# removing solder from pins HCI



## TEB

Hello.

I stripped around 20 motherboards to play with, I removed all the pins with a blow torch and other various parts. 
As a test i pried out around a handfull of pins from the plastic surrounds, There was still a fair amount of solder left on them. I read the the solder could be removed with HCI so i got a glass jar and pored in some HCI about 20min later ild say most near all the solder was gone. Though the pins look greay with no gold left. So i pulled out a few pins and gave them a rub to see if this was just a surface coating of solder and other metals. 
Ild say that it was tarnished with the other metals, though what gets me is it seams that near all the gold has also been stripped, as i can see through it in most places and its nowhere near as shiney.

i dont get it how do i process these pins off the motherboard, and can they be processed in the plastic casings.
Sorry i know this would bound to be on the site though i can find it and am confused.

thanks


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## patnor1011

Not a lot of people process them. It is because all that you encountered in your experiment. It is very labor intensive to cut them off board but it saves you time and chemicals later when you process them. If you use heat gun and desolder them from boards you get a lot of tin on them. 
I would try to separate them in two types. You can see that here: http://www.goldrefiningforum.com/phpBB3/viewtopic.php?f=33&t=6169
They are cut out to minimise amount of solder. I can think about two types of extraction. One is gold cell where they will be stripped in copper basket and second is (good for small pins which may not be good for basket) crock pot whith HCl. Your test just showed you how to do that but in order to get values, you need to leave them in HCl for considerable amount of time to have them completelly dissolved. You can speed up that process little bit by using crock pot, and small very small amount of oxidizer like peroxide. 
You can use Nitric for dissolving base metals too, do not add HCl as you may create AR and dissolve everything. When you dissolve base metals proceed to incinerate foils and powder to get rid of traces of Nitric and wash with HCl.
Lot of chemicals and time involved but it can be done.
Do not try to process pins with plastic holders in acids as you may end up with big mess as some plastics do not like acid baths :mrgreen:


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## patnor1011

All this is on forum already so if you want to see processes or some yields or problems encountered please do yourself a favor and try to explore this forum. All your future questions were answered at some points and everything is perfectly explained in Hokes book you can download that from my signature. You need to sit down and invest your time in gaining knowledge first if you want to be successfull in this field. There are too many variables involved in processes and you need to gain knowledge to be able to choose the right path to solve any problem which you may encounter.


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## TEB

Thankyou for the informaion and the links, i will read it all.
I put them back in the HCI and it is still removing metals showing the gold more, though like you say its a lot of effot for little return.

though im not about to quit, just need more information i guess, cheers for the links again.


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## lazersteve

What type of motherboards did you strip? The pins off of PIII and newer motherboards are most likely only flash plated and hence a total waste of your time.

You should look at processing a few hundred grams of fingers as your first test batch, not motherboard header pins.

Steve


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## TEB

roughly 
1 x 486
4 x p2
5 x p3
8 x p4

after a good look at it today,it seams that like you said its mostly flash plated and very thin. there are a few good ones in there i guess they are from the 486 and p2, i have just over 100gms of these pins so i will just put them aside to i get a lot more and a better understanding.

I have about 100gms of clean fingers of slot cards and if i clean up some of the ram i guess 150gms, though some of the older ram i had is gold printed under the green mask. and the rest is like any other still with a few spots and gold solder for the chips. so i look into these more today.

i tryed to read some of the things that patnor1011 has in his signature though i lost intrest quickley without pictures. I like to get my hands dirty 1st and lean as i go. Steve i think they are you videos i wached and they where great. Vidoes and pictures and good 

i might wait to i strip another dozen or two computer before i get anthink worth refining. Ill keep trying though.


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## lazersteve

As a learning process you can process a few hundred grams of finger boards in a quart sized mason jar. Make sure the fingers are trimmed close with minimal green board along the cut edge and no tiny spare parts or pins on the boards!

Do this in a well ventilated area away from metals items that can corrode easily.

