Refining MLCC´s for Palladium and Silver !

[Lars100]

Please STOP what you are doing - you are creating MESSES that we are now (likely) going to have to clean up

I say likely clean up because IF (the BIG IF) there was actually Pd in your solution(s) that Pd is now likely tied up in that brown mass - so now we will likely need to clean that up

That brown mass is iron oxide (basically rust) as a result of using steel wool in a nitric solution

Put those filters in a plastic container with a lid on them so they don't dry out (we "may" need to come back to them)

Put the solutions aside until we are able to discuss this in more detail --- in other words - slow down & in fact stop until "others" have chimed in - instead of just jumping in on the advice of one person

I say that because "sometimes" there are mis-understandings in what is posted - which may (or not) lead to mistakes made in the advice given - so it is always good to "wait" & hear what others have to say as someone else may catch the mis-understanding & correct it

I believe that is the situation here

Steel wool does not work well in a nitric solution (which is what you have) & we are now seeing the results of that

Steel wool is better suited with HCl solutions

So Geo did not give bad advice - I "think" he just mis-understood your situation --- waiting for "others" to chime in "may" have avoided the mess(es) you have now created

Trust me - I to sometime mis-understand what I read - post a reply - & then someone else has to correct me

My point being - as someone still learning - slow down & wait for others to chime in so that discussions are more complete - instead of just jumping in on the advice of "one" post

To be continued (all I have time for today)

Kurt

Hi Kurt !
Yes, Sir ! I sit still in the boat and await further instructions.
- I do have some other mass/fluids in jars/bottles which needs to be "rescued" later on. My thinking is that Nitric acid can do wonders with them all (going back to "zero"). But lets try to get something positive out first (and secure the method to use).
Br - Lars

 

[orvi]

During the 1980s and 1990s, Rh was often not even refined out of other PGMs, or gold or silver, it was a cheaper substitute for PT/Pd, it's only large scale commercial use was anti-corrosive plating on silver, especially jewelry.

Depend on where the actual Rh was intended to be used in the mixture. Plating some PGM alloy with Rh in it... I don´t know if it would go as intended. Even in very old appliances (I am used to Soviet manufactured stuff here), all PGMs are refined, palladium contain no Rh when it comes to plating and contact points in relays etc. Only place where I found Rh in old stuff are magnetic contacts, where tip of the pin is Rh plated. And that rhodium is clean, no Pt or Pd, even Ir in it. And we all know that Soviet technology weren´t most efficient and productive. If it was feasible, they would plate mixtures everywhere

From people here on the forum, and also from my experience, I have never heard of other noble metals present in MLCCs (any types, any time period) than Pd, Pt and Ag. So I will be extra cautious.

 

[orvi]

You created some unhealthy portion of iron oxohydroxide. Impossible to filter, or work with in the sane way. Iron sludge always came out when pH rise above 4 (?? - not certain about number, but it is in close proximity, somebody correct me if im wrong). Precipitate of FeO(OH).xH2O dissolve relatively OK in concentrated HCL. But before doing this discuss it here, as you do not make another stepback.

 

[kurtak]

Sorry but no time to post anything today

Will "try" again" tomorrow

Kurt

 

[Lars100]

Sorry but no time to post anything today

Will "try" again" tomorrow

Kurt

Hi Kurt !
No problem. I wont do anything this weekend any way.
- And the test with steel wool is no big issue. I used about 3.5dl for this experiment. We still got 12L to work with
Br Lars

 

[kurtak]

We still got 12L to work with

OK - I am going to "try" to help you out here - BUT - with that said - you have to agree that you are going to slow down & wait for discussion to be complete &/or follow my instructions exactly

In other words - no more just jumping in on the advice of anyone &/or everyone --- that is what got you in trouble with the steel wool thing

To clarify - there are most certainly others here that can help you - BUT - because you are new to this you really need to follow the lead of one experienced refiner - it doesn't need to be me - it can be any - one - of our well respected refiner's on this forum --- or as the old saying(s) go --- too many cooks spoil the broth or too many cooks in the kitchen spoil the pot - meaning that a plan or project fails because there are too many people working on it at the same time

So - if you want my help - do you agree to follow my lead ?

if so - this is going to take some time as we will be doing things (questions & answers) one at a time (to insure I understand your situation) & then move forward with recovery one step at a time

Do you agree ?

Kurt

 

[Lars100]

Hi Kurt !
Yes, thanks. That suits me just fine ! One step at a time !
Remember that I´m not chemist so You will need to have patience with me (and my equipment -which is not a chemistry lab).
Looking forward to hear how You want me to proceed !
Br Lars

 

[kurtak]

Yes, thanks. That suits me just fine ! One step at a time !

