# Boards soaked in hcl



## bcgold (May 20, 2019)

Hcl takes up the nickle plating under gold plated pins, takes up tin leaving the silver behind as a sludge small surface caps smaller than fly sheet fall off.

On the first load used electrolysis to plate out the tin, second and third load just used scrap aluminum to recover the mossy tin which is so full of hydrogen bubbles it floats. I add a bit of fresh hcl to replenish the weakened acid.

This leaching process was done outdoors with out heat, If I do this again will make a vessel that can be heated the biodiesel shops sell a nice barrel blanket for this purpose.

Top two images are of the slime's recovered from the bottom of my vessel, bottom image small caps.


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## bcgold (May 20, 2019)

Incinerated black slime's 146.9 grams.


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## bcgold (May 20, 2019)

Those tiny surface caps that fell off during the soaking, 239.8 grams incinerated then crushed.

The Pyrex container with surface caps has way less material in it than when I had the slime's in it and the weight is near double.


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## bcgold (May 23, 2019)

Never as expected.


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## kurtak (May 24, 2019)

bcgold said:


> Never as expected.
> 
> l1.png
> 
> l2.png



So what was not expected :?: 

And as important (if not more important) what WAS expected :?: 

Showing a pic of a bunch of sludge in a filter & a green solution in a beaker does not tell us a lot :?: :?: :?: :roll: :? :shock: 

Kurt


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## anachronism (May 24, 2019)

kurtak said:


> bcgold said:
> 
> 
> > Never as expected.
> ...



Yeah but it's activity! Unfortunately there's a confusion between activity and progress in many cases :lol: :lol: 

OK what testing are you doing here BC, because Kurt has an extremely valid point. 

Jon

Edit: I can think of any number of things that could be in those sludges.


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## bcgold (May 24, 2019)

anachronism said:


> I can think of any number of things that could be in those sludges.



Considering the source material and the acid used to harvest, care to give it your best shot.


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## bcgold (May 24, 2019)

kurtak said:


> bcgold said:
> 
> 
> > Never as expected.
> ...



The salts in the green liquid your referring to are chlorides, tested negative for values.



Harold_V said:


> Silver recovered with copper won't be pure, and your results reflect that fact.
> I had a policy of reserving the last removal of silver from my silver cell to be used in making the next batch of electrolyte. I operated my silver cell on a continual basis, until I'd parted all of the anodes I'd accumulated. There's method to my madness, which I'll explain.
> 
> If the silver used in making electrolyte yields anything more colorful than an almost colorless solution, especially after heating to a low boil, there's something present besides silver. By using the last silver recovered in the cell, I verified that I was depositing only silver, no copper, no palladium. My electrolyte, while still concentrated, after boiling, was just a hint of yellow, and became pretty much colorless when I added the required amount of distilled water. I always diluted the resulting solution, as allowed to cool, it grew immense silver nitrate crystals if not diluted.
> ...


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## glorycloud (May 24, 2019)

I still don't see an answer to the question:

*Why are you doing this?*

The last time I checked this is a "gold refining forum" and not
a lets make a pile of goo and see if we can filter it forum.

Not trying to be a donkey but this post is confusing and seems pointless.


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## markscomp (May 24, 2019)

looks like slime from Ghostbusters II -- just in a rotted form could be stuff from under a couch or bed from the movie Animal House circa 1978


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## anachronism (May 24, 2019)

bcgold said:


> anachronism said:
> 
> 
> > I can think of any number of things that could be in those sludges.
> ...



What "shot" would you like me to give you? You were looking for Tin recovery originally if my memory serves me correctly. Your HCl "process" is dissolving everything that's reacting to HCl. That's like using a sledgehammer to crack a nut, unless of course you've found a way to isolate the Tin from the rest. If you have then brilliant, because you're onto something. 

Without knowing what you've got it's a less valid proposition.

You need to be able to define exactly what you've got in order to be doing something that is worthwhile. Harold worked with jewellery rather than ewaste. Whilst he is extremely knowledgeable in his field, he's not the most relevant reference point here due to the whole smorgasbord of materials involved in dunking a PC board in HCl. 

