Best method for the small BGAs on ram?

[mysticrey2414]

Hi, I apologize as I’m sure this question has been answered somewhere but I can’t seem to find it. What are your personal preferences on processing the BGA chips that are found on ram?

 

[Yggdrasil]

Hi, I apologize as I’m sure this question has been answered somewhere but I can’t seem to find it. What are your personal preferences on processing the BGA chips that are found on ram?

The general concesus is to pyrolize, incinerate and gravity separate.

 

[kurtak]

The general concesus is to pyrolize, incinerate and gravity separate.

Before all of that you also need to do HCl soak/leach to remove the tin from the solder balls on the bottom of the chips - if you don't get rid of the tin before the rest of the processes it will cause nothing but problems all the way down the line with all other parts of the process

So quick answer

1) HCl soak/leach to remove tin

2) pyrolize/incinerate to turn plastic/epoxy to carbon/ash

3) mill to crush carbon/ash to fine powder

4) sift milled powder through at least 80 mesh screen

5) concentrate (bond wires) by washing much/most of carbon/ash (that goes through 80 mesh screen) by panning or running on concentrator table

6) re-incinerate concentrates to insure all carbon is turned to ash

7) you then have the option to ether leach the gold (bond wires) out of the concentrate with AR - or - smelt the concentrates to recover the gold from the concentrates

Kurt

 

[Taleeho]

Can I use the dissolved Tin from HCl leach to make stannous chloride gold detection test solution?

 

[Yggdrasil]

Can I use the dissolved Tin from HCl leach to make stannous chloride gold detection test solution?

Welcome.
It is actually already a Stannous, but without control of how clean it is it is hard to say if it is suitable.
Try it with a standard Gold solution.

 

[Christian333]

Taleeho,

I've made stannous with BGA solder balls, it worked.

Janie

 

[Taleeho]

Which CPU type PGA, LGA, or BGA has more gold?

 

[Ayham Hafez]

Since you asked for the best, that mean you have to smelt.

Since many years I was processing different ic chips with hydrometallurgy process, but after I tried smelting, I regretted for each single time I didn't smelt, so from my experience, the best way to process high yield ic chips such as RAMs ic chips is:

1- leach in HCl or dilute nitric to get rid of tin
2- pyrolizing the ic chips
3- grinding the ic chips
4- fluxing the ic chips powder then smelt, usually I add 10% copper wire as a collector metal since I don't make any kind of concentration to reduce the carbon content, no need to incinerate before smelting. For fluxing you can only use 1 part borax, 2 parts soda ash and some flour spar.
5- pour the ic chips alloy and start use hydrometallurgy method for processing, like parting gold with nitric acid leaching.


With smelting, the fault tolerance is very high, rather than dealing with a lot of ash by chemicals, you only treat small metal alloy, also you can see with your eyes what's happening with your gold and other metal parts, so it's easy to know when base metals dissolved and when gold fully hydrated etc...



Thanks for the forum members that gave me the knowledge of smelting.

 

[Taleeho]

Since you asked for the best, that mean you have to smelt.

Since many years I was processing different ic chips with hydrometallurgy process, but after I tried smelting, I regretted for each single time I didn't smelt, so from my experience, the best way to process high yield ic chips such as RAMs ic chips is:

1- leach in HCl or dilute nitric to get rid of tin
2- pyrolizing the ic chips
3- grinding the ic chips
4- fluxing the ic chips powder then smelt, usually I add 10% copper wire as a collector metal since I don't make any kind of concentration to reduce the carbon content, no need to incinerate before smelting. For fluxing you can only use 1 part borax, 2 parts soda ash and some flour spar.
5- pour the ic chips alloy and start use hydrometallurgy method for processing, like parting gold with nitric acid leaching.


With smelting, the fault tolerance is very high, rather than dealing with a lot of ash by chemicals, you only treat small metal alloy, also you can see with your eyes what's happening with your gold and other metal parts, so it's easy to know when base metals dissolved and when gold fully hydrated etc...



Thanks for the forum members that gave me the knowledge of smelting.

