Need information on acids

[aferland66]

Hello, I'm hoping someone can point me to some information about what to use for different metals when scrapping E Waste.

I have been researching for about a month and I'm not finding a clear answer to my scraping needs. I'm looking to get as many metals out of my E Waste as I can, using the least amount of high cost acids. I don not mind waiting since this is my first try at metal recovery. I am hoping to minimize gases and environmental impact by just taking more time if that's possible. This is a pastime for me, not a business, but I still want to do things the right way.

My plan (if at all possible) is as follows.

1- I've been depopulating boards in an old pan on the stove, and it works very well. After burning 2 boards I found the perfect temp for melting the solder and there is no smell, so I'm hoping no fumes. I still have the fan going just in case.

2- I've cut all the gold fingers off, and removed all the connectors that have pins.

3- Recover what I can as cost effectively as possible with the least amount of fumes.

I've watched Tin/Lead recovery, Copper recovery from boards, Silver recovery and of course Gold recovery. I'm wondering if they could all be done in a specific order? If I could start with Tin/Lead recovery, it would depopulate the boards at the same time, but I don't know if that process would also remove other metals?

I'm hoping there is a way to recover all metals in order from boards like this:

1- Remove Tin/ Lead, depopulating boards at the same time. Precipitate the lead and recover. Recover Tin.
2- Remove Silver and recover
3- Remove gold and recover
4- Shred the boards and recover the left over copper

For IC chips, does the ashing produce toxic fumes or just dust?

One last thing: does anybody know of a chart that shows what acids dissolve what metals at what concentrations? Like Aqua Regia dissolves Gold but what else, AP solution dissolves Copper and what else and so on.

Thank you for your time.

 

[Yggdrasil]

Hello, I'm hoping someone can point me to some information about what to use for different metals when scrapping E Waste.

I have been researching for about a month and I'm not finding a clear answer to my scraping needs. I'm looking to get as many metals out of my E Waste as I can, using the least amount of high cost acids. I don not mind waiting since this is my first try at metal recovery. I am hoping to minimize gases and environmental impact by just taking more time if that's possible. This is a pastime for me, not a business, but I still want to do things the right way.

My plan (if at all possible) is as follows.

1- I've been depopulating boards in an old pan on the stove, and it works very well. After burning 2 boards I found the perfect temp for melting the solder and there is no smell, so I'm hoping no fumes. I still have the fan going just in case.

2- I've cut all the gold fingers off, and removed all the connectors that have pins.

3- Recover what I can as cost effectively as possible with the least amount of fumes.

I've watched Tin/Lead recovery, Copper recovery from boards, Silver recovery and of course Gold recovery. I'm wondering if they could all be done in a specific order? If I could start with Tin/Lead recovery, it would depopulate the boards at the same time, but I don't know if that process would also remove other metals?

I'm hoping there is a way to recover all metals in order from boards like this:

1- Remove Tin/ Lead, depopulating boards at the same time. Precipitate the lead and recover. Recover Tin.
2- Remove Silver and recover
3- Remove gold and recover
4- Shred the boards and recover the left over copper

For IC chips, does the ashing produce toxic fumes or just dust?

One last thing: does anybody know of a chart that shows what acids dissolve what metals at what concentrations? Like Aqua Regia dissolves Gold but what else, AP solution dissolves Copper and what else and so on.

Thank you for your time.

I hope you are not doing this inside in your house!!
Solution chart for acids vs metals can be found on Google.

And ICs and PCBs produce a plethora of really bad and toxic smokes. That us why they need to be pyrolized before incinerating them.

 

[Martijn]

Welcome to the forum.
You have a lot of studying to do.

2- I've cut all the gold fingers off, and removed all the connectors that have pins.

You need to study Hoke's, safety, dealing with waste and the processes that are best suited for the e-waste you have. For fingers the AP process is recommended and also a great first starting material to learn recovery and refining of gold.

I'm looking to get as many metals out of my E Waste as I can, using the least amount of high cost acids.

3- Recover what I can as cost effectively as possible with the least amount of fumes.

