Sciencemadness Discussion Board

Reduction of copper wire to powdered copper via H2SO4

kt5000 - 11-3-2014 at 16:37

I was thinking of trying this, and wondering if it will work. I have a ton (more like 15 lbs) of scrap copper wire. Rather than cutting it all into tiny bits, would the following work?

1) Mix copper wire with H2SO4 to produce copper (ii) sulfate:

Cu + H2SO4 ==> CuSO4 + H2

2) Add scrap aluminum (more reactive) to precipitate out solid copper powder:

Al + 3CuSO4 ==> Al2(SO4)3 + 3Cu

Seems like it would work.

DraconicAcid - 11-3-2014 at 16:48

Your first reaction will not work. Copper does not react readily with sulphuric acid. If you have concentrated hydrochloric acid, then

2 Cu + 4 HCl + O2 -> 2 CuCl2 + 2 H2O works, although slowly.

Copper(II) chloride will work better with aluminum than copper(II) sulphate.

bismuthate - 11-3-2014 at 16:56

H2SO4 will react with copper but not under normal conditions
http://www.youtube.com/watch?v=arlYPz3EP7A
Although Draconic acid is right CuCl2 is much, much faster. If you do make copper chloride you should add H2O2 to the HCl.

Metacelsus - 11-3-2014 at 17:00

You could just buy copper sulfate (at most hardware stores, the pentahydrate is sold as root killer).

blogfast25 - 12-3-2014 at 05:49

Quote: Originally posted by kt5000  
I was thinking of trying this, and wondering if it will work. I have a ton (more like 15 lbs) of scrap copper wire. Rather than cutting it all into tiny bits, would the following work?



Wow. The processing cost you're adding would make your copper uncompetitive, if selling it as scrap is your purpose.

DrChemistRabbit - 12-3-2014 at 06:23

the first reaction doen't work.you can dissolve copper in nitric acid,then add NaOH to produce CuO,dissolve in sulfuric acid,and react with hydrazine.and you can also get pure copper from the electrolysis of copper chlorine solution.
aluminum is not a good reducer,because aluminum is always oxidized,and the aluminum oxide is impurities,that's annoying

[Edited on 2014-3-12 by DrChemistRabbit]

[Edited on 2014-3-12 by DrChemistRabbit]

blogfast25 - 12-3-2014 at 09:53

Quote: Originally posted by DrChemistRabbit  
the first reaction doen't work.you can dissolve copper in nitric acid,then add NaOH to produce CuO,dissolve in sulfuric acid,and react with hydrazine.and you can also get pure copper from the electrolysis of copper chlorine solution.
aluminum is not a good reducer,because aluminum is always oxidized,and the aluminum oxide is impurities,that's annoying

[Edited on 2014-3-12 by DrChemistRabbit]

[Edited on 2014-3-12 by DrChemistRabbit]


And all this for a bit of scrap copper??? Com'on...

TheChemiKid - 12-3-2014 at 13:25

And Hydrazine, not many people have that lying around.

Metacelsus - 12-3-2014 at 14:02

Copper wire is generally pure, as impurities hurt the electrical properties. However, if you really want to refine it you could use electrorefining:

https://en.wikipedia.org/wiki/Copper_extraction_techniques#E...

WGTR - 12-3-2014 at 14:30

Bear with me, I'm copying this from a scrap of paper that is a few years old.

10g CuSO4.5H2O in 63mL solution is preheated to 70°C. 3g of Ascorbic Acid (C6H8O6) in 125mL of solution is preheated to 70°C.
The CuSO4 solution is added drop-wise to the stirred C6H8O6 solution over a period of 60 minutes. At the same time that
the CuSO4 is being added, ammonia solution is also being added drop-wise, such that the pH never deviates from the 6-7
range. I was able to achieve copper powder from this; not as fine as that reduced by hydrazine, but still fine nonetheless.

http://www.sciencedirect.com/science/article/pii/S0167577X06...

http://www.sciencemadness.org/talk/viewthread.php?tid=2654


[Edited on 3-12-2014 by WGTR]

Mailinmypocket - 12-3-2014 at 16:40

You may need to translate this but it's basically the same as the above mentioned method

http://lambdasyn.org/synfiles/kupferpulver.htm