Could you please describe how you pyrolyze the chips like how to heat and how hot to get? Thanks

 

[Ayham Hafez]

Could you please describe how you pyrolyze the chips like how to heat and how hot to get? Thanks

I used my home made pyrolyzer, but it process large quantity, you can use any pot that has lid, close it tightly and you can use some refractory paste like mixing sodium silicate with some cement and put it between the pot and the lid, lid should has a small hole to make smoke go throw while heating, maybe you can connect a long tube and put it in water bucket so smoke will be cooled and decomposed, after that you can make seperator from plastic bottle to separate gas from oil, gas can be used again to heat the pot

 

[Yggdrasil]

I used my home made pyrolyzer, but it process large quantity, you can use any pot that has lid, close it tightly and you can use some refractory paste like mixing sodium silicate with some cement and put it between the pot and the lid, lid should has a small hole to make smoke go throw while heating, maybe you can connect a long tube and put it in water bucket so smoke will be cooled and decomposed, after that you can make seperator from plastic bottle to separate gas from oil, gas can be used again to heat the pot

Ideally the smoke/gases go back into the fire to become combusted/burned, an added bonus is that this will reduce the use of gas.
And the exhaust will be cleaner.

 

[Michael Banyai]

Is there another name or composition of the "flower spar" noted in the fluxing answer?

 

[Yggdrasil]

Is there another name or composition of the "flower spar" noted in the fluxing answer?

Welcome to us.
When dealing with chemistry it is important to use the correct naming, and there is no such thing as "flower spar"
There are however Fluor Spar or Cryolite, which thins the slags during the smelting.

 

[FrugalRefiner]

I'm guessing you mean fluorspar. As a mineral, it is fluorite. Chemically, it is calcium fluoride.

Dave

 

[Michael Banyai]

Yes, I suspected that there had to be a proper name as I did not reconize what the other poster said, thanks

 

[Yggdrasil]

Yes, I suspected that there had to be a proper name as I did not reconize what the other poster said, thanks

I suspect you are using videos for this?
Much better to find books or read the forum.
There are few videos out there that can be trusted.

 

[Michael Banyai]

I find your comment above to be presumptive, jaded, even somewhat rude. There was nothing in my question to indicate an unwillingnees or inability to do proper research. I even put the phrase in question in quotation marks to indicate that it was not my origional phrase. I have actually read cover to cover Hoke a number of times and used the forem for research from time to time. I am in fact well grounded, haveing passed through inorganic and organic chemistry as well as quantative and qualitive chemistry while still in high school 55 years ago. A number of advanced scientific degrees followed. As Moderator I guess you get tired of folks who do not try to do research before questions, but it would pay to be a bit more respective, and humble to us that in fact have done everything correct as far as trying to gain understanding of something that was unclear. I do in fact aplaud your willingness to help others as a moderator..with good cheer....

 

[Yggdrasil]

I find your comment above to be presumptive, jaded, even somewhat rude. There was nothing in my question to indicate an unwillingnees or inability to do proper research. I even put the phrase in question in quotation marks to indicate that it was not my origional phrase. I have actually read cover to cover Hoke a number of times and used the forem for research from time to time. I am in fact well grounded, haveing passed through inorganic and organic chemistry as well as quantative and qualitive chemistry while still in high school 55 years ago. A number of advanced scientific degrees followed. As Moderator I guess you get tired of folks who do not try to do research before questions, but it would pay to be a bit more respective, and humble to us that in fact have done everything correct as far as trying to gain understanding of something that was unclear. I do in fact aplaud your willingness to help others as a moderator..with good cheer....

There was no rude intent in my statement, just the cold facts.
Take it as you wish.
And yes, we get tired of the same questions over and over again, especially when so little is needed to find what one need.
We try as good as we can in general terms for all newcomers, but as these new digital arenas make all and everything available to everyone's fingertips, they are not well suited to convey emotions, attitude and so on.
And unless you say so, we can not see who has training or not.
And believe me, not all well trained people take this topic easy.
Well today's rant over and welcome again.