OK - Then the first step(s) is going to be me asking some questions so I can "fully" understand your situation

First - you said ----------

We still got 12L to work with

If I understand right - you got to that 12 liters by doing "several" small batches - is that right ?

If so - how many batches ?

Did you keep each batch separate ?

If kept separate - (about) how much solution from each batch ?

In your OP (first post) you said --------

All,
I managed to get together quite a pile of MLCC's which are of 2005 or older... Im far from a chemist but have been working with electronics for many years. Got on the track with Palladium when I learned about all the cathalyst´s being stolen from cars and realized that I had these MLCC´s.
So my goal is to extract as much Palladium and Silver as I can.
Started watching videos on YouTube how to do this refining and brought together necessary acids (so far...). Placed the MLCC´s in pet bottles with about 15% HCL to get rid of the tin (and perhaps outside nickel). Believe I was pretty succesful as I ended up (after about a week) with a purple transparent liquor with grey mass in the bottom (tin ?).
Out with the MLCC's and let them just dry up for a while. Put the purple liquid aside.
Bought two mixers with extra blades and grinded the MLCC's to dust (almost). Then into new pet bottles and added concentrated Nitric acid. Red smoke and red fluid. The mass changed color into greenish/grey.
Let it stand for about a week (shaking every day). Out of the bottles and filtered. I have saved the grey green mass in the filters (dont want to throw away...yet).
The components (whats left of them) into a plastic tray for keeping.
The filtered fluid is black/green and fairly transparent.
Added concentrated HCL and the fluid changed color to dark red and in the bottom a separated beige/red mass appeared (silver ?).

Per the things I highlighted in bold print - that was your "first" batch - is that the "same" process you used on ALL other batches to get to the 12 liters of solution you currently have ?

That includes the step of adding the HCl to "each" batch after the nitic leaching ? --- or did you do that step to only some of the batches ?

In your first post you also said ---------

I have taken some other measures from here but it doesnt seem right.
For ex. adding sodium and formic acid to the dark red fluid...and heat to about 80C. If I filter that potion and heat again it will only become a black mass.
If I pore Nitric Acid in that black mass then it melts into a orange/brown tranparent fluid (which in a way must be right but only takes me backwards...) !

Is that the one & only time you did that ?

Or have you done this with some &/or all the 12 liters we still have ?

To be clear - right now I am only interested in the 12 liters we still have - & if (at this point) it has all gone through the same process - or - if different things have been done with different batches

Right now I don't need details on each batch - just need to know if all the batch have been put through the same process & to the same point - or - if different batches have had different thing done to them

Kurt

 

[Lars100]

Hi Kurt !
Several questions...let me try to address them:
1. We started out ripping the MLCC´s from their paper rolls...some 30kg...took a while The MLCC+s were all from 2005 or older. Some were magnetic and some weren´t. We believed that most magnetic was from the outer electrodes which we were going to wash away. So basically we mixed all the MLCC´s in a big jar.
2. Then we thought that putting about 7-800gram in a 2 liter PET-bottle was a bright idea. We drowned the MLCC´s in 15% HCL for at least a week (two sometimes). In most cases the fluid turned purple after a little while. In a few cases the fluid turned green (and it seemes like the green is dominant over the purple).
We filtered out the fluid and have kept it but Im not sure why...I don´t believe this fluid (purple of green) contain anything else then lead, tin and maybe some nickel.
3. After that we throw together all the MLCC´s in a big jar again and then we took little by little and grinded them in two fruit mixers. I bought some extra blades direct from China (some 30pcs as we destroyed about one blade per kg MLCC).
4. After grinding we put back, again, some 7-800g in new 2 liter pet bottles and addes some 4-5dl Nitric acid.
As You can imagine it was a bit of a dirty story...with boiling, heat and smoke...(we let them boil for themselves...).
The MLCC´s stayed in the soup for just a week and then we filtered them out.
We have kept what remains of the MLCC´s in plastic jars with lids on as I think there are more to get from them. Today I believe that the 4-5dl of concentrated Nitric acid should have been more...buy I don´t know...as for now.
5. We poured the fluids together (again in 2L pet bottles) and then added some 3 dl concentrated HCL to each bottle. The given "recipe" (from point 1) was given to us on You tube. And after about 24 hours we could see "the silver" come together in the bottom of the bottles. Everything going as planned so far !
We separated "the silver" purely by decanting the fluids from eachother. We got "the silver" in a big glass jar (and haven´t really worked with it...we have done some tests of which we can talk later).
6. We continued with "the recipe" and started to add Sodium carbonate in some of the fluid and heating to 80C.
Everything looked fine to begin with but as we started to "boil down" the fluid we just got a black mass (see earlier pictures) while the original on Youtube got a transparent, water clear solution with pd bits floating around in it...just to filter out...
I think we used about two liters trying this method before we stopped.
7. Thats when I Iearned about this Forum...and the Steel wool. For this test we used about 3-4dl of the fluid.
8. Now we got about 12 liter of the basic Nitric/HCL fluid remaining to work with.

