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Cyanide destruction in spent strippers

There are a lot of plating shops in SA using the cyanide based Nickel stripper and are having problems destroying the spent solution. Does anyone know of economical ways of destroying this solution. Also we are looking for new ways of destroying cyanide in effluent water.

Julia Hattam
- Johannesburg, South Africa

This response is a little old, but hopefully you'll get it. We also use a cyanide based nickel stripper and I have found no economically safe way to treat it. First, any concentrated CN waste ( i.e., 10,000 ppm or higher) when mixed with chlorine or even liquid hypochlorite will release chlorine gas and other very bad stuff. There is the possibility of dilution, but this is time consuming and in some areas illegal. And then the Nickel CN complex doesn't treat well. We send our waste to Canada to be "pressure cooked". This is even difficult for it requires specialized equipment and releases ammonia ⇦ this on eBay or Amazon [affil links] gas.

Mike Wells
- Jamestown, New York