1. Place the clean fingers in the jar so they stand upright (long ways) and fit loosely (not tightly packed).
2. Fill the jar up to the top of the fingers with 31.45% HCl (muriatic acid) from Lowes.
3. Add two caps full of 3% Hydrogen peroxide from Walmart or your local drug store.
4. Stir the solution with a glass rod to mix in the peroxide. 
5. Wait one hour and observe the color of the solution. 
6. If the solution is pale light blue repeat steps 3 through 5.
7. If the solution is emerald green, let it sit *covered* overnight (24hours), stirring occasionally if desired.
8. Using plastic tweezers, remove any finger boards that become 100% stripped of all copper (and gold foils) during the next 24 hours, spraying them off into the solution as you remove them. The foils all should be settling to the bottom of the jar, fight the urge to try to pull them out until you are done. Too much water is not desirable, so keep your rinsing to a minimum. 
9. When all of the boards have been stripped, let everything settle and siphon off the liquid.
10. Wash the foils with several rinses of HCl, stirring, settling, and siphoning with each rinse, until the rinse acid is free of color.
11. Wash the foils with two flushes of clean water, stir, settle, and siphon with each rinse.
12. Process the foils with HCl-Cl in the same jar for highest purity.

Post some photos of your experiments and results!

Steve


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## TEB

Steve, I have done what you has sugested and run the small batch of finger i had.

There are a few things in the process that i used that i think need changing for future batches, more along the lines of what you have in your video. 

Its been about 36hrs and about half of the fingers are 90-100% stripped. There are a few that have not seem to be affected at all though time will run its course and prove everything out for me.

What is happening here? 
The solution at 1st turns a pale yellow colour, Knowing that nothing is what it seams when in dulute solutions. Im not ready to jump on saying this is gold though it well could be.
A few of the Pcb's have had the green solder mask removed. so this leads be to thinking that the solutions is at least at a very small scale breaking the surface layers of the Pcb itself, at very least attacking a component used in the mask construction. 
(And what reminds me of a plating solution i done with vinagar and hydrogen proxide prity much the same as here. )
The solution is attacking the copper though this is where i kind of start questining everything, Part of this looks as a simple answer where the gold is printed onto a copper layer and the solution is either leaching through the poures of the gold of the pcb or somewhere attacking this layer of copper when this copper enters the solutions the gold simpley flakes away.
The second theory is the gold is in the relm of 70-80% pure and copper is used as the buffing material. the solution is pulling at the copper and each time it pulls a bit of copper it rejects some of the surounding gold from it bond to the metal allowing it to flot away.
Time will show the next questing more though ill put it up now.
if the pbc has the gold directly printed on the pcb with some kind of glue flux and the gold is closer to the 100% pure, the solution has no copper to pull so this does not allow the top two theorys to hold and the gold should stay attached to the pcb, unless it is attacking some type of flux layer. this or the lack of time could explain why some of the fingers look to not be affected.

i havenot documented the experement very well, though will post a few images where the process is finished.

thanks again.


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## Barren Realms 007

TEB said:


> Steve, I have done what you has sugested and run the small batch of finger i had.
> 
> There are a few things in the process that i used that i think need changing for future batches, more along the lines of what you have in your video.
> 
> Its been about 36hrs and about half of the fingers are 90-100% stripped. There are a few that have not seem to be affected at all though time will run its course and prove everything out for me.
> 
> What is happening here?
> The solution at 1st turns a pale yellow colour, Knowing that nothing is what it seams when in dulute solutions. Im not ready to jump on saying this is gold though it well could be.
> A few of the Pcb's have had the green solder mask removed. so this leads be to thinking that the solutions is at least at a very small scale breaking the surface layers of the Pcb itself, at very least attacking a component used in the mask construction.
> (And what reminds me of a plating solution i done with vinagar and hydrogen proxide prity much the same as here. )
> The solution is attacking the copper though this is where i kind of start questining everything, Part of this looks as a simple answer where the gold is printed onto a copper layer and the solution is either leaching through the poures of the gold of the pcb or somewhere attacking this layer of copper when this copper enters the solutions the gold simpley flakes away.
> The second theory is the gold is in the relm of 70-80% pure and copper is used as the buffing material. the solution is pulling at the copper and each time it pulls a bit of copper it rejects some of the surounding gold from it bond to the metal allowing it to flot away.
> Time will show the next questing more though ill put it up now.
> if the pbc has the gold directly printed on the pcb with some kind of glue flux and the gold is closer to the 100% pure, the solution has no copper to pull so this does not allow the top two theorys to hold and the gold should stay attached to the pcb, unless it is attacking some type of flux layer. this or the lack of time could explain why some of the fingers look to not be affected.
> 
> i havenot documented the experement very well, though will post a few images where the process is finished.
> 
> thanks again.