- We can forget about the "steel wool mass". It is very little anyway. More interesting with the "sodium carbonate mass". There must be some 2kg of that one and it´s easy to disolve in Nitric acid (turning orange/brown). But we can go for that one later...

Hope the above can be of guidance and I look forward the hear Your thinking about it all !

- If something sounds stupid then it´s probably because my english is poor. Please excuse me for such errors.

Br - Lars

 

[Lars100]

OK - Then the first step(s) is going to be me asking some questions so I can "fully" understand your situation

First - you said ----------


If I understand right - you got to that 12 liters by doing "several" small batches - is that right ?

If so - how many batches ?

Did you keep each batch separate ?

If kept separate - (about) how much solution from each batch ?

In your OP (first post) you said --------

Per the things I highlighted in bold print - that was your "first" batch - is that the "same" process you used on ALL other batches to get to the 12 liters of solution you currently have ?

That includes the step of adding the HCl to "each" batch after the nitic leaching ? --- or did you do that step to only some of the batches ?

In your first post you also said ---------


Is that the one & only time you did that ?

Or have you done this with some &/or all the 12 liters we still have ?

To be clear - right now I am only interested in the 12 liters we still have - & if (at this point) it has all gone through the same process - or - if different things have been done with different batches

Right now I don't need details on each batch - just need to know if all the batch have been put through the same process & to the same point - or - if different batches have had different thing done to them

Kurt

Hi Kurt !
Now I answered You in my own comment block (I should have answered You direct). Anyway my answer is published.
Br - Lars

 

[kurtak]

Hi Lars

Thank you for reply yesterday - this gives me a much better idea of what you have done to get to where you (we) are

I am sending you a PM as I want to discuss some of this in private with you

Kurt

 

[jphayesjr]

Depend on where the actual Rh was intended to be used in the mixture. Plating some PGM alloy with Rh in it... I don´t know if it would go as intended. Even in very old appliances (I am used to Soviet manufactured stuff here), all PGMs are refined, palladium contain no Rh when it comes to plating and contact points in relays etc. Only place where I found Rh in old stuff are magnetic contacts, where tip of the pin is Rh plated. And that rhodium is clean, no Pt or Pd, even Ir in it. And we all know that Soviet technology weren´t most efficient and productive. If it was feasible, they would plate mixtures everywhere

From people here on the forum, and also from my experience, I have never heard of other noble metals present in MLCCs (any types, any time period) than Pd, Pt and Ag. So I will be extra cautious.

Thanks for sharing your experience, Orvi. I accumulated a lot of de-accessioned scrap back in the 70s, 80, 90s from my industrial and govt suction sources. Some, with legitimate help from an uncle who was Chief Metalurgist for GM Electromotive and who was a USAF 2 star, some from friends who worked in Zenith, Motorola, Mallory, Apple, Intel.. One notable exception about items made from Rhodium..."reed relays." In some places, posters call them "quills." Many contain rhodium - silver elements. Some contain silver-palladium/platinum. Some are on PCBs, some are vehicle electrical components, terrestrial, marine, airborne.

 

[MicheleM]

Thanks for sharing your experience, Orvi. I accumulated a lot of de-accessioned scrap back in the 70s, 80, 90s from my industrial and govt suction sources. Some, with legitimate help from an uncle who was Chief Metalurgist for GM Electromotive and who was a USAF 2 star, some from friends who worked in Zenith, Motorola, Mallory, Apple, Intel.. One notable exception about items made from Rhodium..."reed relays." In some places, posters call them "quills." Many contain rhodium - silver elements. Some contain silver-palladium/platinum. Some are on PCBs, some are vehicle electrical components, terrestrial, marine, airborne.

Please, could you post pictures of these items?

 

[jphayesjr]

Please, could you post pictures of these items?

