Processing MLCC's

Hello everyone, I'm going to start a new topic for the sake of processing MLCC's. I've been toying around Since summer with MLCC's and tried a lot of different methods, manly acid based leaching. And with many different acid combinations. Since everyone has a different process and or method in dealing with MLCC's, It would be nice to compile a process from all the members that have Successfully processed them. By "Successfully" I mean The process is done in a reasonable time frame and has good yields. Because many Methods do work but take very long (an month for an instance) or are not very successful in recovering good yields. One has to make a distinction between Nickel based electrodes en Palladium based electrodes. And almost all MLCC's contain Silver combined with other metals as an outer terminal plating. Nickel based electrodes can be easily be separated from the Palladium based ones. Namely with a "rare earth magnet" or a neodymium one, which is simple acquired from a Computer Hard-drive.

Typical yields; (updated) - Caution! These are only yields for MLCC's that do Contain Pd -
Pd 1 - 3%
Ag 3 - 13%
Pt 0.3 - 0.6% (Not all contain Pt, but sometimes they do)


SMD resistors Have a similar yield results as the ones I presented above.
You also have SMD array's which have sometimes more yields, because they have more layers.
However take notice that not All MLCC's contain Pd Sometimes they only contain Ni & Ag
If you have mixed MLCC's the yield may vary for the Pd (one half has 2% yield and other half has 0% yield which results in a total 1%)
So when we speak about "Pd 1.5 - 3%" this is only an average yield number for the MLCC's that DO contain Pd.
When you acquire MLCC's try to get them as per kind and not mixed. So when you assay them per type u have a stable yield.

Let me also enlighten everyone that their are a lot of different types and sometimes with completely different yields, this is said to try prevent unnecessary posts on this topic.

The new method I want to present, Which is still untested and a hypothesis based on some sound thinking. But it still might not work depending on how the material will co-operate.

This method is a physical extraction of the PM's in the MLCC's, mainly for the clean Palladium based ones. ("clean" here refers to the outer terminals not containing any solder, like lead and tin.)

The MLLC's are ground or crushed to a fine powder. Then melted with appropriate fluxes (mainly borax) and poured into a conical mold, so that the metal is easily separated from the slag.
Around 13% of MLCC's is composed of metal, the rest would be Zirconium dioxide (87%) or an other ceramic with similar properties. Their might also contain other materials, depending on the manufacturer, like bonding material. A suitable crucible for this process would be made out of Alumina. The stirring rod must be also a Quartz stirring rod. No graphite materials are used in this process because of the catalytic properties of Palladium, which does tends to complicate things. The conical mold would be composed out of steel. One could either use an induction based furnace or an propane furnace. The molten matter will have to be stirred good when a propane furnace is used. They will have to reach around 1250°C, Because the Silver and Palladium will form an alloy that melts around 1200°C With an average percentage of 81% silver and 19% Palladium by weight.

If this process would be successful, then the next step would be to separate the Palladium from the silver or vise versa with known methods.

This is as far I have gotten with the thought process, Feel free to chime in and discuss this method or present other plausible means.

I hope it's readable, English is not my native language. If it's not then forgive me for the deficiency of my English language.

9kuuby9 said:

SMD resistors Have a similar yield results as the ones I presented above.

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Can you (or anyone) substantiate that claim?

I've gone out of my way to only remove MLCCs rather than all the SMDs on the boards I've stripped down. If the SM resistors have similar yields, WOW have I wasted some time with that.

chlaurite said:

9kuuby9 said:

SMD resistors Have a similar yield results as the ones I presented above.

Click to expand...

Can you (or anyone) substantiate that claim?

I've gone out of my way to only remove MLCCs rather than all the SMDs on the boards I've stripped down. If the SM resistors have similar yields, WOW have I wasted some time with that.

Click to expand...

http://www.venkel.com/docs/part-pdfs/resistors-mini-catalog-venkel.pdf

Page 6,-General Purpose Resistors- under "Termination" you have 2 sorts, Namely Tin over Nickel and Silver over Palladium.

