# Platinum Recovery From Ceramic Processors



## Tzoax (Jan 28, 2015)

After processing 41 pieces of ceramic Pentium MMX processors with aqua regia and dropped the gold with smb, I decided to cement the rest with aluminum and take the material to XRF test. The results are in the picture 1.


There seems to be a considerable percentage of platinum, so I started to collect the same material from all different types of ceramic processors. Right now I have 135 grams of material from 190 pieces of ceramic processors.
The types and quantity of processors are shown in the table below. I also put in the table the amount of gold that I obtained. I also recovered the gold from lids and get 1.3 grams of gold from 59g of lids (22.03 grams of gold per kilogram of lids or 0.022g of gold per gram of the lids).

Pcs Total gold Avg. by piece Lids Weight /piece
MMX 20 1.1 0.0550 /
MMX 21 1.3 0.0619 /
K6 19 0.7 0.0368 /
AMD 40 1.4 0.0350 /
AMD 20 0.9 0.0450 /
Intel 486 12 1.6 0.1333 1.58
AMD 486 12 1.3 0.1083 0.9
K5(+cap) 7 1.3 0.1857 1.81
IBM 686 9 1.1 0.1222 /
Intel pentium 4 0.8 0.2000 1.77
Intel PRO 4 0.8 0.2000 /
K5(-cap) 4 0.7 0.1750 1.85
Cyrix 686 4 0.3 0.0750 /


There are two exeptions, 40 pieces of AMD and 4 pieces of Cyrix 686 - I made a mistake and I couldn't drop the material with aluminum. So, this 135 grams of material are from all the rest of processors (146 pieces).
On the picture 2 and 3 is the look of actual material pictured with and without a flashlight.




I need help how to continue the process.

My basic idea is to:
1. boil the material several times with destilled water and filter
2. boil the material in HCl several times and filter
3. boil the material several times with destilled water and filter
4. incinerate the material
5. let it react with dilluted HNO3 and filter, (I will save the liquid with silver nitrate for later recovery of silver)
6. aqua regia and precipitate platinum with ammonium chloride

I will post the data with pictures as I working, any suggestion and help is welcome. Thank You.


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## solar_plasma (Jan 28, 2015)

...gramm...kilogramm...€...$...nBananas? Could you please write the units behind your numbers? My eyes are getting older and the numbers look like postal codes.

On the assay there is written "qualitative analysis", does this mean, that the numbers do not say much about the quantity of content, but only show positive or negative?

Does a stannous test confirm any platinum? What part can it come from?


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## Tzoax (Jan 28, 2015)

solar_plasma said:


> ...gramm...kilogramm...€...$...nBananas? Could you please write the units behind your numbers? My eyes are getting older and the numbers look like postal codes.
> 
> On the assay there is written "qualitative analysis", does this mean, that the numbers do not say much about the quantity of content, but only show positive or negative?
> 
> Does a stannous test confirm any platinum? What part can it come from?


Here it is...sorry for the numbers, the space between the numbers was automatically shortened when I posted it.


The results from the test is shown in percentages. It means that there is about 4.5 % of platinum in the material. The sample I tested is from 41 pieces of ceramic MMX. I have 135g of the material, so I hope that there should be about 5-6 grams of platinum.


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## solar_plasma (Jan 28, 2015)

Nice work! Thanks for sharing.

I am sceptic where the platinum should come from. I would take a sample, wash it free of base metals, then treat it by AR and test by stannous. Very small amounts of platinum will give orange color.


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## kurtak (Jan 28, 2015)

Was the XRF test done on powders like you pictured - or on melted metal button/bar :?: 

If it was on powders I would not count on the results being anything you can count on :!: :!: :!: 

Kurt


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## Tzoax (Jan 28, 2015)

solar_plasma said:


> Nice work! Thanks for sharing.
> 
> I am sceptic where the platinum should come from. I would take a sample, wash it free of base metals, then treat it by AR and test by stannous. Very small amounts of platinum will give orange color.


Thank You, eventually I will do that. In the meanwhile I will picture exactly every step that I take. I know that platinum is there in the ceramic processors, the only question is how much... the result should be some middle value of platinum in mixed ceramic processors. At the end I will divide the number of processors I used for the material and the amount of obtained platinum and that would show me the approximate value (Pt) of one mixed ceramic processor. And of course to see if it is even worth processing the Pt from ceramic cpus.