That is what I am asking you, and I am more than happy to be proven to be overly pessimistic. I'm happy to learn so please enlighten me.

Jon


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## bcgold (May 24, 2019)

anachronism said:


> I can think of any number of things that could be in those sludges.



Considering the source material and the acid used to harvest, care to give it your best shot.

[/quote]


anachronism said:


> Your HCl "process" is dissolving everything that's reacting to HCl. That's like using a sledgehammer to crack a nut,
> Jon




It's what did not go into the HCL that is of interest, like perhaps a bit of gold from the wave solder which if there is any present will be in the slime's.

The acid treatment was not the most brilliant idea but it sufficed to see if there really is a bit of gold in that wave solder, in future a sand blast cabinet using a silica based media once spent could be added to a smelting operation.

If the tin proved to be a problem one could first remove the much more volatile tin beforehand.

Rain has shut this op down for the day, here is where I'm currently at with the slime's. I've now advanced to AR.


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## bcgold (May 24, 2019)

Some of the recovered tin.


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## anachronism (May 25, 2019)

I'll have to ask a relevant question. How do you know this is just Tin?


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## bcgold (May 25, 2019)

anachronism said:


> I'll have to ask a relevant question. How do you know this is just Tin?


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## bcgold (May 25, 2019)

This bowel contains the black slime's after incineration, if you look closely you'll see some a bit of carbon, during the ar leach this floated to the surface where it was easily skimmed off.

I once again incinerated this carbon then crushed it up and what I saw was the most beautiful red powder.


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## bcgold (May 25, 2019)

I have several pounds of activated carbon that I've harvested from fuel vapor canisters, if anyone knows how to clean this carbon from the hydrocarbons so that the AC maybe reused. Do share.


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## anachronism (May 25, 2019)

bcgold said:


> anachronism said:
> 
> 
> > I'll have to ask a relevant question. How do you know this is just Tin?
> ...



Huh? What relevance does that have to this question? Could you stop with the cryptic stuff please and just answer the question in plain english?

How do you know that what you have shown us is Tin, and tin alone? Howe have you tested and determined that it is Tin and not something else?


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## bcgold (May 25, 2019)

anachronism said:


> bcgold said:
> 
> 
> > anachronism said:
> ...



Credits for the Stannous image belong to laser_steve.

Have you read Hoke's Refining Precious Metals Wastes, a picture is worth a thousand words and the answer you seek is in Steve's stannous image. For further clarification will add this paragraph from Hoke's book.

In addition to making my stannous chloride test solution from this harvested tin have also evaporated some into stannous crystals.

Crystallizing is another way to purify an element.


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## anachronism (May 25, 2019)

You've got nothing here. 

You're wasting peoples' time.


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## FrugalRefiner (May 25, 2019)

bcgold, I can make stannous chloride from 60/40 lead tin solder and it will produce the same results. I can evaporate the solution and end up with crystals. That doesn't mean the solder is 100% tin. That's the point Jon is trying to make.

Dave


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## bcgold (May 25, 2019)

FrugalRefiner said:


> bcgold, I can make stannous chloride from 60/40 lead tin solder and it will produce the same results. I can evaporate the solution and end up with crystals. That doesn't mean the solder is 100% tin. That's the point Jon is trying to make.
> 
> Dave



Sulfuric acid would have turned the lead into a solid as a sulfide.

[youtube]https://youtu.be/OM8HzFHAEwA[/youtube]


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## bcgold (May 25, 2019)

Tin: its oxidation states and reactions with it 

https://melscience.com/US-en/articles/tin-its-oxidation-states-and-reactions-it/

The reaction between lead and hydrochloric acid
https://mammothmemory.net/chemistry...ction-between-lead-and-hydrochloric-acid.html


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## bcgold (May 25, 2019)

anachronism said:


> You've got nothing here.
> 
> You're wasting peoples' time.



Sorry you feel that way, this experiment is on my dime.


