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Hi Andu
I’ve gone through a similar process like yours before (and even after) I found this great forum and started to follow the advices given by the pro’s here and their knowledge is so valuable for me, cause when I started to do as they suggested, also the results in my beakers started to show results😃.
I’ve been reading this thread on and on this morning and I have to ask some questions Sir. Hope that’s ok.
In all good intentions, but also for me to learn more :)
And again, I’m just a beginner here.


Been there, done that. But why aluminum? Why not start with copper pieces? Or go straight to cement it out on iron and start over?

What is 2SDP1? Yes, I did google it also😉. A “noicefilter”?


Why did you add peroxide despite kindly advised from pro’s here that peroxide is not needed, it’ll work anyway?

Well, good that you have a “bubbler”. I use an older aquarium air pump with dual hose connectors, so it flow exactly perfect and after i started use it everything goes much faster, sometimes a little bit too fast I did learned a couple of days ago🥹.
/Dennis

(To Moderator: when I inserted the quotes in this reply it didn’t look like it use to. But I’ll see when I’m hitting the “post reply” button😅)
You can simply use the quote function.
The reply funcion seem to be a special quote since it contains a link to the post which is replied to.
 
Why do you want to store AlCl3? Or Al(OH)3 for that matter?

If you don’t actually have a need for it, you can simply drive off the Cl, by roasting, because AlCl3 decomposes to Al(OH)3, @ 100*C, no need for NaOH or other alkali caustic.

In theory calcining the Al(OH)3, will form fairly inert Al2O3
I simply find nice storing reactants, the price is higher than metal itself too.


Hi Andu
I’ve gone through a similar process like yours before (and even after) I found this great forum and started to follow the advices given by the pro’s here and their knowledge is so valuable for me, cause when I started to do as they suggested, also the results in my beakers started to show results😃.
I’ve been reading this thread on and on this morning and I have to ask some questions Sir. Hope that’s ok.
In all good intentions, but also for me to learn more :)
And again, I’m just a beginner here.


Been there, done that. But why aluminum? Why not start with copper pieces? Or go straight to cement it out on iron and start over? I’m I wrong if I guess that you went up with a big amount of “white-ish” sludge?

What is 2SDP1? Yes, I did google it also😉. A “noicefilter”?


Why did you add peroxide despite kindly advised from pro’s here that peroxide is not needed, it’ll work anyway?

Well, good that you have a “bubbler”. I use an older aquarium air pump with dual hose connectors, so it airflowing/stirring perfectly and after i started cementing goes much faster, sometimes a little bit too fast I did learned a couple of days ago🥹.
/Dennis
First of all, these aren't exactly the boards i'm refining, not idea what 2SDP1 (besides a fairly expensive piece by googling, I do not know if it can be removed just by the screws) is, I shared in a different post the two boards i found in each device and the one in the picture is the pcb stuck on a aluminium plate. General PCB processing.

No white sludge, I have what i believe is probably mostly copper, iron and tin oxides cemented on aluminium at the bottom and a nearly clear, darky solution of aluminium, i still get bubbles from the cement, few, i'm yet to separate the liquid then rinse the oxides, i guess i'll filter those after few rinses and store it wet.

It was pretty weak peroxide and I only used 1l in 14l of solution

I am using a aquarium bubbler, I don't know where I left my dual hose pump (aquarium bubbler) but this one even has a regulator, the double hose one didn't :).

I will share few pics of the process later, don't expect quality pictures however.
 
pcb stuck on a aluminium plate
I know exactly what you mean, I have a bunch of similar and there is a lot of goodie’s in them.. firmly stuck on the aluminum plate. Here’s a picture of the kinds I have. I remember they’re also covered with some of the most sticky transparent “stuff” inside, covering the goodie’s that is extremely difficult to get off 😕.
IMG_3716.jpeg

/Dennis
 
Here, I found where I posted both boards, so on the left is the sorts of board i haven't yet processed in any way and share at the beginning of the thread, and on the right is the kind i started attempting to refine This circuit board is way too cool to refine .

Depending on what's inside you could perhaps find something to dissolve it in a easy and affordable way, A plastic to fuel plant to turn the plastic into fuel and gas before proceeding to refine the PCBs or whatever, that would be great, you minimize pollution, make some extra and simplify your procedures.
 
[QUOTE="andu, post: 350418, member: 62684"Depending on what's inside you could perhaps find something to dissolve it in a easy and affordable way, A plastic to fuel plant to turn the plastic into fuel and gas before proceeding to refine the PCBs or whatever, that would be great, you minimize pollution, make some extra and simplify your procedures.
[/QUOTE]
I will open one of those and take a picture.
/Dennis
 
Here, I found where I posted both boards, so on the left is the sorts of board i haven't yet processed in any way and share at the beginning of the thread, and on the right is the kind i started attempting to refine This circuit board is way too cool to refine .

Depending on what's inside you could perhaps find something to dissolve it in a easy and affordable way, A plastic to fuel plant to turn the plastic into fuel and gas before proceeding to refine the PCBs or whatever, that would be great, you minimize pollution, make some extra and simplify your procedures.
Not much of that kind of compounds in there, but general plastics can be pyrolized to fuels if you introduce steam into the process.
I do not imagine it is easy or economical, but the Germans did it during the WW2 out of necessity.
 
