Refining MLCC´s for Palladium and Silver !

[Yggdrasil]

What do you mean directly? Did i have the mlccs in there while I added the sodium hydroxide and then the sugar. So if you are asking if the mlccs were in the beaker will add that stuff then the answer is no.
After I put the mlccs into dilute nitric I then filtered out the mlccs. And many rinses with distilled water. Next I put the beaker back on the hot plate. Without lid, I tried to evaporate much of the liquid. Then i added sodium hydroxide and used my magnetic stirrer until all of the white chloride turned dark to even black. Next I added the sugar, regular sugar ( which I'm your I should used kero syrup and also should have rinsed that sugar before adding the sugar) so after adding that sugar I kept it in hot plate until it all looked dark and uniform color. Did I mess up? I guess I should have rinsed before sugar but all in all I followed instructions instructions according to my research.

That is great, because in your post to which I replied you seemed to just add NaOH to the MLCCs.
Read it again and you will see.

But as Kurt said you need to wash it properly after.
But for 20grams of MLCCs there should just be minute amount of Silver.
Maybe in best case 2 grams, but since these are magnetic I would guess less than one.

 

[Rreyes097]

That is great, because in your post to which I replied you seemed to just add NaOH to the MLCCs.
Read it again and you will see.

But as Kurt said you need to wash it properly after.
But for 20grams of MLCCs there should just be minute amount of Silver.
Maybe in best case 2 grams, but since these are magnetic I would guess less than one.

It looks about a gram in there maybe a little less maybe little more.

 

[Rreyes097]

"So I filtered the 20g mlccs after letting it sit in nitric acid diluted with distilled water for 4 days. After many rinses with distilled water. I then evaporated some so it wasn't so much rinse liquid. I may have lost some values?" This is what I posted. I'm not sure where I confused you but it says right here that I used nitric acid with distilled water.

But either way. My next step is to maybe grind up the 20g of mlccs and put bank into nitric acid and distilled water. To see if I can get any silver left over because since I didn't mill them out grind them I may have left some silver behind. The stannous never showed any positive findings for Pd so I'm going to just double check it. While I do that I'll be looking for information on smelting. And also create a design to build a furnace so I can do more incineration on mlccs and IC chips. And wherever else may be needing. Sound good?

 

[Yggdrasil]

I asked you to give a detailed explanation and this is what you gave us:

We have no means to know what you have been doing in the mean time as this rolls ahead.
When we ask for detailed it needs to be detailed for a reason.

 

[Rreyes097]

I asked you to give a detailed explanation and this is what you gave us:
View attachment 53323
We have no means to know what you have been doing in the mean time as this rolls ahead.
When we ask for detailed it needs to be detailed for a reason.

Of course. I'm not saying anything to cause offense. I just didn't understand where I was unclear in my description of my steps up to this point. So thanks for your help, everytime anyone responds I am truly grateful.

 

[Rreyes097]

By chance would molasses work instead of sugar? Because I don't have Karo but will get it if that's the best option. I'm just wondering.

 

[orvi]

By chance would molasses work instead of sugar? Because I don't have Karo but will get it if that's the best option. I'm just wondering.

If it isn´t hot, reduction is sluggish or even non-proceeding. Regular sugar is more than good for this. Just need to be still very basic and HOT. At least 90°C, and add the sugar in small increments with stirring, as it will quickly heat up and eventually can boil.

With ozt or more batches, I always advise to use the thermometer sticked into the reaction for measuring the temperature. Heat past 95°C preferrably, then began additions of sugar proportional to the silver. It takes just a spoon or two to fully reduce ozt of silver. Temp rise isn´t sudden, it goes slowly and then shoot up quickly. Be prepared.

Never add more if the temperature isn´t higher than 90 °C, because you do not know if there is some unreacted sugar waiting for it´s chance to create boilover. Also, never add more unless you see sharply that temperature raised and then started to DECLINE. Past 113°C, you can experience mild bubbling and past 115°C it isn´t guaranteed it won´t splash the hydroxide all over you

Hot lye in the eye isn´t fun. I experienced it. Despite having face shield

 

[Rreyes097]

The difference in testing style are purely preference.