Let me make it clear that they have similar yields to MLCC's but still have a general lower yield. Because MLLC's have a capacitance, therefore Electrodes. So the outer termination and Electrodes contain PM's. While Resistors only have the outer termination that contains PM's. Having at it's core a substance that offers resistance and so PM's are not fit for that role, because PM's have a good conductivity with a very small amount of resistance. Which will not act as a resistor given it's primary role.

9kuuby9 said:

Let me also enlighten everyone that their are a lot of different types and sometimes with completely different yields, this is said to try prevent unnecessary posts on this topic.

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To put it simply, Any or All the PM value of resistors are contained in the metal end caps along with the solder if parts are used and recovered.
So basically any resistors manufactured before ROHS compliance will be junk as the metals will be tin/lead composition compatible.

To be honest it isn't really worth discussing the "possible" materials it contains. As I said many times

RoHS is often referred to (inaccurately) as the 'lead-free directive', but it restricts the use of the following six substances:
Lead (Pb)
Mercury (Hg)
Cadmium (Cd)
Hexavalent chromium (Cr6+)
Polybrominated biphenyls (PBB)
Polybrominated diphenyl ether (PBDE)

In Europe this started on 2003 and the rest of the world around 2006.

Now Tin (Sn) is not restricted, Thus it is still used a lot alongside with Nickel in the outer termination plating.

So the only difference is Lead here, Since it's only restricted it is still used.

Any mid-grade to high grade components are used in quality products. For instance a Computer Motherboard. Low-grade components (mostly nickel and tin) are used in poor quality products or those that do not need very good quality components, such as a computer power supply. (The main subject -components here are SMT's or SMD's)

To determine the grade of the component is to look at what the particular scrap is used for and what it's purpose is in circuitry.

And again;

9kuuby9 said:

Let me also enlighten everyone that their are a lot of different types and sometimes with completely different yields, this is said to try prevent unnecessary posts on this topic.

Click to expand...

9kuuby9 said:

To be honest it isn't really worth discussing the "possible" materials it contains. As I said many times

RoHS is often referred to (inaccurately) as the 'lead-free directive', but it restricts the use of the following six substances:
Lead (Pb)
Mercury (Hg)
Cadmium (Cd)
Hexavalent chromium (Cr6+)
Polybrominated biphenyls (PBB)
Polybrominated diphenyl ether (PBDE)

In Europe this started on 2003 and the rest of the world around 2006.

Now Tin (Sn) is not restricted, Thus it is still used a lot alongside with Nickel in the outer termination plating.

So the only difference is Lead here, Since it's only restricted it is still used.

Any mid-grade to high grade components are used in quality products. For instance a Computer Motherboard. Low-grade components (mostly nickel and tin) are used in poor quality products or those that do not need very good quality components, such as a computer power supply. (The main subject -components here are SMT's or SMD's)

To determine the grade of the component is to look at what the particular scrap is used for and what it's purpose is in circuitry.

And again;

9kuuby9 said:

Let me also enlighten everyone that their are a lot of different types and sometimes with completely different yields, this is said to try prevent unnecessary posts on this topic.

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You seem to be quite wrong with this statement.
Tin/lead was the common solder joint used before ROHS and ""ALL Resistors"" used in consumer electronics were worthless as far as PM's were concerned before ROHS removed the lead and replaced it with silver and copper.

Exceptions were on some military and medical electronics that required a solder other than tin/lead prior to 2006

PS. I'm not the one that included "resistors" in your thread, which brought on my correction of misstated information.

Some evidence supporting your claim would be nice. :mrgreen:

9kuuby9 said:

Some evidence supporting your claim would be nice. :mrgreen:

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I do believe YOU were asked the for same information above :shock:

YOU are also the one stating a device made of basically carbon and ceramics (ie. resistors) are made with PM's other than what is contained in the solder joint.
I come from the electronics manufacturing industry and have YET to see a "common resistor", whether thru hole or SMD, made with PM's. I left the industry at the same time ROHS became law here in the US but keep active in the industry knowledge.

