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General => General Technical Chat => Topic started by: Ig_sherwood on December 19, 2016, 11:11:58 pm

Title: Gold scrapping from plastic plugs ecc...
Post by: Ig_sherwood on December 19, 2016, 11:11:58 pm
Hi there ,so basically i have this jar with pure acetone and pieces of plastics which containing gold plated contacts .
My main problem is that i not yet able to melt all these plastic.
It seems like the pure acetone can't done this job on every type of plastic inside my jar .
At this point did you know some solution to make this job done ?
How i can melt all types of plastic inside my jar ?

Thanks .
Title: Re: Gold scrapping from plastic plugs ecc...
Post by: ataradov on December 19, 2016, 11:32:30 pm
What do you plan to do with the metal afterwards? This jar will contain less than 1 gram of the actual gold metal.

It will probably be easier to burn the plastic stuff. And then use acids to dissolve regular metals and smelt the remainder to extract gold.

PS: It is not worth the time to do this, unless you have tons of this scrap.

Here is "instructional" video:
https://www.youtube.com/watch?v=HhuwO8AjM7k (https://www.youtube.com/watch?v=HhuwO8AjM7k)
Title: Re: Gold scrapping from plastic plugs ecc...
Post by: Ig_sherwood on December 19, 2016, 11:39:30 pm
I have a lot of this stuff and im scared to burn the plastic ,because i think that this will make me loose a lot of plated gold ....
Title: Re: Gold scrapping from plastic plugs ecc...
Post by: ataradov on December 19, 2016, 11:41:05 pm
Why would you loose it? Gold does not oxidize, so it will remain in the ash. Chemicals and processes involved in extracting it from ash are way more scary.

And as video shows, burning is not really necessary. You can just grind this stuff to expose more surface area, and the use chemicals to extract gold.
Title: Re: Gold scrapping from plastic plugs ecc...
Post by: Ig_sherwood on December 19, 2016, 11:44:14 pm
(http://i.imgur.com/Sn81vKr.jpg)
(http://i.imgur.com/afKUCpq.jpg)
Title: Re: Gold scrapping from plastic plugs ecc...
Post by: Ig_sherwood on December 19, 2016, 11:50:34 pm
Im not willing to threat my stuff with chemicals to extract the final gold.
I'm not good with chemistry and for me is pretty risky to play with heavy chemicals as my health has problems.
The thing i wanna realize is to sold all this scraps without plastic and stuff to make the shipment less expensive.
Title: Re: Gold scrapping from plastic plugs ecc...
Post by: ataradov on December 19, 2016, 11:53:06 pm
Then burning is the best way to go. You will not find a common household chemical that will cleanly dissolve all plastics used in electronics.

You just need to check with that recycling facility will accept electronics in this form.
Title: Re: Gold scrapping from plastic plugs ecc...
Post by: ataradov on December 19, 2016, 11:54:24 pm
But it is still not worth it. Even if you extract all metals from there, the cost of gold will not cover the shipping.
Title: Re: Gold scrapping from plastic plugs ecc...
Post by: Ig_sherwood on December 19, 2016, 11:59:29 pm
But it is still not worth it. Even if you extract all metals from there, the cost of gold will not cover the shipping.

Very sad  :'(
But however ,it's also my own curiosity to learn about chemicals which can dissolve completely the plastic.
In any case i will follow your advice ,but before and maybe i will try to heat-up the acetone ,maybe this would accelerate the reaction with the plastic . 
Title: Re: Gold scrapping from plastic plugs ecc...
Post by: ataradov on December 20, 2016, 12:04:05 am
The problem is that you will need a lot of acetone. At some point acetone or any other solvent will be saturated with everything it could dissolve.

You can't turn this mass of plastic into a liquid all at once. You will end up with a paste-like substance at best. And then you will have to extract metals from there.
Title: Re: Gold scrapping from plastic plugs ecc...
Post by: jpanhalt on December 20, 2016, 12:32:38 am
Actually gold does oxidize in a chemical sense.   It has a valences of +1 and +3 according to that nomenclature.  It does not form an oxide per se under normal atmospheric conditions.

An easier way to recover the gold might be to dissolve it in nitric acid (with NaCl or HCl present). And then recover it from that solution.  I suspect on the hobbyist level that the nitric acid and subsequent recovery will cost more than the gold recovered.

John
Title: Re: Gold scrapping from plastic plugs ecc...
Post by: helius on December 20, 2016, 12:33:05 am
While true that gold can't burn, you could in theory lose some via "fly ash" depending on setup. Separating gold from the metal scrap will require prussic acid and is really not for the inexperienced.
Title: Re: Gold scrapping from plastic plugs ecc...
Post by: ataradov on December 20, 2016, 12:35:04 am
Actually gold does oxidize in a chemical sense.   It has a valences of +1 and +3 according to that nomenclature.  It does not form an oxide per se under normal atmospheric conditions.
Well, yes, even oxygen oxidizes under the right conditions. That's a technicality.

An easier way to recover the gold might be to dissolve it in nitric acid (with NaCl or HCl present).
You don't want to do this unless you have a proper fume hood. Probably don't what to have this stuff at home anyway :)
Title: Re: Gold scrapping from plastic plugs ecc...
Post by: jpanhalt on December 20, 2016, 12:39:28 am
Quote
Well, yes, even oxygen oxidizes under the right conditions. That's a technicality.

Hardly a technicality.   Gold chloride is a useful reagent.

An easier way to recover the gold might be to dissolve it in nitric acid (with NaCl or HCl present).
Quote
You don't want to do this unless you have a proper fume hood. Probably don't what to have this stuff at home anyway :)

Why not do it in the same place you plan to burn the mixture of undefined plastics?  I woud be far more worried about the products from that combustion than I would be from a little nitric acid.  Let's just agree that neither should be done in a closet.

John