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## Tzoax (Jan 28, 2015)

kurtak said:


> Was the XRF test done on powders like you pictured - or on melted metal button/bar :?:
> 
> If it was on powders I would not count on the results being anything you can count on :!: :!: :!:
> 
> Kurt


I crushed one sample of powder in the very fine powder and that was tested. I know that it is not accurate but eventually i will see how much (if any of Pt) is there.


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## solar_plasma (Jan 28, 2015)

Plausiblity check: Generations of e-scrap prospectors have processed MMX CPU's and no one ever should have discovered the platinum when he checked his barren solution after gold precipitation? But you KNOW it is there. The only thing you KNOW is, that your XRF used on a powder, which it isn't designed for, reported platinum. This could have more than one reason.

That does not mean, there is no platinum. But if it is there, I would bet on other sources, where it came from, then those MMX.


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## solar_plasma (Jan 28, 2015)

How many times "my" ion mobility spectrometer reported VX or chlorine, but it's only a cross sensitivity. Otherwise I would not be able to write this.


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## Tzoax (Jan 28, 2015)

solar_plasma said:


> Plausiblity check: Generations of e-scrap prospectors have processed MMX CPU's and no one ever should have discovered the platinum when he checked his barren solution after gold precipitation? But you KNOW it is there. The only thing you KNOW is, that your XRF used on a powder, which it isn't designed for, reported platinum. This could have more than one reason.
> 
> That does not mean, there is no platinum. But if it is there, I would bet on other sources, where it came from, then those MMX.


Maybe You are right, but I will only know for sure at the end, I will get rid of base elements and try to recover platinum, then the XRF test will be more precise. After all, the XRF test shows that there is no gold, like there isn't because I precipitated it, and that there is a 4.5% of platinum, maybe it is not accurate but thats why I believe there is a platinum, otherwise the mistakes of XRF would be selective and that doesn't make a sense to me. More likely there is some platinum, just my opinion.


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## jungle_Dave (Jan 28, 2015)

Would be interesting to see, hope there is some platinum for you in the material.

Complements on your record keeping as well !


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## Tzoax (Jan 28, 2015)

jungle_Dave said:


> Would be interesting to see, hope there is some platinum for you in the material.
> 
> Complements on your record keeping as well !


Thank You very much. Today I will start to remove the base metals and I will keep You updated.


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## kurtak (Jan 28, 2015)

solar_plasma said:


> The only thing you KNOW is, that your XRF used on a powder, which it isn't designed for, reported platinum.



Solar is correct on this 

An XRF is NOT designed for testing powders - it is designed for testing sold metals & alloys of metals

with powder there are hundreds (or thousands) of surfaces for the ray to bounce off of which confuses it --- at best it will give you an idea of what "might" be in it

Melt a button (or bar) & test that

Kurt


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## AUH-R (Jan 28, 2015)

Is there any reason you used aluminium instead of copper to cement out the precious metals?


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## Tzoax (Jan 28, 2015)

AUH-R said:


> Is there any reason you used aluminium instead of copper to cement out the precious metals?


Thank You, maybe I should use Cu to cement at first place, that way I would have much less unnecessary elements in powder. Thanks, next time I will use copper.


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## Anonymous (Jan 28, 2015)

Tzoax said:


> I also recovered the gold from lids and get 1.3 grams of gold from 59g of lids (22.03 grams of gold per kilogram of lids or 0.022g of gold per gram of the lids).



I would suggest from experience that your yields are on the low side from the ceramic lids. How are you processing these? 

Regards

Jon


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## Tzoax (Jan 28, 2015)

spaceships said:


> Tzoax said:
> 
> 
> > I also recovered the gold from lids and get 1.3 grams of gold from 59g of lids (22.03 grams of gold per kilogram of lids or 0.022g of gold per gram of the lids).
> ...


I process the ceramic lids first with dilluted nitric acid - 50% destilled water, 50% nitric acid, then I filter the foils, then aqua regia and precipitate the gold with SMB. I thought that 22g of gold per kilogram of lids is a good yield. What is Your way of processing it?


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## Anonymous (Jan 28, 2015)

It's a great yield. Until I actually began to process the lids I never realised how good they were. Many people had claimed that the yield was around 6g per Kg and I was assuming that they were correct. I could not have been more wrong.