Here is a link to wiki that describes most resistors available publicly;
http://en.wikipedia.org/wiki/Resistor

Because the time during which the sputtering is performed can be controlled, the thickness of the thin film can be accurately controlled. The type of material is also usually different consisting of one or more ceramic (cermet) conductors such as tantalum nitride (TaN), ruthenium oxide (RuO2), lead oxide (PbO), bismuth ruthenate (Bi2Ru2O7), nickel chromium (NiCr), or bismuth iridate (Bi2Ir2O7).

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They are called SMT resistors.

I'm not talking about internal electrodes or in this case the "thin film".

"You cannot teach a man anything. You can only help him find it for himself." Galileo Galilei (1564-1642) We really have to apply this now in your case. 8)

Re read what I wrote. And a hint, termination...

again;

9kuuby9 said:

Let me also enlighten everyone that their are a lot of different types and sometimes with completely different yields, this is said to try prevent unnecessary posts on this topic.

Click to expand...

I will not go into further discussion about SMT resistors yields.

9kuuby9 said:

They are called SMT resistors.

I'm not talking about internal electrodes or in this case the "thin film".

"You cannot teach a man anything. You can only help him find it for himself." Galileo Galilei (1564-1642) We really have to apply this now in your case. 8)

Re read what I wrote. And a hint, termination...

again;

9kuuby9 said:

Let me also enlighten everyone that their are a lot of different types and sometimes with completely different yields, this is said to try prevent unnecessary posts on this topic.

Click to expand...

I will not go into further discussion about SMT resistors yields.

Click to expand...

The link I posted above was about ALL types of resistors not just Surface Mounted Devices.
SMT = Surface Mounted Technology.

from above;

electrodes can be easily be separated from the Palladium based ones. Namely with a "rare earth magnet" or a neodymium one, which is simple acquired from a Computer Hard-drive.

Typical yields;
Pd 1.5 - 3%
Ag 7 - 13%
Pt 0.3 - 0.6% (Not all contain Pt, but sometimes they do)


SMD resistors Have a similar yield results as the ones I presented above.

Click to expand...

If you feel the need to resort to childish games by referring to my quote or any other stupid Bull... instead of accepting a correction on a mistaken representation you made, Then enjoy looking like the fool alone, as I have no desire to stoop to your level on this forum.

I have no more to say on this matter.

Don't take it too personal, let's put some sand over it. :mrgreen:

this has the potential to be a very productive thread. please do not destroy it before it starts by nit-picking. resistors are normally black with numbers and are the same shape as a MLCC. this has been discussed before and yields were reported but i dont think the threads went very far. some good solid numbers would be fantastic as most people who deal with electronics may or may not find this information useful. please continue 9kuuby9.

Geo said:

this has the potential to be a very productive thread. please do not destroy it before it starts by nit-picking. resistors are normally black with numbers and are the same shape as a MLCC. this has been discussed before and yields were reported but i dont think the threads went very far. some good solid numbers would be fantastic as most people who deal with electronics may or may not find this information useful. please continue 9kuuby9.

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I would like to read more about the ruthenium in resistors. Do they contain an amount of Ru that could make the processing of resistors for Ag and evt. Pd dangerous? Is there a save way to form Ru compounds under the process, so it could be given to a professional in a more stable form like (NH₄)₂[RuCl6] or Ru(IV)0₂?

Geo said:

this has the potential to be a very productive thread. please do not destroy it before it starts by nit-picking. resistors are normally black with numbers and are the same shape as a MLCC. this has been discussed before and yields were reported but i dont think the threads went very far. some good solid numbers would be fantastic as most people who deal with electronics may or may not find this information useful. please continue 9kuuby9.