Use filter paper, or a testing dish, spoon..... All you’re doing is maintaining a controlled space for your sample.

I use a qtip

 

[J.Najam]

Flux for smelting MLCCs - 1/3 borax 1/3 soda ash 1/3 cryolite & "some" fluorspar for thinning

Hi Kurt,

Been researching about MLCCs these past few days and unfortunately I can only procure the aforementioned ; cryolite and fluorspar in bulk quantities (my working would probably be no close to that), I got no other option than that. Also read up on the leach issues mentioned around the forum more than a dozen times. How would you suggest I go with this then? Also is it true most of these magnetic MLCCs contain no PMs at all?

Thanks for your time.

 

[orvi]

Hi Kurt,

Been researching about MLCCs these past few days and unfortunately I can only procure the aforementioned ; cryolite and fluorspar in bulk quantities (my working would probably be no close to that), I got no other option than that. Also read up on the leach issues mentioned around the forum more than a dozen times. How would you suggest I go with this then? Also is it true most of these magnetic MLCCs contain no PMs at all?

Thanks for your time.

Remove as much solder as you can, way you want, pyro or hydrometalurgically. Then smelt. There are multiple possibilities on fluxing, but bear in mind that alumina and barium titanate are not fluxed properly by many common fluxing agents - mainly sodium fluxes. Sodium carbonate or borax won´t help you here.

Best fluxes for classic old titanate MLCCs are silica or boron oxide. I prefer boric acid, since it always liquified the melt properly. For proper liquification, high temperatures must be attained. With silica it is good to be able to go to at least 1350 °C, otherwise it is possible you will spend quite a bit of time with liquification - melts can be a bit viscous at lower temperatures. Induction furnance is the best tool here. Or reliable electric furnance.

Never introduce sodium fluxing agents into the melt, it will make it gooey and metal beads won´t coalesce properly. If you need to flux it, use calcium borate instead (mixed quicklime and boric acid, eutectic mixture).

 

[J.Najam]

There actually are so many ways to skin a cat! it clears up my perspective as well as any complications beforehand however, a request about the following :

1,

Remove as much solder as you can, way you want, pyro or hydrometalurgically.

Crushing to fine powder required for this? Or keep it regular?

2,

silica or boron oxide.

silica sand and dehydrated boric acid?

3,

Induction furnance is the best tool here. Or reliable electric furnance.

Ive read about this in your other posts as well where you've mentioned the benefits of an induction furnace, but well its kind of out of my pocket at the moment. all I can do is build a bit larger furnace and use coke(fuel) with a blower otherwise coal would have to be my best bet.

And electric furnaces here dont go that high. Barely 1000c. And others that do are again quite pricey. So ill weigh my benefits and lean on the side that plays to my advantage

Although Ive a clear picture now of how to go about it, Ill skim them through for the non magnetic ones before heading on.

Will share a listed plan once Im ready to proceed with these.

Thanks for your time

 

[orvi]

There actually are so many ways to skin a cat! it clears up my perspective as well as any complications beforehand however, a request about the following :

1,

Crushing to fine powder required for this? Or keep it regular?

2,

silica sand and dehydrated boric acid?

3,

Ive read about this in your other posts as well where you've mentioned the benefits of an induction furnace, but well its kind of out of my pocket at the moment. all I can do is build a bit larger furnace and use coke(fuel) with a blower otherwise coal would have to be my best bet.

And electric furnaces here dont go that high. Barely 1000c. And others that do are again quite pricey. So ill weigh my benefits and lean on the side that plays to my advantage

Although Ive a clear picture now of how to go about it, Ill skim them through for the non magnetic ones before heading on.

Will share a listed plan once Im ready to proceed with these.

Thanks for your time

It is not true that magnetic MLCCs cannot have palladium. They can. Altough it is less likely than nonmagnetic. Also, it is not guaranteed that nonmagnetic do contain Pd.