If you're talking about basemetals: Not dissolving them would save the most acid and be most cost effective.
Scrapping and separation is the first step. Mechanical, gravitational and magnetic separation or just by handtools.

Cherry pick the parts containing precious metals to recover them for later refining.
Sell the sorted metal.
Plastics are worth money too.

For IC chips, does the ashing produce toxic fumes or just dust?

Tons of info here about proper oxygen free pyrolysing and completely burning the toxic and deadly gases before moving on to safely incinerating the carbonized IC chips material.

One last thing: does anybody know of a chart that shows what acids dissolve what metals at what concentrations

As Yggdrasil pointed out sulubility charts, solubility rules and tables will tell you a lot.
The reactivity series are important to understand to deal with waste or cementing salts from solutions.
Wikipedia is a good reference for physical and chemical properties of an element or compound like mol weight, density or solubility in water.
In the end there is nothing better than experience. So read Hoke's book.

One last thing: does anybody know of a chart that shows what acids dissolve what metals at what concentrations? Like Aqua Regia dissolves Gold but what else, AP solution dissolves Copper and what else and so on.

Here you will find acquaintance tests described you can perform yourself to get a feel for things.

Learn to use the search function and ask if you get lost.
But the most important thing: don't do anything with chemicals before asking us here if it's a good and safe approach.

Most of this chemical stuff will kill you if you disrespect it.
Some seemingly harmless components can contain beryllium, cadmium, nickel, pgm's, chrome or other very toxic metals once in they are in solution.
That white contact paste on heat sinks: do not eat!! And so on.

But none the less, have fun and be safe!

 

[aferland66]

Thank you for that info, I guess I need to do things one at a time.
Since I'm doing this as a pastime and want as much metal as possible, am I correct in thinking depopulating boards and manual sorting is the best first step?

Is hot plate depopulation of boards safe if there is no smoke? There are a lot of videos out there and I see it done by multiple people and it's hard for a beginner to separate good and bad information, that's why I'm here asking. I do keep the heat low and never let the boards smoke or melt. I am taking my time.

 

[Yggdrasil]

Thank you for that info, I guess I need to do things one at a time.
Since I'm doing this as a pastime and want as much metal as possible, am I correct in thinking depopulating boards and manual sorting is the best first step?

Is hot plate depopulation of boards safe if there is no smoke? There are a lot of videos out there and I see it done by multiple people and it's herd for a beginner to separate good and bad information, that's why I'm here asking. I do keep the heat low and never let the boards smoke or melt. I am taking my time.

Not entirely safe no.
It depends on the rest of the conditions.
You did not answer my first question by the way, which will heavily influence the answer.

 

[aferland66]

Not entirely safe no.
It depends on the rest of the conditions.
You did not answer my first question by the way, which will heavily influence the answer.

Yes I was doing it on the stove in an old pan with the fan on. I had not found this forum yet and had only seen videos of people using hot plates so thought it would be ok. I did read enough to know that smoke from the boards is toxic, so did not let the boards smoke (OK I did lightly burn a bit of the first one, but dropped temp and added time)

Thanks for taking the time to answer me

 

[Yggdrasil]

Yes I was doing it on the stove in an old pan with the fan on. I had not found this forum yet and had only seen videos of people using hot plates so thought it would be ok. I did read enough to know that smoke from the boards is toxic, so did not let the boards smoke (OK I did lightly burn a bit of the first one, but dropped temp and added time)

Thanks for taking the time to answer me

DO NOT EVER DO ANY KIND OF REFINING OR RECOVERY IN A HABITED HOUSE OR DWELLING!!!!

When that is said, depopulation is not the worst, but still toxic and dangerous.
Find another place to do it, and if you start using chemicals even more so.
They are corrosive and will destroy all metals in the vicinity.

A different thing, all tools, glassware, pots and pans, once used in the lab they belong ONLY in the lab, period.