HCL will turn yellow when introduced to air. It dosen't mean you have gold in your solution.

The pin's that you seen no reaction on are likely kovar.

Most likely your solution will attack the copper base metal before it attacks the gold plating. And gold is not painted on it is plated onto items.


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## lazersteve

If the solution turns dark chocolate brown or black or you see a sediment of gray powder let me know.

Be sure you don't have the finger boards packed too tightly in the jar. The boards tend to shield each other.

If your solution is dark brown, add a 10-20 mL of HCl. Followed by two more caps of 3% H2O2.

I purposely instructed you to use a minimal amount of peroxide to keep you from over doing it and dissolving the gold.

A light blue to emerald green solution is optimal.

Copper chloride can appear yellow in dilute solutions. You need to have stannous on hand to be certain you are not dissolving gold.

Could you post a photo of the results so far?

Steve


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## TEB

I think its all working alright. i have another image of the weigh-in though its on the cameras memory and i need the cable. though its just a kitchen scale in increments of 29gms  

i dont have any stannous on hand, unless i can make some. ill look into this more. so i will not dispose of anything as yet.

its a dark emerald green colour, i was thinking that some of the fingers where not releasing at all. though after lots of agitation they are comming off. up untill this point i was just stiring every hour as they are tightly packed.

i know everything is crude. though a good test i think.
thinking that at this point i can get my hands on 15-30 computer a week without trying though it would be great to get some good scrap. Ebay seams like its all overpriced and slim pickings. i see most auctions, people wanting around the same price as recovered gold for their wares. so ill probley stick to the computers and wait to i get a good stock pile.

///
colour





everything in the jar




removing and washing the stripped pices




The striped pices there is a flake or two that are not 100% removed though what the hell good enough for this test




the fallen gold of the washed pices





cheers

edit.
if the Tin(II) fluoride show that there is gold in solution, am i correct in thinking if a few small pices of copper are placed in the solution will edventually become staurated with copper sulfide and push out the gold.


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## lazersteve

Looks like you are ready for the final clean up with HCl and onto dissolving with HCl-Cl to make the gold chloride solution and precipitate with SMB.

Very good!

Let me know if you want more details on the final steps to your first BB.

Steve


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## TEB

i have had to dump a handfull back in to the solution.

Steve thanks for your help, you rock for being so dedicated and helping so many folks out.

Ill watch your video again so it shold be good.


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## lazersteve

TEB said:


> if the Tin(II) fluoride show that there is gold in solution, am i correct in thinking if a few small pices of copper are placed in the solution will edventually become staurated with copper sulfide and push out the gold.



You were doing so well until you posted this, but I understand your enthusiasm with all this new excitement :lol: .

Please follow along as directed so that you will meet with success and have your first gold BB to show for you devotion and patience. Going through the paces slowly on a small scale will give the insight and confidence to move on to the more complicated scrap types and to apply what you have learned from your earlier observations to succeed with them.