Don´t crush anything, it makes removal of solder much harder. And regular SMD MLCCs are small enough that you don´t need to crush them for smelting.

Yes, silica sand or dehydrated boric acid. If you intend to smelt them with boric acid, it is wise to dehydrate it first, and then smelt. As boric acid is dehydrating, it tends to slime and bubble like borax. On smaller scale it does not matter that much, but bigger charges can slime some out, if you fill the crucible too much.

All in all, you don´t need necessarily use induction, but it should go above at least 1250 °C. I can imagine using coke furnance, as it can certainly go past that temperature... But I don´t know what material of crucible you use - as boron oxide is very aggresive flux, and I always used it with graphite crucibles - which cannot be used in open flame furnances due to obvious reasons. Boron oxide nicely flux also magnesia... Maybe alumina is more resistant. Then, silica would be a possibility, but bear in mind that with silica you need to go to higher temperatures than with boric.

Certainly put some pictures if you will smelt with "flame" furnances - we are very curious about the result, since I only smelted these in induction. This could make a good example of what to expect

Good luck.

 

[J.Najam]

It is not true that magnetic MLCCs cannot have palladium. They can. Altough it is less likely than nonmagnetic. Also, it is not guaranteed that nonmagnetic do contain Pd.

With due respect here, I've encountered numerous folks on this forum mentioning to throw away the magnetic ones and aim for the nonmagnetic only, but now that you have laid it out, it'll be worth a try.

Don´t crush anything, it makes removal of solder much harder. And regular SMD MLCCs are small enough that you don´t need to crush them for smelting.

If the outer solder is removed, then would it be feasible to proceed with crushing?

On smaller scale it does not matter that much, but bigger charges can slime some out, if you fill the crucible too much.

Small scale only boss, I don't think it'll ever go to that point. I would've sold these had they been on for good price, but its kind of hard to find the non-trading buyers. They literally buy a throw away price. Will keep the level in mind before proceeding though, halfway should be more than enough for a safe charge?

But I don´t know what material of crucible you use

I aim to purchase the white ceramic silica crucibles for this work, they seem to have a longer life than the grey graphite ones, Specially considering the oxidizing nature of borax that eats the graphite away.

Certainly put some pictures if you will smelt with "flame" furnances - we are very curious about the result, since I only smelted these in induction. This could make a good example of what to expect

I would love to, but I do have a lot to do on my hands, so this could take some time. However, even if it is a mess, it is still coming up here.

Many thanks for your time on this one!

 

[orvi]

I always processed mixed batches, as it was far easier to just dump it all into the crucible and smelt, than separating them into different piles, potentially losing some PM´s.

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You do not need to crush them at all, it is unnecessary - with proper flux like boric acid they will easily dissolve with some stirring in matter of few minutes. Crushing is another unnecessary hassle in my opinion. I can imagine crushing is essential if one is using some ineffective flux mixture (as seen in many youtube videos), but if you will use real flux which will completely dissolve the ceramics, I see no benefit in crushing.

-----

Half of the crucible is OK. You can also put the caps into the crucible, and then start heating and slowly adding boric acid on top. Silica is completely tame during the smelt.

 

[J.Najam]

I always processed mixed batches, as it was far easier to just dump it all into the crucible and smelt, than separating them into different piles, potentially losing some PM´s.

Agreed, makes it a much lesser complicated process with just dumping it all in, BUT - per the bold - we're not risking our health for this?

completely dissolve the ceramics

My question already answered, also boric acid is an easy find and buy

You can also put the caps into the crucible, and then start heating and slowly adding boric acid on top. Silica is completely tame during the smelt.

Sounds great! Can't wait to get started - Although may take some time, BUT from nothing at all it is now going to pure smelting!

 

[Thirmo21]

It is not true that magnetic MLCCs cannot have palladium. They can. Altough it is less likely than nonmagnetic. Also, it is not guaranteed that nonmagnetic do contain Pd.

Don´t crush anything, it makes removal of solder much harder. And regular SMD MLCCs are small enough that you don´t need to crush them for smelting.

