Summary for ferric chloride use in waste treatment Discussion
Ferric chloride use in waste treatment is the core question here: Karl Weyermann asked whether adding ferric chloride as a settling agent in a wastewater process for zinc, nickel, copper, chrome, and cyanide could interfere with final cyanide testing. The answer says ferric chloride is really more of a coagulant, and whether it is the best choice depends on the specific waste stream. The responder also notes personal experience that ferrous sulfate worked better. On the testing question, the key point is that FeCl3 should have no effect on cyanide analysis if the analysis is being done properly. So the thread suggests the chemical choice matters for treatment performance, but ferric chloride itself should not distort a correctly performed cyanide test.
Q. I began to use ferric chloride
⇦ on
eBay or
Amazon [affil link] in my waste water treatment process where I treat for zinc, nickel, copper, chrome, and cyanide. The ferric chloride
⇦ on
eBay or
Amazon [affil link] is used as settling agent. I been told that the ferric chloride
⇦ on
eBay or
Amazon [affil link] will interfere when testing for cyanide levels in the final discharge stream. Could this be true?
Karl Weyermann
– Winston-Salem, North Carolina
December 15, 2011
It’s really more of a coagulant. Whether it’s the best thing to use depends on your waste. I always had better luck with ferrous sulfate
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FeCl3 addition will have no effect on the cyanide analysis, if it is being done properly.
Dave Wichern
Consultant – The Bronx, New York
December 16, 2011
Ferric should work but I prefer ferrous sulfate
⇦ on
eBay or
Amazon [affil link] and it has been used for years for cyanide destruction, but as mentioned earlier it depends on your water. I know that iron can give false chrome readings in some testing but I have never heard of this with cyanide. If this is a stream that has elevated chrome I would not rule it out.
Brian Wodetzki
– Valparaiso, Indiana, USA
December 24, 2011