Tin *Chloride* (aka Stannous Chloride) is what we use to test for gold dissolved in a solution. There is a link to a recipe in my signature line below, we will get to that in due time. No need to think of saturating the solution with copper *chloride* anytime soon as the emerald green solution you have is reusable as it is with a little additional air.

If you get antsy please take the time to read the Guided Tour Link below to occupy yourself before jumping ahead.

Steve


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## TEB

removed to new thread


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## voeckel

We are talking about 30+% of HCl concentration. Is there a point where the acid would be too weak to work? I could get here 5L bottles of 20% HCl very cheap (fre of any other ingredients, only HCl and H2O) but i am not sure if it could be used?

If i would multiply the amount of 20% HCl by 1,5, i would get the same amount of substances as the 30% HCl, but what about the excess H2O?

Beginner's question, i know...

Thanks in advance!


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## Geo

many members can only get 15% hcl where they live and from what ive read, it seems to work just fine.


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## patnor1011

I can confirm that. Even only 10% and it worked charm.
I try to get at least 15% one and I boil it down to 50% of volume and use it in AR, also without slight problem.


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## voeckel

Thanks gents. Any experience with time values? I.e. half the concentration needs three times as long, etc?

just curious but it would complete my picture of what to expect.


By the way, patnor, i saw a thread somewhere where you should two CD/movie download links regarding PMs in Ireland but they were not working anymore. Are these still available somewhere? Can't find the post anymore.


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## patnor1011

You probably mean gold in ireland cd, I do have it somewhere and when I find it I will upload it somewhere.


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## freechemist

Hi voeckel,

You say:

_"I could get here 5L bottles of 20% HCl very cheap (fre of any other ingredients, only HCl and H2O) but i am not sure if it could be used?"_

Sure, this acid can well be used. It's composition corresponds to that of constantly boiling azeotropic HCl, and it may well be, that these 5L bottles you are talking of, contain azeotropic HCl, obtained by distillation of a more diluted, raw hydrochloric acid, probably already used in a different process, recovered in a more concentrated form as the known azeotropic HCl by a simple distillation process.


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## voeckel

Thanks freechemist, and sorry for the late reply here. 
I am quite busy at the moment, preparing a trip to go abroad. Hence, I am not that much in the forum at the moment.

I hope to come back with some very good stuff to process and then: hands on experience!


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## voeckel

patnor1011 said:


> You probably mean gold in ireland cd, I do have it somewhere and when I find it I will upload it somewhere.




Hi Patnor,

Yes, those are the ones I meant, sorry to you as well. Your post is even older.

BTW: I will be flying to Dublin on Wednesday to get some things sorted out up there with BOI, flying back home on Saturday. Would be cool to run into you, if you are from up there somewhere.

Peter


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## patnor1011

Awww another month passed... :mrgreen: 
I will make sure to do it in next few days. I am bit busy now this week - working every night. I would like to meet for a cup of coffee but Dublin is 200km far from me and no chance of me going there this week.


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## grfphil

Thanks steve for your post. I'm repeating step 3 now on another test batch. It seems to look like you describe so far!


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## dfrog1983

Hi everyone, I'm just getting familiar with AP ran 5 different very small test batches to get acquainted test 1 had fingers off of about 20 boards, test 2 had 5CPU's, test 3 had the female CPU pins off the mother boards, test 4 had all the other plated pins off the mother boards, and test 5 had two older sticks off ram, I started with a 3:1 HLC to peroxide mix on all 5 test; test 1, 3, an 5 after one hour turned a nice emerald green, test 4 turned a pale green, test 2 immediately bubbled, fizzed and made a white cloud after an hour the liquid was clear, in test 1, 3, and 5 I left them sit stirring occasionally, test 4 I added a little more peroxide hoping to jumpstart the process and have left it sit stirring occasionally, test 2 I added a little more HCL and a capful more of peroxide an hour after that it as a nice emerald green. when I checked them this morning I have noticed that most of the foils in test 1 have come off, most the pins in test 2 have come off and all the foils in test 5 have come off, test 3 about half the starting mass has dissolved but I can still see more needs to dissolve, test 4 is still a pale green with minimal change to the pins; test 1,2,3, and 5 have all turned an extremely dark green with a hint of brown, I actually have taken the two ram sticks (which were broke in half to fit in the mason jar) and rinsed them. the pictures below are of the rinse water, the cleaned ram, and the acid mix.