Yes, silica sand or dehydrated boric acid. If you intend to smelt them with boric acid, it is wise to dehydrate it first, and then smelt. As boric acid is dehydrating, it tends to slime and bubble like borax. On smaller scale it does not matter that much, but bigger charges can slime some out, if you fill the crucible too much.

All in all, you don´t need necessarily use induction, but it should go above at least 1250 °C. I can imagine using coke furnance, as it can certainly go past that temperature... But I don´t know what material of crucible you use - as boron oxide is very aggresive flux, and I always used it with graphite crucibles - which cannot be used in open flame furnances due to obvious reasons. Boron oxide nicely flux also magnesia... Maybe alumina is more resistant. Then, silica would be a possibility, but bear in mind that with silica you need to go to higher temperatures than with boric.

Certainly put some pictures if you will smelt with "flame" furnances - we are very curious about the result, since I only smelted these in induction. This could make a good example of what to expect

Good luck.

Hello I have a question. Would crushed glass be good substitute for silica sand in such smelting process? I found out from searching its mostly Silica (SiO2): Around 70%, some soda ash and lime. Has anyone tried this?

(And yes i know crushing it to powder is hazardous and that i need ppe).

 

[orvi]

Hello I have a question. Would crushed glass be good substitute for silica sand in such smelting process? I found out from searching its mostly Silica (SiO2): Around 70%, some soda ash and lime. Has anyone tried this?

(And yes i know crushing it to powder is hazardous and that i need ppe).

Definitely not. If you ever seen molten glass, you know why No one want slag that thick. Sodium anything will thicken the slag, mainly if it isn't neutral slag. Sodium slags can be used for basic smelting of low melting things, because melting points are low. However solubility of titanates is low in sodium slags.
Also, at high temperatures sodium oxide start to vaporize and glow is nearly unbearable. Everything is smoked out with white fumes od Na2O... Not plesant. I prefer calcium slags, despite the fact you need to go to higher temperatures.

 

[Thirmo21]

Definitely not. If you ever seen molten glass, you know why No one want slag that thick. Sodium anything will thicken the slag, mainly if it isn't neutral slag. Sodium slags can be used for basic smelting of low melting things, because melting points are low. However solubility of titanates is low in sodium slags.
Also, at high temperatures sodium oxide start to vaporize and glow is nearly unbearable. Everything is smoked out with white fumes od Na2O... Not plesant. I prefer calcium slags, despite the fact you need to go to higher temperatures.

Ok thanks for answer Orvi. Its shame it is unusable as it would be pretty cheap, but oh well now i know

 

[orvi]

Ok thanks for answer Orvi. Its shame it is unusable as it would be pretty cheap, but oh well now i know

Yeah, glass is free... But sand is also very very cheap. You don´t even necessarily need to buy it if you have some sandy deposits nearby... But a 25 kg bag of sand costs around 5 euros here... That will last you for 2 eternities if you are a hobbyist

Silica sand is also good to level up any molds or crucibles if you are smelting. Just pile it onto the surface and level the mold in it. Nothing will catch fire and any spill will be nicely contained. With very high melting point, it is also good for high temperature smelts as some "spacer" between hot crucible and brick surface underneath. It usually starts to sinter around 1400-1500 °C.

 

[Alondro]

Yeah, glass is free... But sand is also very very cheap. You don´t even necessarily need to buy it if you have some sandy deposits nearby... But a 25 kg bag of sand costs around 5 euros here... That will last you for 2 eternities if you are a hobbyist

Silica sand is also good to level up any molds or crucibles if you are smelting. Just pile it onto the surface and level the mold in it. Nothing will catch fire and any spill will be nicely contained. With very high melting point, it is also good for high temperature smelts as some "spacer" between hot crucible and brick surface underneath. It usually starts to sinter around 1400-1500 °C.

I live in the NJ Pine Barrens. It's nothing but sand!

And it's course and rough... and it gets everywhere.... (I hate sand....) ;D