Is there anyone that can offer insight into how to manage a sulfuric acid 
based, potassium oxidizing salts copper etchant waste?

     Hello Everyone,
                    I'm not sure what specifically is included in "Potassium
     oxidizing salts", but this sounds similar to what we call Cobra etch,
     which is a mixture of sulfuric acid and peroxide. I'm guessing that the
     end result is the same in that copper etched ends up as copper sulfate.
     We know that by cooling Cobra etch, the CuSO4 will precipitate, and the
     resulting supernatant can be recycled back into the process.

          If cooling doesn't drop out the dissolved copper, perhaps
     electrowinning could plate it out, but you'll have to evaluate this
     with some EW units, as some don't like a lot of oxidizers in the feed.
     You'll have to pilot this with some mfgrs of these units.

          Also, depending on the cost of the etchant solution, diffusion
     dialysis might be cost effective.

          I've focused my response on ways of recycling the solution as
     opposed to chemically treating it for discharge. Going the treatment
     route, there's different routes depending on whether the copper is
     chelated in this sollution or not.                     Lee Wilmot
                                                            HADCO Corp
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