 

[Yggdrasil]

Yes I was doing it on the stove in an old pan with the fan on. I had not found this forum yet and had only seen videos of people using hot plates so thought it would be ok. I did read enough to know that smoke from the boards is toxic, so did not let the boards smoke (OK I did lightly burn a bit of the first one, but dropped temp and added time)

Thanks for taking the time to answer me

Aah and welcome to us by the way.
We'll get you in shape I guess

 

[aferland66]

I will start a new thread for the depopulating and sorting since this is outside of my first question.

I'm looking for a chart like this but with more details

 

[aferland66]

DO NOT EVER DO ANY KIND OF REFINING OR RECOVERY IN A HABITED HOUSE OR DWELLING!!!!

When that is said, depopulation is not the worst, but still toxic and dangerous.
Find another place to do it, and if you start using chemicals even more so.
They are corrosive and will destroy all metals in the vicinity.

A different thing, all tools, glassware, pots and pans, once used in the lab they belong ONLY in the lab, period.

Thanks for the warning lol

No I will not be doing anything else in the house, all other parts of the refining will be done is a small shed outside in the spring. I will be building a fume hood, and will have more questions on that since I want to minimize toxic fumes or find a way to neutralize them. At this point I'm learning and sorting/depopulating.

One of my goals here is to be as environmentally friendly as possible, even if it takes me weeks to refine instead of hours.

 

[Yggdrasil]

I will start a new thread for the depopulating and sorting since this is outside of my first question.

I'm looking for a chart like this but with more details

View attachment 60860

You do not need this kind if detail.
For recovery you basically need the Cupric Chloride etch aka AP.
For refining HCl/Bleach or better HCl/ Peroxide will do.
Then SMB or any other Sulfite will drop the dissolved Gold as long as the solution is acidic.

 

[Yggdrasil]

I will start a new thread for the depopulating and sorting since this is outside of my first question.

I'm looking for a chart like this but with more details

View attachment 60860

For any kind of refining of Gold and Silver you need only two acids.
Hydrochloric and Nitric acid.
Nitric is difficult some places so then one do some ad hoc work with either Bleach or strong Peroxide.
For Silver, Nitric is a must and no substitutes can be allowed/used.

This will keep you busy for months/years.

When you are ready to expand, you do not need the charts you are asking for.

 

[aferland66]

For any kind of refining of Gold and Silver you need only two acids.
Hydrochloric and Nitric acid.
Nitric is difficult some places so then one do some ad hoc work with either Bleach or strong Peroxide.
For Silver, Nitric is a must and no substitutes can be allowed/used.

This will keep you busy for months/years.

When you are ready to expand, you do not need the charts you are asking for.

I was asking for the chart since I saw some people recovering even tin/lead from boards.

My thought was, if possible:

1- Remove Tin/ Lead, with it gone the depopulating of the boards is done at the same time. Precipitate the lead and recover. Recover Tin.
I have seen this recovery done on clean boards, now I'm wondering if it can be done on populated boards without sending Gold/Silver/Copper into solution?
2- Remove Silver and recover. Once the above are gone, my hope is to send the Silver only into solutions and precipitate.
3- Remove gold and recover. With the above gone, use AP to remove and recover Copper leaving only gold for Aqua Regia.
4- Shred the boards and recover the left over copper with AP.

What I don't know and was looking for is; will the recovery of the Lead/Tin also send other metals into solution?
Should I AP before Silver recovery?
Is this even possible, or is it a pipe dream

So basically, I'm looking for as complete a recovery as possible, with home tools, no mechanical (except for a rock tumbler I already have and will use to powder the burnt chips)

 

[Yggdrasil]

I was asking for the chart since I saw some people recovering even tin/lead from boards.

My thought was, if possible:

1- Remove Tin/ Lead, with it gone the depopulating of the boards is done at the same time. Precipitate the lead and recover. Recover Tin.
I have seen this recovery done on clean boards, now I'm wondering if it can be done on populated boards without sending Gold/Silver/Copper into solution?
2- Remove Silver and recover. Once the above are gone, my hope is to send the Silver only into solutions and precipitate.
3- Remove gold and recover. With the above gone, use AP to remove and recover Copper leaving only gold for Aqua Regia.
4- Shred the boards and recover the left over copper with AP.