I'm pretty sure that your way of doing it is perfectly fine too. I put them in AR, and when the reaction has finished (and boy is it vigorous) I pour off the liquid which is barren because the gold has cemented. Then I do it again, and again, (as required until most of the metal is gone) and the final fresh AR solution takes in the gold, with a lot less impurities than trying to dissolve the whole lot into the first solution.

Regards

Jon


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## Tzoax (Jan 29, 2015)

spaceships said:


> It's a great yield. Until I actually began to process the lids I never realised how good they were. Many people had claimed that the yield was around 6g per Kg and I was assuming that they were correct. I could not have been more wrong.
> 
> I'm pretty sure that your way of doing it is perfectly fine too. I put them in AR, and when the reaction has finished (and boy is it vigorous) I pour off the liquid which is barren because the gold has cemented. Then I do it again, and again, (as required until most of the metal is gone) and the final fresh AR solution takes in the gold, with a lot less impurities than trying to dissolve the whole lot into the first solution.
> 
> ...


Thank You, I never tried that way. I tried many times to process the motherboard pins and plactic processors pins that way but only with first solution of AR. Since the ceramic lids have no solder I thought that would be better way.


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## Tzoax (Jan 29, 2015)

Today and yesterday I was boiling in destilled water and filtering the powder, and there seems there is no end, the particles that goes thru the filter eventually settles down, and I dont see that the water is clearer. Obviously the particles are so small that filtering is no option. 
My guess is that it is form of iron chlorides - rust.
I will wait the powder to settle, decant the water and continue with process. 

I was thinking is it a good idea to boil in HCl first, prior the incineration and nitric, and I concluded there is no need for that, the HCl will not dissolve tin because it is not in metal shape, so today I will expose the powder directly to diluted nitric.


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## patnor1011 (Jan 30, 2015)

You are chasing a rainbow.
But it seems you have to do it, it is probably part of your learning curve. 
Did you even try to test it (as was suggested here) with stannous prior throwing time and resources to this adventure?


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## Tzoax (Jan 30, 2015)

patnor1011 said:


> You are chasing a rainbow.
> But it seems you have to do it, it is probably part of your learning curve.
> Did you even try to test it (as was suggested here) with stannous prior throwing time and resources to this adventure?


Unfortunately I haven't test it with stannous for Pt when i dropped the gold at first place. I am planning to do that when i remove base metals and make AR solution at the end. But...there are problems. I removed the most of base metals with nitric and still there is a brown mud floating around, maybe mix of metastannic acid and iron chlorides and it is so hard to filter...I even try to replace regular filters with coffee filters, and the filtering is so slow...several minutes for one drop of solution. This brown mud is giving me much troubles for filtrating, I hope I will finish soon, and incinerate the powder, boil in HCl, make AR solution and test it with stannous. I think that I made a mistake when i had stannic chloride from AR in the powder, I could use alcohol to solute the stannic chloride (which is made when tin is in AR solution) and filter the rest, that way I would get rid of tin before I made problems when making metastannic with nitric that is hard to filtrate. But, there seems there is not much tin there. I think that this brown mud is mostly iron chlorides that is hard to solute even with AR.


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## solar_plasma (Jan 30, 2015)

Don't use alcohol!

You can find thread about how to treat metastannic and red iron oxides (not chlorides, which are soluble) and solve problems with those. I leave it to your learning curve to find those.


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## kurtak (Jan 30, 2015)

solar_plasma said:


> Don't use alcohol!
> 
> You can find thread about how to treat metastannic and red iron oxides (not chlorides, which are soluble) and solve problems with those. I leave it to your learning curve to find those.



Very good advice - listen to it !!!

Kurt


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## Tzoax (Jan 30, 2015)

solar_plasma said:


> Don't use alcohol!
> 
> You can find thread about how to treat metastannic and red iron oxides (not chlorides, which are soluble) and solve problems with those. I leave it to your learning curve to find those.


Ok, thank You very much. For metastannic the incineration will convert it to metal, then HCl will dissolve it. I will take a look for red iron oxides..I had once the same problem when I processed ceramic processors with AR, overheating AR solution creates iron oxides. I will try to find solution on the forum.