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## anachronism (May 25, 2019)

It may well be on your dime, but an experiment needs to be carried out from a position whereby you can quantify results. 

You can't, so it is all conjecture. What I find vexing is that you seem to have an aversion to straightforward answers, and that concerns me as inexperienced people will read your guesswork and think it has validity.

It could have validity but as I have mentioned already you have no hard data.


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## bcgold (May 25, 2019)

The brown powder along with a few other metals were all easily taken up in the aqua regia withing hours of applying heat what I'm now left with is a heavy layer of grey powder on the bottom of the vessel. It's like cement and the acids are having a difficult time making contact.

I guess its time to purchase a magnet stirring hot plate, in the meantime this project is on hold.

Some of the problems I've encountered on this journey, a few of the boards had a lead based solder, thankfully lead is slow to react with a dilute hydrochloric acid. But with the help of a bit of sulfuric acid added into the aqua regia this problem was resolved. I also use sulphamic acid to neutralize the nitric.

To precipitate the gold, I'm going to make a fresh batch of ferrous sulfate aka copperas, my preferred scrap iron is the laminates from transformers.

I thank the late Barran Realms for that tip, I had Frank on speed dial.

The platinum group from the small surface caps that would have been lost to dust had they been chiseled free from the boards.


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## bcgold (May 25, 2019)

anachronism said:


> It may well be on your dime, but an experiment needs to be carried out from a position whereby you can quantify results.
> 
> You can't, so it is all conjecture. What I find vexing is that you seem to have an aversion to straightforward answers, and that concerns me as inexperienced people will read your guesswork and think it has validity.
> 
> It could have validity but as I have mentioned already you have no hard data.



Your mistaken I have posted hard data with pictures and weights of the material recovered, if your after how much gold, silver or platinum group is present that information is not forthcoming.

Rather than rip me a new one try using google once in awhile my experiment is based on research not conjecture.

The circuit board itself, component leads and jumper wires all introduce copper into the solder in a wave soldering machine. ... Like the other coinage metals, gold and copper, silver will dissolve in the solder. Iron - Temperatures over 430°C will cause the solder to dissolve iron from the solder pot itself.


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## butcher (May 25, 2019)

what about all of the toxic waste generated?


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## bcgold (May 25, 2019)

butcher said:


> what about all of the toxic waste generated?



This is the main reason I suggested using a blast cabinet with silica media that could be incorporated into a smelting op.


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## anachronism (May 25, 2019)

bcgold said:


> anachronism said:
> 
> 
> > It may well be on your dime, but an experiment needs to be carried out from a position whereby you can quantify results.
> ...



Points in red above.


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## bcgold (May 26, 2019)

bcgold said:


> The circuit board itself, component leads and jumper wires all introduce copper into the solder in a wave soldering machine. ... Like the other coinage metals, gold and copper, silver will dissolve in the solder. Iron - Temperatures over 430°C will cause the solder to dissolve iron from the solder pot itself.





anachronism said:


> What's the relevance of this to the sludge?



Hot molten solder becomes an aggressive solvent a collector of metals including those considered precious, solder mask is applied to the board to keep contaminants at a minimum from entering the molten solder.but some gold plated areas remain exposed as well as a few other metals. 

It is these metals that you will find in the sludge,

Even at ambient temperature metals like tin and gold are never at rest, tin whiskers is the ruin of many electrical gadgets we use daily. Satellites in orbit have been rendered useless over whisker growth.

NASA,Tin Whisker (and Other Metal Whisker) Homepage
https://nepp.nasa.gov/whisker/

On circuit boards, ram and daughter cards the gold is plated over nickel to inhibit the gold from migrating to copper.

Without the sludge I have nothing as far as hard data all I have at the moment are the weights of the surface caps and harvested sludge, everything at this point is in solution no gold or platinum groups have been precipitated out at this time.

With the small number of boards used in this experiment, I'm rather impressed with the amount of sludge and surface caps I've been able to recover.

If this project produces positive results then investing in a blast cabinet would be prudent.


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## bcgold (May 26, 2019)

I've made a request to one of the global moderators to remove this thread.


