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Cyanide treatment by hexavalent chromium

I need information about cyanide treatment by hexavalent chromium or another method.

with special thanks

n_pargali
nasir toos industrial complex - mashad , khorasan , Iran

Hello, Mr. Pargali.

I have not heard of treating cyanide by hexavalent chromium and cannot recommend it. Cyanide and hexavalent chromium should be treated separately first to my knowledge.

The cyanide must be kept at a high pH (about 10.5-11.0) while an excess of bleach (sodium hypochlorite) is added to oxidize the cyanide and eliminate it. Acidifying cyanide-bearing waste with hexavalent chromium or any other acid can release deadly HCN gas. Good luck and consider some hands-on training because this can be dangerous. Thanks.

Ted Mooney, P.E.
finishing.com
Brick, New Jersey

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