> I am hoping you can tell me if there is a way to permanently remove
> the copper by electrolysis and if there is, would you be so kind as
> to describe how to go about it?
Yeah, you could hook up a 5V supply to a couple of electrodes, minding that the positive will corrode so you want to use something corrosion-resistant like sheets of solid graphite (probably not terribly cheap). Copper will plate out on the cathode (negative).
The pool guys probably say you can't because either there's a constant source, or there simply isn't enough to remove it from solution. Even copper metal has some solubility in water, and concievably a lot could dissolve in a whole swimming pool. And that's just pure water; you have all kinds of salts and chlorine and stuff to keep it clean. The chlorine tends to oxidize copper to cupric ions, usually a deep green (concentrated) or light blue (dilute) color
(probably easy to miss against water's normal blue color). Especially if the
pool is acidic, you could hold a lot of copper in solution.
The other problem is the source. First of all, what did it come from? Copper
plumbing? I'd bet it's still there, so to fix it, you need to fix the cause,
too.
So lemme see... you can try to find a stronger, insoluble complex. EDTA (lemme see if I remember that, ethylene diamine tetracetate, yeah think so) is used to complex heavy metals in food and blood, to help prevent spoilage or cure heavy metal poisoning. You should be able to dump in a few ounces or pounds, run the filter and see if that clears it up.
Other ways to remove copper are to raise the pH, precipitating copper hydroxide as a green or blue sludge (if it isn't present as a complex that's soluble in basic pH!), or to add a reducing agent (such as sodium sulfite) that converts it to cuprous ions, or metallic copper. Cuprous ions are less soluble and will precipitate as either white cuprous chloride (which turns green in moist air because it would rather be the oxidized form!) or yellow to orange to brick red cuprous oxide, otherwise known as the mineral cuprite.
Tim
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This seems promising so I fired off another email to Tim
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