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## kurtak (Jan 30, 2015)

Keep alcohol OUT of the lab completely - there is NO use for it in refining

mixing alcohol with acids that have had metals dissolved in them &/or treating the salts/oxides of metals (with alcohol) that don't dissolve with the acid can create explosive compounds - some of them can explode under there own weight & when wet like silver fulminate ( one example)

Kurt


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## Tzoax (Jan 30, 2015)

kurtak said:


> Keep alcohol OUT of the lab completely - there is NO use for it in refining
> 
> mixing alcohol with acids that have had metals dissolved in them &/or treating the salts/oxides of metals (with alcohol) that don't dissolve with the acid can create explosive compounds - some of them can explode under there own weight & when wet like silver fulminate ( one example)
> 
> Kurt


Thank You, I was thinking to add alcohol to powder with stannic chloride, not acid. But, You are right, I will not use alcohol at all, thank You again for advice.


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## solar_plasma (Jan 30, 2015)

Incinerating stannic is one way to go and the most common. Another thread tells about dissolving it by NaOH, which worked fine for the operator. I don't know yet, which one is less work. A good read for sure.


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## Tzoax (Feb 4, 2015)

I finally managed to filter the solution, I've done it with multilayer toilet paper, it was fast and all powder is in it. Tomorrow I will dry it, burn it and I will make AR solution and test it with stannous. I hope that carbon from burnt paper will not cause some problems in AR solution.


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## g_axelsson (Feb 4, 2015)

If you burn (incinerate) the paper properly there should be no carbon left. Carbon can absorb gold chloride from solution.

Göran


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## Palladium (Feb 5, 2015)

The only question you have to ask yourself from an engineering standpoint is why platinum? There's your answer!


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## Tzoax (Feb 5, 2015)

g_axelsson said:


> If you burn (incinerate) the paper properly there should be no carbon left. Carbon can absorb gold chloride from solution.
> 
> Göran


Thank You very much.


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## Anonymous (Feb 5, 2015)

Palladium said:


> The only question you have to ask yourself from an engineering standpoint is why platinum? There's your answer!



Whilst in this particular context I'm with you, do remember that there are plenty of applications of precious metals especially in server equipment that you look at and say "why??!!" 

For example- HP's use of gold to decorate high end motherboards. From an engineering perspective it makes absolutely no sense at all! 8) 8)


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## Palladium (Feb 5, 2015)

From an engineering standpoint it makes perfect sense. Its a high quality product that requires a high level of protection. Cost is not the objective as much as functionally. The added benefit and cost are passed on to the consumer. From their a company can decide if it makes profit. From the engineers view its not about the money but the function of the product. In this instance platinum makes no sense cost or functionally wise.


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## Anonymous (Feb 5, 2015)

Palladium read my post mate- the word "decorate" was used- they decorate the boards- it's not used to anything functional.


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## Tzoax (Feb 6, 2015)

This is the picture of incinerating the toilet paper filled with filtered powder. I've done it on sand. I made powder of it and incinerated again, can anyone tell me can I make AR solution with sand and ashes mixed together with powder, would it cause problems, or there is a better way?


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## kurtak (Feb 6, 2015)

Tzoax said:


> This is the picture of incinerating the toilet paper filled with filtered powder. I've done it on sand. I made powder of it and incinerated again, can anyone tell me can I make AR solution with sand and ashes mixed together with powder, would it cause problems, or there is a better way?



Why in the world did you do your incineration on sand ? --- You have just complicated your recovery processing !

You should do your incineration in a 300 series (non-magnetic) stainless steel pan

When I incinerate my filter papers I start in a SS kettle with a lid on it (so paper doesn't float off in the rising heat) because of the lid on the kettle the paper does not reduce to ash but to carbon instead --- once the paper is reduced to carbon it can be crushed down to a fine powder which is then put in a SS fry pan with out the lid to reduce the carbon to ash

Kurt


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## Tzoax (Feb 6, 2015)

kurtak said:


> Tzoax said:
> 
> 
> > This is the picture of incinerating the toilet paper filled with filtered powder. I've done it on sand. I made powder of it and incinerated again, can anyone tell me can I make AR solution with sand and ashes mixed together with powder, would it cause problems, or there is a better way?
> ...



Thank You, the wet papers was very wet and heavy, I had to dry off it first. Because there was much water inside papers I thought it would be best to make it dry first on a electric hotplate with sand. After 3 hours papers finally dried off, then it was too late to replace it because some parts started to red glow and I left it until all turned to carbon. I haven't consider that sand will make some problems after in AR. So, now I have mix of sand, ashes and powder.


