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Simple help on setting up copper electrolysis

August 8, 2008

My name is Todd and I'm working on a project to purify copper. The copper I have to purify is 95% copper and 5% zinc. Or around that percentage. Can I simply set up a Copper Electrolysis situation that will purify the copper? My question on setting this up is: Can anyone explain in laymen terms how much Copper sulphate, Sulfuric Acid, and Water should I mix together to purify 1 pound of copper/zinc anode to a pure copper cathode? And a secondary question would be how much voltage/amps should I use to do this.

I am not a chemist and do not understand the different nomenclatures of Milliliters, grams, per parts, etc... Please spell it out as simple as possible like 1 gallon water, 1 table spoon copper sulphate, 1 table spoon sulfuric acid....

Thanks in advance to a super novice!

Todd Mueller
hobby - Spanish Fort, Alabama

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This is a personal opinion. If you do not know the difference between terms, your scientific background is too weak to be messing around with strong acid solutions. Also, the copper is normally ground up to a very fine material and dissolved in acid and then the copper plated out with an inert anode.
Do some research with a number of references and not peoples opinions, on "electrowinning"

James Watts
- Navarre, Florida
August 8, 2008

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James,

Thank you for the response, is there any reference material you could direct me to. I've searched all over the net and to be honest no one actually explains it in simple terms.

This can't be that hard. And there are not supposed to be high levels of acid and such. The sulfuric acid can be bought at any autoparts store and the copper sulphate ⇦ this on eBay or Amazon [affil links] can be purchased on eBay for about 10 bucks a pound. I just don't know what mixture to use of each to produce the required effect.

What your talking about is using a leaching process where the acid melts the copper and makes a copper solution and then the solution bonds itself to the cathode when an anode is present, basically using a base metal to convert an electron from the base metal to pure copper and plate itself on the cathode. Same concepts but my copper is already 95 % pure and in a poured anode stick so to speak.

Thanks again for any help anyone can supply.

Todd Mueller
- Spanish Fort, Alabama
August 16, 2008

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August 18, 2008

Hi Todd,
Your proposed procedure may or may not work, depending on what the other 5% is. Your proposal is not the same as extracting copper from ore, but might work.
I would try about 200 grams of copper sulphate penta hydrate per liter of solution. This equals 757 grams per gal which equals 26.5 oz per gal.( or 1 and 2/3 pounds per gal.)
I am not sure of the strength of the battery acid ⇦ this on eBay or Amazon [affil links] , so start out at about 1 quart of acid per gal of solution. Remember, add acid to water and the solution will get HOT!
Your cathode should be about 4 times as big as the anode in area. Only count the face of each. You are looking for about 30 amps per square foot of cathode. Anode to cathode spacing should be about 2 inches and you need agitation of the solution or the cathode for the best efficiency.
You need ventilation as this will entrain a bit of acid in the vapors that come off of the solution.
DISCLAIMER! I assume zero responsibility for anything you do. Be safe!
Jim

James Watts
- Navarre, Florida