sydney, Australia

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August 12, 2010

You are probably on the right track to reduce the zinc as much as possible by pH adjustment. The remaining zinc can be precipitated with a chelate breaker such as a carbamate.

Lyle Kirman

Lyle Kirman
consultant - Cleveland Heights, Ohio

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August 12, 2010

Dominick,
Zinc is 47 g/L and total chloride is 156 g/L. Ammonium chloride has been analysed as 49 g/L and potassium chloride 160 g/L. I would like to drop the zinc to 10 ppm or lower if possible.

Regards
Ian

Ian lawson
- Brisbane, Queensland, Australia

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August 15, 2010

Lyle,
As I have never used a carbamate to precipitate zinc before how much would you suggest I use.
Regards,
Ian.

Ian Lawson
- Brisbane, Queensland, Australia

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August 17, 2010

Hi Ian,

its quite a lot of metal available which requires an huge chemical demand to precipitate the zinc which will also cause then a quite big amount of sludge which will bring then higher disposal costs. In my opinion an electrodeposition (recycling of zinc metal) would be the best what can be done, depends on concentration which you will get then proceed with normal treatment/neutralisation and if required adding a compatible flocculation agent, you should reach then the required max.-allowance level or lower.

Good Luck!

Regards,
Dominik

Dominik Michalek
- Melbourne, Australia