What I don't know and was looking for is; will the recovery of the Lead/Tin also send other metals into solution?
Should I AP before Silver recovery?
Is this even possible, or is it a pipe dream

So basically, I'm looking for as complete a recovery as possible, with home tools, no mechanical (except for a rock tumbler I already have and will use to powder the burnt chips)

As with most chemistry questions.
Yes and No, depending on conditions.
I’m away and using my phone now so it is not the best for replies.

If you want to recover all, forget chemistry and simple.
Definitely forget easy and cheap.
It WILL get complicated and expensive.

 

[aferland66]

As with most chemistry questions.
Yes and No, depending on conditions.
I’m away and using my phone now so it is not the best for replies.

If you want to recover all, forget chemistry and simple.
Definitely forget easy and cheap.
It WILL get complicated and expensive.

Thanks that's what I'm looking for here, straight answers. I'm only starting, not in ant hurry, so I can wait for answers. I posted step one, Depopulating and sorting in the other section. I will start there and keep learning here. When you get back, if you can take the time to let me know any of the steps that are not cost effective, or not possible, that would be great.

I appreciate your time

 

[Golddigger76]

Study with the search bar for the material you want to process.

Just about anything you want or need to know is on the forum.

Start with something small like your gold fingers or gold plated pins to get yourself familiar with the chemistry.

 

[minero74]

Be very careful when using HCL/Bleach
Because it will release Chlorine gas
that is very toxic and If You breath long enough
it will Kill You!
Please Don’t breath those very poisoning fumes/gas.
again this is very serious
It will Kill You if You breath it long enough

When using HCL/Bleach please use a gas mask and a well ventilate it area
away from animals and others persons

If You use HCL/Bleach
And I Hope You Don’t use it.

Just add a drop of Bleach
one at the time when is need it
until gold is dissolve it.

forget the crap thing (1-3) or (1-1)
You can see on internet
That’s a Big mistake from new peoples
that can cost they money and probably their own life.

That measure of (1-1) or (3-1)
that is to much Bleach and will release so much chlorine gas that can kill You and others person and animals

Be very careful when dealing with Chlorine gas

I personally Don’t use HCL/ Bleach never again.

A friend of mine almost died because Chlorine gas.

He had 15 years of knowledge
and He make a little mistake and He almost died

HCL/Peroxide is bit better to use.

 

[minero74]

The biggest mistake that new people do is to treat Precious metals refining as a Hobby

Don’t do that mistake.

Refining is a very serious business,Not a Hobby

(that was a good advise from a person here in the forum).

Before working with acid
learn the trade
Refining can be a very rewarded career.

If You learn it the right,that is how it should be.

Read Hoke’s Book
ask question
Here are lot of good peoples that will gladly answer and will help You in Your endeavor

 

[Martijn]

I will start a new thread for the depopulating and sorting since this is outside of my first question.

I'm looking for a chart like this but with more details

View attachment 60860

You probably mean a list with more metals, not more acids and other solvents.
Like:
https://en.wikipedia.org/wiki/Solubility_tableOr:
https://en.wikipedia.org/wiki/Solubility_chartStick to the acids and processes you have and need, not more.
Now if you look at copper sulfate is soluble, but copper does not dissolve in sulfuric unless its hot and concentrated, so you need experience to understand how metals react to acids when cold, hot, dilute or concentrated, and which metal to treat in which order to avoid problems with separation.

Don't over think it.
Read Hoke's.

 

[Robert Friedrich]

Great article overall you setup is the most important thing ....fumes can be invisible and deadly and saturate things

I've been prepping for about a year I've acquired many different ways to try my timeline is spring till fall wherein can open garage I have a 6 inch vortex fan with carbon filters for direct venting and will run a 20 inch van at door equipment setup within 5 ft of door I also have either masks there are safer ways but not efficient ..... Not matter how long I've been prepping I get new info and thankyou