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## anachronism (May 26, 2019)

OK, however the forum doesn't often work that way. It's a debate and there is information here.


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## galenrog (May 26, 2019)

Thread removal is unlikely to happen. There are lessons to be learned here. I will, however, leave it to forum moderators and administrators to comment on those lessons.

Time for more coffee.


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## FrugalRefiner (May 26, 2019)

As a couple of members have said, we don't usually delete threads just because they don't turn out as intended. I have read every thread in every section of this forum, and I have learned things in the most unlikely of places. There are things to be learned here as well.

Feel free to continue the thread. Don't be discouraged when others are critical, or call your assumptions into question. It's all a learning experience. I thought your original thread about using a graphite anode and electrowinning tin from the electrolyte was interesting. But when others ask questions, try to answer them and question your own assumptions rather than quoting previous posts from members that really don't answer their questions. We may all learn from your experiments.

Dave


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## anachronism (May 26, 2019)

Where Dave says your initial thread intrigued him, I can say that I completely agree with him. 

It was refreshing and different and it brought a smile to my face. I even commented to that effect. Where I diverge with BC is in that the initial appeal has gone because there currently appears to be no substance to this. 

Let me be frank, I dearly hope that there is substance because it would be a refreshing addition. 

So keep at it BC- but be prepared to be questioned. It's not personal, it's merely a search for knowledge that's backed up with data. 8) 8) 

Jon


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## bcgold (May 27, 2019)

[/quote]



anachronism said:


> What's the relevance of this to the sludge?



Thirty motherboards were processed, after precipitating the gold am now left with a palladium rich liquor which I'm going to cement with copper.

Since most of the magnetic s from the boards along with the gold plated pins located inside had been previously removed, I left the solder balls under chips removed and cpu pins located under the sockets.

So I'm thinking the majority of this gold came from the wave solder, anyhow that's my theory.

The gold recovered does not represent the true numbers as some is more than likely tired up with the tin.

The real value would be the palladium in those teeny surface caps that I have temporarily put on hold as it is proving a difficult process with out a stirring hot plate. The gray powder just lays on the bottom of the pot as cement as as immobile substance.

This capacitor powder is heavy enough you could probably pan it out just like some are doing with the gold bonding wires. Or use a Miller Table or even a sepratory funnel


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## anachronism (May 27, 2019)

Correct me if I am wrong however the boards you were processing appeared to be PC boards- is that right?

Let's see your Pd test. What did you use to get this result?


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## eastky2 (May 27, 2019)

bcgold said:


> I've made a request to one of the global moderators to remove this thread.



Why would you want this thread removed for? Just reading this thread is a GIANT LESSON for people that are newer to gold recovery and refining on things not to do. if I was a Mod here on the forum I would post a warning on the top of your thread telling new members to read as a educational lesson on what not to do.

There are great teachers on this forum. You are trying to reinvent the wheel and still running on flats.
if a long time member tells you it wont work take that advice lick your wounds and heed the advice that you were given. In a sense this stuff isn't rocket science if you take the advice given.


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## bcgold (May 27, 2019)

eastky2 said:


> bcgold said:
> 
> 
> > I've made a request to one of the global moderators to remove this thread.
> ...



Instead of blowing your own horn why not, set the record straight where necessary for newbies coming into this thread.

Then perhaps I might even learn something from your input.

The whole idea was to prove or disapprove if gold was present in wave solder in no way is this thread intended as a manor of processing boards.

As for the gold being present in the solder I'm satisfied with the results, but anyone with half a brain would soon realize there's not enough gold recovered to cover the cost of the acids used.


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## bcgold (May 27, 2019)

anachronism said:


> Correct me if I am wrong however the boards you were processing appeared to be PC boards- is that right?
> 
> Let's see your Pd test. What did you use to get this result?



You overlooked an important observation my friend ask yourself why is the gold floating on top of the liquor, why does it not sink to the bottom of the filter.