This weekend

 

[Geo]

Thanks for sharing your experience, Orvi. I accumulated a lot of de-accessioned scrap back in the 70s, 80, 90s from my industrial and govt suction sources. Some, with legitimate help from an uncle who was Chief Metalurgist for GM Electromotive and who was a USAF 2 star, some from friends who worked in Zenith, Motorola, Mallory, Apple, Intel.. One notable exception about items made from Rhodium..."reed relays." In some places, posters call them "quills." Many contain rhodium - silver elements. Some contain silver-palladium/platinum. Some are on PCBs, some are vehicle electrical components, terrestrial, marine, airborne.

Be very careful handling reed switches. Not all, but enough of the total amount of them contains liquid mercury. They are called "mercury wetted relay" or equivalent warning on the outer case. They are normally encased in a glass tube that is suspended inside a coil of copper on a plastic spool. Inside the tube are two "reeds" extended towards the other from either end surpassing each other by about a quarter of an inch. They are generally in an "open" position while resting. Each reed will have a mirrored appearance that is liquid mercury that is applied to assure connection of the electrodes. If someone was scrap metal intent, the coils would be cut or just broken off of the board and the glass tube shatters and the reed is cut from the board and collected to sell to someone else. You never know. You have to assume that they are all contaminated and work from there.

 

[MicheleM]

you should look carefully before process them, especially the older ones. An example of modern wetted Hg relays;

https://standexelectronics.com/products/mercury-wetted-reed-relays-general-purpose/
You can find useful info browsing through this link
https://www.pickeringrelay.com/
Another potentially dangerous element is Ruthenium, a PGM inert metal that react strongly to common bleach. It can form Extremely toxic volatile compounds

 

[dpgold]

It’s one of the most important things to know before you proceed.

I use 2 grams of Tin shot in 50ml of Hydrochloric. Filter after dissolving the tin. Works a treat.

how would the solution be affected if the HCL is higher concentration? How would it be different? I used 1 gram if Tin which I scraped away and 5ml of 55percent HCL, should I dilute a bit with water now?

 

[Yggdrasil]

how would the solution be affected if the HCL is higher concentration? How would it be different? I used 1 gram if Tin which I scraped away and 5ml of 55percent HCL, should I dilute a bit with water now?

Where did the quote you commented come from?
Some times the things do not make sense, there is an ongoing discussion regarding getting out PM's from MLCCs.
The OP did not know how to make Stannous that is right, but I do not do the relevance to your quote?
Anyway Stannous is not a very picky chemical.
You put some tin into HCl and let it dissolve as much as it can.
Make sure that there are some extra Tin in there then it will last longer.

 

[dpgold]

Where did the quote you commented come from?
Some times the things do not make sense, there is an ongoing discussion regarding getting out PM's from MLCCs.
The OP did not know how to make Stannous that is right, but I do not do the relevance to your quote?
Anyway Stannous is not a very picky chemical.
You put some tin into HCl and let it dissolve as much as it can.
Make sure that there are some extra Tin in there then it will last longer.

I put 1g of Tin in 5ml of concentratet (55 percent) HCL, part of the Tin was scraped to dissolve faster and I let some bigger pieces to make it last longer, but I was wondering how much more I can dilute it to make a bit more but still usable. What would be the the rule of thumb when to add Tin or more HCL, I used the proportions I have seen on some videos where the ratio was 2 g Tin to 10 ml of 30 percent HCL. Since I used 55 percent it would seem that I could double the amount of Tin and water to my receipe. The quote was from a discussion about MLCC and testing the PGM content.
I have about 4kg of MLCC randomly picked from many different boards over time by me and other people magnetic and non magnetic. I was thinking to put it in 30 percent HCL to keep it wet while I still research how I should go about processing them, any idea?

 

[Yggdrasil]

I put 1g of Tin in 5ml of concentratet (55 percent) HCL, part of the Tin was scraped to dissolve faster and I let some bigger pieces to make it last longer, but I was wondering how much more I can dilute it to make a bit more but still usable. What would be the the rule of thumb when to add Tin or more HCL, I used the proportions I have seen on some videos where the ratio was 2 g Tin to 10 ml of 30 percent HCL. Since I used 55 percent it would seem that I could double the amount of Tin and water to my receipe. The quote was from a discussion about MLCC and testing the PGM content.
I have about 4kg of MLCC randomly picked from many different boards over time by me and other people magnetic and non magnetic. I was thinking to put it in 30 percent HCL to keep it wet while I still research how I should go about processing them, any idea?

You quoted Ohiogoldfever!
And there are no such thing as 55% HCl, concentrated HCl is around 38%.
You only need to dissolve Tin until it can’t dissolve more. Make sure there are some left.

Throw away any magnetic MLCCs. They are nickel, no PMs in them.
Grind the remaining to a fine powder and leach in Nitric.
It will dissolve both Ag and Pd.