Not much of that kind of compounds in there, but general plastics can be pyrolized to fuels if you introduce steam into the process.
I do not imagine it is easy or economical, but the Germans did it during the WW2 out of necessity.
Turning plastic from fuel yields a sorts of oily wax from which you can extract gas, diesel and i think kerosene, at the same time it yields gas, which, with about 50% of it have enough for the whole pyrolisis process, however you only get the wax and the gas unless you have a catalizer. I'm not sure about the steam I think water can generate problems in some cases, perhaps depends of the plastic.
But afaik it's basically like destilation of alcohol, with higher chances of explosion.
 
Turning plastic from fuel yields a sorts of oily wax from which you can extract gas, diesel and i think kerosene, at the same time it yields gas, which, with about 50% of it have enough for the whole pyrolisis process, however you only get the wax and the gas unless you have a catalizer. I'm not sure about the steam I think water can generate problems in some cases, perhaps depends of the plastic.
But afaik it's basically like destilation of alcohol, with higher chances of explosion.
Check up on Pyrolysis and Syngas.
Anyway there is not enough plastic in these components to make that process viable.
Most anything is better than these, even the PCB‘s themselves.
 
Check up on Pyrolysis and Syngas.
Anyway there is not enough plastic in these components to make that process viable.
Most anything is better than these, even the PCB‘s themselves.
There is actually a paper about recovery of tin ( and lead ) from PCB’s, along with the pyrolysis gases, and components.

It basically uses a lead bath, under a layer of molten potassium and lithium salt, to pyrolyses the entire board, leaving the components, a few shards of fiberglass mat, and the copper layers.

The molten mix of potassium and lithium salt, cut off direct access of the molten lead to the air, limiting lead vapor to very low levels. The tin and components are recovered from the lead, which would be tapped from time to time to keep an approximate level amount of lead.

Meanwhile, the pyrolysis gasses can be recovered, or flared off, as needed.
I am currently away from my house and I know I have the paper on my PC at home, but if I can find it on one of my mobile devices, I‘ll try to post it in this thread for use.

I have been giving a lot of thought and consideration for using this method, but I am not super enthusiastic about fishing components from the lead bath.
 

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  • Novel waste printed circuit board recycling process with molten salt (1).pdf
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That was a nice read, I never thought about using lead as collector metal, yes tin.
If no lead was present, why would one have to bother with salts?

Any idea how I turn my (still quite acidic) solution of aluminium from cemented stuff into basically any aluminium compound(chloride seems a good option but would i need to evaporate it up)? Should i neutralize it first? Baking soda made quite a mess last time, used a lot and was basically slow. Found some sodium hydroxide close by.

Could i simply save the solution as it's still acidic for a future use?
 
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That was a nice read, I never thought about using lead as collector metal, yes tin.
If no lead was present, why would one have to bother with salts?

Any idea how I turn my (still quite acidic) solution of aluminium from cemented stuff into basically any aluminium compound(chloride seems a good option but would i need to evaporate it up)? Should i neutralize it first? Baking soda made quite a mess last time, used a lot and was basically slow. Found some sodium hydroxide close by.

Could i simply save the solution as it's still acidic for a future use?
Why don't you follow the ordinary waste disposal program?
That will cost some time and energy, what you now are doing will probably be more expensive then buying the materials through ordinary channels.
After Aluminum, nothing accessible is left for cementing, within reasonable cost, just do the ordinary pH adjustments, drop the Hydroxides and filter,
before disposing the liquids, preferably through evaporation.
 
There is actually a paper about recovery of tin ( and lead ) from PCB’s, along with the pyrolysis gases, and components.

It basically uses a lead bath, under a layer of molten potassium and lithium salt, to pyrolyses the entire board, leaving the components, a few shards of fiberglass mat, and the copper layers.

The molten mix of potassium and lithium salt, cut off direct access of the molten lead to the air, limiting lead vapor to very low levels. The tin and components are recovered from the lead, which would be tapped from time to time to keep an approximate level amount of lead.

Meanwhile, the pyrolysis gasses can be recovered, or flared off, as needed.
I am currently away from my house and I know I have the paper on my PC at home, but if I can find it on one of my mobile devices, I‘ll try to post it in this thread for use.

I have been giving a lot of thought and consideration for using this method, but I am not super enthusiastic about fishing components from the lead bath.
I found this a few years back too.
The clue here seem to find a salt combination that is heavy enough for the glass fibers to float on top.
And with a reasonable melting point.
Then just skim off the glass mass and empty the Metal bath from time to time.
So easy and so hard......
 
So easy and so hard......
Agreed LOL

That said, it doesn’t stop me from trying to find processes that fit or come close to fitting my intended result/situation…the learning is at least half the fun, and trying to find non-paywalled papers, is 90% of the research battle.
 
Agreed LOL

That said, it doesn’t stop me from trying to find processes that fit or come close to fitting my intended result/situation…the learning is at least half the fun, and trying to find non-paywalled papers, is 90% of the research battle.
Paywall cheatcode : Sci-Hub: breaking academic paywalls since 2011
For most publications with a DOI number.

Göran
 
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