I hope those loaded right, I have other pictures but until I get the time to create a online album to link to so that I don't increase the cost of the web site to greatly I was just posting a few images from the test that's doing the best, I figure test 1 and 2 will be ready to move to the next step today or tomorrow, while test 3 still needs a few more days in AP and I think test 4 needs filtered, cleaned, incinerated to get rid of any excess acid and then remaining metals put aside till I move on to learning another process as AP is not a good process for those pins, but that was the point of these small test, reading about something and seeing the actual differences are two totally different ways of learning and I'm more a hands on kind of learn so even though my research told me that those pins would react the way they did I still wanted to compare it to the other test. Most the foils from this test as well as test 1 & 2 which have all had the fingers, ram, and CPU's removed left most of their foils and pins in the AP solution. If I'm understanding this correctly I need siphon all the AP solution off and wash the foils before processing with HCL-CL should I also after first process of HCl-CL then rewash the precipitate and reprocess with HCL-CL before melting for a higher purity or is this second processing going to just be redundant?
Thank You in advance for your wisdom in this.


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## jure

lazersteve said:


> As a learning process you can process a few hundred grams of finger boards in a quart sized mason jar. Make sure the fingers are trimmed close with minimal green board along the cut edge and no tiny spare parts or pins on the boards!
> 
> Do this in a well ventilated area away from metals items that can corrode easily.
> 
> 1. Place the clean fingers in the jar so they stand upright (long ways) and fit loosely (not tightly packed).
> 2. Fill the jar up to the top of the fingers with 31.45% HCl (muriatic acid) from Lowes.
> 3. Add two caps full of 3% Hydrogen peroxide from Walmart or your local drug store.
> 4. Stir the solution with a glass rod to mix in the peroxide.
> 5. Wait one hour and observe the color of the solution.
> 6. If the solution is pale light blue repeat steps 3 through 5.
> 7. If the solution is emerald green, let it sit *covered* overnight (24hours), stirring occasionally if desired.
> 8. Using plastic tweezers, remove any finger boards that become 100% stripped of all copper (and gold foils) during the next 24 hours, spraying them off into the solution as you remove them. The foils all should be settling to the bottom of the jar, fight the urge to try to pull them out until you are done. Too much water is not desirable, so keep your rinsing to a minimum.
> 9. When all of the boards have been stripped, let everything settle and siphon off the liquid.
> 10. Wash the foils with several rinses of HCl, stirring, settling, and siphoning with each rinse, until the rinse acid is free of color.
> 11. Wash the foils with two flushes of clean water, stir, settle, and siphon with each rinse.
> 12. Process the foils with HCl-Cl in the same jar for highest purity.
> 
> Post some photos of your experiments and results!
> 
> Steve



hello, 
i have one question :
3. Add two caps full of 3% Hydrogen peroxide from Walmart or your local drug store.
how much is two caps full in ml 

thanks.


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## butcher

The cap full is referring to the lid (or cap) on the bottle of 3% hydrogen peroxide.

This is just a guess on volume, (cap full is probably close to 5 ml of H2O2), so for a quart of HCl (approx 950ml HCl) add about 10ml of 3% H2O2 to get reaction started.


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## Pantherlikher

I just last week had this technical conversation.

Using only a splash of Peroxide just to get the reaction started.
Technically speaking as it came to be is 5ml to any volume of HLC should be enough to get copper to dissolve and get the process to begin. Once started, the copper chloride(II) will continue converting copper untill it is all used up.

Give it a go and you will see you will no longer need peroxide. Just keep alittle solution when it gets full, you will see it, and add more HCL.

B.S.


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