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Don't worry Geo, I've benefited a lot from this forum, from all our respectable users. So some contribution in return would be the least thing I could do. :mrgreen:

Here is a broader perspective on the structure of a SMT resistor.

solar_plasma said:

I would like to read more about the ruthenium in resistors. Do they contain an amount of Ru that could make the processing of resistors for Ag and evt. Pd dangerous? Is there a save way to form Ru compounds under the process, so it could be given to a professional in a more stable form like (NH₄)₂[RuCl6] or Ru(IV)0₂?

Click to expand...

With Hydrolysis you can make (NH₄)₂[RuCl₅(OH)] from (NH₄)₂[RuCl6]. Since it's in it's Oxide form (RuO) it's easier to form the Ammonium complex salt before the Hydrolysis.

And also never introduce Potassium chlorate when Ru is present, Otherwise you'll be creating fireworks.

Reduction of the salt to elemental metal happens in a 800°C heated hydrogen environment.

Here is a more updated process of the above presented one;

The MLLC's are ground or crushed to a fine powder. Then melted with appropriate fluxes (mainly borax and Cryolite ). Cryolite Decreases the melting temperature of Mineral oxide ceramics and makes it liquefied, So the mixture becomes more easier to stir and for silver to do its job as a collector. It’s then poured into a conical mold, so that the metal is easily separated from the slag.
Around 13% of MLCC's is composed of metal, the rest would be Zirconium dioxide (87%) or another mineral ceramic with similar properties. It might also contain other materials, depending on the manufacturer, like bonding material. A suitable crucible for this process would be made out of Clay Graphite, This is due to the harshness of the Cryolite Flux on Crucibles. The stirring rod could be also a Quartz stirring rod or a borax coated Graphite one. Heat up the graphite rod and give it a borax coating, it will have to be renewed with every use of course. Borax will minimize the interaction of Palladium with Graphite. When using Cryolite, I would advice to use a graphite rod. Since Quartz is also an oxide mineral and might end up molten in the Crucible. The conical mold would be composed out of steel. One could either use an induction based furnace or an propane furnace. The molten matter will have to be stirred good when a propane furnace is used. They will have to reach around 1250°C, Because the Silver and Palladium will form an alloy that melts around 1200°C With an average percentage of 81% silver and 19% Palladium by weight. Silver here acts as a collector and a means of lowering the melting temperature. Depending on the silver content, One could add more silver to make the melt a more feasible process.

Fluorspar or Calcium fluoride Could also be added to the flux mixture to ease the process of melting.

Where/how did you get these numbers? what was being processed exactly?

Metal yield from smelting sounds kinda low...

samuel-a said:

Where/how did you get these numbers? what was being processed exactly?

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By extensive chemical leeching of MLCC's

samuel-a said:

Metal yield from smelting sounds kinda low...

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What are you referring to Sam?

9kuuby9 said:

What are you referring to Sam?

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Have you actually smelted MLCC's scrap or are you projecting the numbers you've got from chemical leaching over a theoretical smelting process?
Something is missing. What have you processed exactly?

samuel-a said:

Have you actually smelted MLCC's scrap or are you projecting the numbers you've got from chemical leaching over a theoretical smelting process?

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No, I have not yet smelted MLCC's. But I'm now working on a sound hypothesis and trying to improve the process, So I can try it in the near future. I expect a better yield from smelting over Chemical leeching.
If you read the post fully you'll understand what I mean. It is almost impossible to fully claim PM's from MLCC's by Chemical means. The mineral oxides are the cause here.

samuel-a said:

Something is missing. What have you processed exactly?

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High end MLCC's to be exact. 8)

I think we need to talk straight preferably with photos or manufacturer marks(names), model numbers instead of things like High end MLCC's, high yield, mil specs, super high yield, and similar constructions.
What one consider super high yield or high end may not be the case or it is considered as such only by that person and all this only lead others to confusion what we talk about.