Sciencemadness Discussion Board

Interesting Method for Stripping Copper Wires

DFliyerz - 27-3-2015 at 19:39

I have a bunch of small copper wires lying around that I would like to get the copper from, but I don't really want to put in the effort of stripping them, and burning them could end up very noxious and dangerous. So instead, I've developed a different way using methyl ethyl ketone (butanone.) To begin, you take some butanone (which can be easily found at your local hardware store,) and take soak your wires in it. They will quickly start to pale and look as though they have expanded, and after about an hour the insulation will have the consistency of wet noodles. You can then just filter off the remaining butanone, and use tweezers to hold on to the inner metal part of the wires, while the insulation will slip right off the wires easily. Personally I just throw away the remaining insulation, but you might be able to recover some of the methyl ethyl ketone by distilling the remains of the insulation.

subsecret - 27-3-2015 at 20:32

Very nice.

Distillation is one thing, but cleaning the residue in the flask is another.

DFliyerz - 27-3-2015 at 21:03

Quote: Originally posted by subsecret  
Very nice.

Distillation is one thing, but cleaning the residue in the flask is another.


Oh yeah, I suppose that's a good point. Also, although it's probably very impractical, wouldn't it be possible to get hydrochloric acid from heating the residue?

AJKOER - 28-3-2015 at 09:18

Personally, inhalation of methyl ethyl ketone fumes is a no no.

Feel better manually stripping the wire, which is good exercise and a lot better for your health in the long run.

DFliyerz - 28-3-2015 at 09:43

Quote: Originally posted by AJKOER  
Personally, inhalation of methyl ethyl ketone fumes is a no no.

Feel better manually stripping the wire, which is good exercise and a lot better for your health in the long run.


Well, part of the problem is that the wires are pretty thin and all less than one foot long, and the bundled wires inside are thin enough to hurt a lot when they poke into your skin.

Etaoin Shrdlu - 28-3-2015 at 10:41

Quote: Originally posted by AJKOER  
Personally, inhalation of methyl ethyl ketone fumes is a no no.

And this is why I believe home chemists should have a least a half-mask respirator, despite the typical viewpoint that they're not necessary. A lot of options open up once the whole "solvent fumes" issue is moot.

aga - 28-3-2015 at 13:09

Hole. Razor blade fixed to poke just far enough into hole.

Push wire through hole.

Lots of Wire? Motorised puller thingy, hopefully rigged up to copper take-up spool and a bin to catch the plastic in.

Sell the copper, pyrolise the PVC to make Oodles of HCl and carbon powder.

blogfast25 - 28-3-2015 at 16:24

Simple mechanical tools for stripping/recycling wires are now available. Don't waste any MEK on this, IMHO.

[Edited on 29-3-2015 by blogfast25]

DFliyerz - 28-3-2015 at 16:36

Quote: Originally posted by aga  
Hole. Razor blade fixed to poke just far enough into hole.

Push wire through hole.

Lots of Wire? Motorised puller thingy, hopefully rigged up to copper take-up spool and a bin to catch the plastic in.

Sell the copper, pyrolise the PVC to make Oodles of HCl and carbon powder.


Hmm, that sounds like it might be a good idea. Any ideas on how an apparatus for pyrolizing the PVC might work?

blogfast25 - 28-3-2015 at 16:46

If MEK swells PVC so well it would be a good solvent for DOP extraction from plasticised PVC. Easy also to distil off the solvent. But that's different subject...

aga - 29-3-2015 at 02:08

Quote: Originally posted by DFliyerz  
Hmm, that sounds like it might be a good idea. Any ideas on how an apparatus for pyrolizing the PVC might work?

Depends on what Scale you want to do it.

The high rate that HCl is released means that you simply need a cotainer with one opening : all air is expelled as soon as HCl production starts.

At the simplest, it can be just an old paint tin with a hole poked in the top, fill with PVC and apply heat.

At about 260C vast quantities of HCl are released, so be prepared to dissolve that in water very quickly indeed (needs a big surface area).

After pyrolysis you'll be left with a chunk of porous carbon in the tin.

Oxydro - 29-3-2015 at 02:30

Don't count on your HCl being all that pure.

http://fire.nist.gov/bfrlpubs/fire87/PDF/f87015.pdf

Check out table 1.

DFliyerz - 29-3-2015 at 07:47

Quote: Originally posted by Oxydro  
Don't count on your HCl being all that pure.

http://fire.nist.gov/bfrlpubs/fire87/PDF/f87015.pdf

Check out table 1.


Well, they're all useful compounds, so as long as I can separate them I won't complain.

mayko - 29-3-2015 at 07:53

#3 is pretty clever in my opinion.

Random - 30-3-2015 at 11:03

Quote: Originally posted by AJKOER  
Personally, inhalation of methyl ethyl ketone fumes is a no no.



Why? I have done this in january also posted the method same as OP's. Solvent can be reaused and wire doesn't need to soak. Just a bottom of the cucumber jar will be enough if you shake and leave it. I have inhaled this acetone while I was getting it off and MEK isn't dangerous either. He isn't going to do it every day, drinking a beer is far worse for your health despite how it counts like nothing.

22,5mL of ethanol ingested is worse than getting few whiffs of MEK imo.

aga - 30-3-2015 at 11:38

Quote: Originally posted by Random  
.. drinking a beer is far worse for your health despite how it counts like nothing.

Quite right.

Beer drinking is best left to the professionals.

engineerman9337 - 3-4-2015 at 09:24

Had similar experience with a popular carcinogenic degreasing agent (Many years ago, before it was banned). Better for your longevity to make a realistic estimation of the value of the monetary return from the little cu wires vs. the value of your lifetime earnings potential.

Random - 5-4-2015 at 10:32

Quote: Originally posted by engineerman9337  
Had similar experience with a popular carcinogenic degreasing agent (Many years ago, before it was banned). Better for your longevity to make a realistic estimation of the value of the monetary return from the little cu wires vs. the value of your lifetime earnings potential.


It depends how much the money is worth to him. Not having enough to eat is as harmful as is inhaling some toxic agent (talking about MEK). But MEK is hardly going to be dangerous anytime, yes girls are using it to strip nail polish, yes it *could* be carcinogen. Your opinion is then really in front of the opinion of average human. You might aswell research how many toxins we eat currently. But do you avoid smoky areas to avoid cancer? It is maybe more dangerous than many not researched carcinogens. Smoke either tobacco or diesel was always carcinogenic.

It's hard to avoid toxins today because not everyone has privilege to do so (think of working class) and replacements for some things will never be available. Much research isn't there either, no money there.