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## lanfear (Feb 6, 2015)

If these were the fiber type MMX CPU's there is some type of mmlc on them that can contain traces of Pd.


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## Tzoax (Feb 6, 2015)

lanfear said:


> If these were the fiber type MMX CPU's there is some type of mmlc on them that can contain traces of Pd.


Thank You, these are all ceramics, and even those AMD processors (socket 462) and K6 that contains palladium and platinum in MLCC was removed before processing.


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## kurtak (Feb 6, 2015)

Tzoax said:


> Thank You, the wet papers was very wet and heavy, I had to dry off it first. Because there was much water inside papers I thought it would be best to make it dry first on a electric hotplate with sand. After 3 hours papers finally dried off, then it was too late to replace it because some parts started to red glow and I left it until all turned to carbon. I haven't consider that sand will make some problems after in AR. So, now I have mix of sand, ashes and powder.



Tzoax

If the sand was a "very clean" silica sand doing an AR leach can still be done - the complication is that now you have to use a greater amount of HCl in making up your AR in order to cover the sand as well as the ash & metal powders --- because you are going after PGMs the leach solution needs to concentrated acid & not diluted (at least not to diluted if you are talking Pt) so you will be using more acid then other wise would have been needed --- this of course means creating more waste

Also filtering/washing all the solution out of the sand has become a greater problem - still do-able its just going to take a greater volume of water (& I hope you have a vacuum filter set up or you wont get it all washed out) this means a "huge" increase & dilution of you leach solution which in turn means a huge amount of evaporation to concentrate your solution back down before recovering your PMs

& that's if the sand is a "very clean" silica sand (which it does not look like)

On the other hand if its dirty sand - with clay in it &/or organic material &/or the sand its self is made up of mineral matter other then silica the "potential" problems have become much more complicated --- all of which would take far greater time to explain then I have time for

Kurt


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## Tzoax (Feb 6, 2015)

kurtak said:


> Tzoax said:
> 
> 
> > Thank You, the wet papers was very wet and heavy, I had to dry off it first. Because there was much water inside papers I thought it would be best to make it dry first on a electric hotplate with sand. After 3 hours papers finally dried off, then it was too late to replace it because some parts started to red glow and I left it until all turned to carbon. I haven't consider that sand will make some problems after in AR. So, now I have mix of sand, ashes and powder.
> ...


Thank You for explanation. The sand wasn't silica, I used plain river sand, Most likely organic dirty. I thought that incineration will take out all organic material and that sand will not cause problem in AR. After all, even if I loose some platinum this way #if there is any# the most of it should go into solution, and at least I could test it with stannous to see if it is present. There is not that much sand in it, I will not need much acid. 
Now I will wash it with water and let it settle one day, then I will decant it and make AR solution, test with stannous and see if there is any platinum in there. I forget to say that all types of ceramic processors that I used here that contained any smd component like MLCC or resistors that contained Pt and Pd was previously removed with heatgun, so if there is a Pt it was most likely inside of the prosessors.


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## ericrm (Feb 7, 2015)

why dont you simply take your incinerated material + the sand that close to it than incinerate this material again to white ash? this way you will make sure that everything is by the book. since your doing yield test you shoulnd left anything to the unknow... after all if the result isnt what you expected you will know that yo0u have done everything correctly


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## Tzoax (Feb 7, 2015)

ericrm said:


> why dont you simply take your incinerated material + the sand that close to it than incinerate this material again to white ash? this way you will make sure that everything is by the book. since your doing yield test you shoulnd left anything to the unknow... after all if the result isnt what you expected you will know that yo0u have done everything correctly


Thank You, thats exactly what I will do.


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## Tzoax (Feb 26, 2015)

I've made a brand new AR solution of ceramic processors and tested with stannous. The result was negative. So, there is no platinum in ceramic processors and if so, there is a very small quantity. Obviously the xrf scanner is not precise with the powders. Next time when i go check the xrf results, it will be from alloy.


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## g_axelsson (Feb 26, 2015)

So the 5% Pt in this analyze wasn't there in the end. Do you still trust the result you posted about the MLCC powder left over after AR dissolving?

