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Waste water treatment for complex cyanides

I want to know, how, after chlorination of cyanide wastes, the presence of complex cyanides (like Nickel/copper cyanide) is analyzed? How complex cyanides are treated, if they are not treatable by chlorination?

Regards.

Shevade Sudhanshu
Industrialist - Aurangabad, Maharashtra, India
2003

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2003

Mr Shevade,

Prevention is usually prescribed in such cases.

How does Nickel get into the copper waste water stream in the first place ?

Segregate the two streams. Treat Ni bearing waste water separately.
Teat the copper cyanide water separately.

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Then we have what is called abatement. PP = Pollution Prevention .
Replace the cyanide copper if it is simply a strike on steel and replace with Woods Nickel and say goodbye to cyanide,

If you are doing Zinc Diecastings , well a Non Cyanide copper is available from suppliers. It is a skilled job to run it.Not so simple like cyanide copper.

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Cyanide is on the way out and people like you can help spread the example .

Regards

Asif Nurie [deceased]
- New Delhi, India
With deep regret we sadly advise that Asif passed away on Jan 24, 2016

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Mr. Nurie gave sound advice on avoiding cyanide use if possible. However, your present cyanide destruct procedures may need some improvement. Both Cu and Ni cyanides can be destroyed by oxidation at pH 11, and resulting cyanates should be destroyed by further oxidation at pH 8-8.5. If pH's are correct, longer reaction times or high ORP's may be needed. There is conflicting data as to whether Cu & Ni require separation; some authors claim Cu is a catalyst for cyanide destruction. Iron is one common metal that forms a difficult-to-treat cyanide complex.

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.
2003

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Thanks to Mr Nurie & Mr. Vlach for valuable advice.

Regards, Shevade

S. S. Shevade
electroplater - India
2003