I sent out some mineral samples to a lab in Russia a number of years ago, but I stopped with that when I got results back that could not be correct. Either they mixed up my results with some one else results or their methodology was flawed. Either way, I could not trust anything that I couldn't verify myself so it was the end of using that lab.

XRF can be a very powerful tool, but if the operator doesn't understand how to use it or the instrument isn't programmed for that kind of materials then the results can be very wrong.

From the analyze it looks like the instrument is only programmed to read precious metal alloys and if it doesn't take into account the effect of contributions and absorption from non-metal elements there will be huge errors in the result.

Göran


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## Tzoax (Feb 26, 2015)

g_axelsson said:


> So the 5% Pt in this analyze wasn't there in the end. Do you still trust the result you posted about the MLCC powder left over after AR dissolving?
> 
> I sent out some mineral samples to a lab in Russia a number of years ago, but I stopped with that when I got results back that could not be correct. Either they mixed up my results with some one else results or their methodology was flawed. Either way, I could not trust anything that I couldn't verify myself so it was the end of using that lab.
> 
> ...


I was wrong, so my platinum fever is over.  
And if I test alloy of anything the results of xrf should be relevant? Or even then it could be unaccurate?


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## FrugalRefiner (Feb 26, 2015)

Tzoax said:


> g_axelsson said:
> 
> 
> > So the 5% Pt in this analyze wasn't there in the end. Do you still trust the result you posted about the MLCC powder left over after AR dissolving?
> ...


As Göran said, if the person using the XRF doesn't know what he's doing, or if the machine isn't calibrated for the types of metals in your sample, the results can still be inaccurate.

Dave


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## MarcoP (Feb 26, 2015)

But what about palladium, isn't it used for bonding ceramics?


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## patnor1011 (Feb 26, 2015)

Probably not. What I have seen was AgPd alloy used for bonding in some IC packages. As far as I remember they were called Rabbit but I do not remember exact type. Like these - with pins on all 4 sides. 
http://www.datasheetdir.com/package-TFBGA


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## MarcoP (Feb 26, 2015)

Thanks Pat. After a quick search I found palladium it's used in frames in place of lead and in other applications palladium-ceramic it's used to hold heat, in the latter would off course not be good for processors lids.


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## g_axelsson (Feb 26, 2015)

Just to clarify for those that reads this thread. When they are talking about lead frames, it's the metal strip with punched out leads that they mount the die on and connect the bond wires to. It's not the metal lead.
After the die is brazed to the lead frame and the bond wires bonded the whole package is molded in plastic and the legs cut off from the metal strip. Then the chip is ready for soldering.

Göran


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## MarcoP (Feb 26, 2015)

g_axelsson said:


> Just to clarify for those that reads this thread. When they are talking about lead frames, it's the metal strip with punched out leads that they mount the die on and connect the bond wires to. It's not the metal lead.
> After the die is brazed to the lead frame and the bond wires bonded the whole package is molded in plastic and the legs cut off from the metal strip. Then the chip is ready for soldering.
> 
> Göran


Thank you Göran for the great explanation, the following is the quote of the text where I've found that information. I still can't understand how a plating can replace a welding. I haven't searched more and will probably have more time in the next few days.



http://www.stillwaterpalladium.com/electronics.html said:


> Lead frames are used to connect integrated circuits to other electronic devices. Some manufacturers use palladium to plate the frames as an environmentally preferable alternative to tin-lead solder.


Marco


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## g_axelsson (Feb 27, 2015)

MarcoP said:


> g_axelsson said:
> 
> 
> > Just to clarify for those that reads this thread. When they are talking about lead frames, it's the metal strip with punched out leads that they mount the die on and connect the bond wires to. It's not the metal lead.
> ...



There is no welding in that quote. (welding = melting the base metal, brazing = high temperature soldering, soldering = connecting two object by another melted metal but the base isn't melted.)
The tin-lead solder mentioned is the plating on the legs of the chip. By substituting it against palladium plating the base metal is still protected from oxidation and can still be soldered without problems.

Göran


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## MarcoP (Feb 27, 2015)

Now that make sense, thank you! I just realized that in english welding and soldering refer to two different techniques while in my mother language there is only one word for it. Now I can start paying attention to those differences. Thanks to you I've just improved my english 

Marco


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## g_axelsson (Feb 27, 2015)

My pleasure! 8) 

Göran


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