I'll tell you why, I should have precipitated the heavier platinum sister first, the liquor is super saturated.with the heavier elements. Which is causing the lighter gold to float, no harm done, in the meantime I'm cementing out the values with copper.

DMG will be soon on its way to me, funds are in Canadian dollar.


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## butcher (May 28, 2019)

Pulling the horse with the cart seems to be a hard method to test for minute traces of gold.


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## anachronism (May 28, 2019)

bcgold said:


> anachronism said:
> 
> 
> > Correct me if I am wrong however the boards you were processing appeared to be PC boards- is that right?
> ...



How about you answer the question I asked about the raw product. Also - "supersaturated with heavy elements?" I'm all ears because I've yet to see this phenomenon. 

Finally- you're guessing about the Pd then?


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## anachronism (May 28, 2019)

In the interests of the forum let me take what may appear to be a softer approach to this, because we need to get to a point where the facts are established. 

The solution you showed looks to me like a dirty AR solution, pregnant with gold and having the rubbish floating on the top that one would normally expect from a recovery AR process with mixed and dirty raw material. 

Your comments about it being super saturated with heavy metals are not something that is likely to happen from the product of 30 motherboards. Also if these are PC motherboards there is not going to be a load of Pd in there. Pd is only found in quantity on a particular range of boards, and PC boards are not one of them. I was basing my premise that these are PC boards based upon your photos of your electric cell and HCl leach. If that is incorrect then feel free to correct me. 

It doesn't help anyone to suggest Pd until you have properly tested for it, as colour means absolutely nothing in the case of so many base metals being dissolved. That is a given because everything interferes with everything else.

For a start if you would clarify the base material for all of us it would go a long way to providing some clarity, but I've given a few clues above. 

The reason that I appear to be taking such a hard line with this thread is that in the past we have had people make spurious claims with no data to back them up, and I want to be sure that this is not another one of those cases. Both for the good of everyone who will read this thread in the future, and for you so that you'll approach this from a more analytical perspective. We are all here to learn. I still do so every day. 

I hope that helps in some way. 

Jon


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## niks neims (May 28, 2019)

bcgold said:


> You overlooked an important observation my friend ask yourself why is the gold floating on top of the liquor, why does it not sink to the bottom of the filter.



I haven't been following this thread, but this comment offers too much entertainment potential...

That's an interesting equation, how much Pd (Sn, Ni) there must be dissolved in HCl solution, for resulting chlorides density to be higher than that of gold... Is that even physically possible?


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## Platdigger (May 28, 2019)

Looks like that could be copper floating.


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## niks neims (May 28, 2019)

Platdigger said:


> Looks like that could be copper floating.



at this point it could be anything, predominantly brown in color, that mostly floats on top  could it be Iron-Calcium-Litium?


seriously I doubt that it's even metallic... while we all know, sometimes fine gold precipitant floats on top due to surface tension, it usually looks different than seen in OP picture... to me it looks just like some dirt...


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## kurtak (May 28, 2019)

bcgold

First I want to say codos in your attempt to come up with a method to recover the gold from solder (here on the forum we already know solder contains gold - its been discussed MANY times here)


That said - your are going about it all wrong which is complicating the process

the cell you are running is a "parting cell" like a silver cell & like the "slimes" in a silver cell are "mostly" silver the slimes in your cell are "mostly" tin

You need to dissolve that tin (slimes) away with HCL & you need to treat the slimes "on there own" --- NOT mix them with the incinerated SMDs (caps)

mixing the slimes with other B.S. is doing nothing but complicating your process including but not limited to filtering problems

you are "over thinking" your process (in an attempt to come up with your own "better" process)

treat your slimes as one process (or better yet - just dissolve the tin in HCl) then treat the incinerated SMDs (caps) in another process

follow already tried - tested & "proven" processes

Tzoax & Patnor have already tried - tested & "proven" the process

:arrow: https://goldrefiningforum.com/phpBB3/viewtopic.php?f=33&t=22951&start=90#p267815 

dissolve your solder in HCl - filter out the solids - then treat with AR

Then you can recover your tin from the HCl by ether running a "winning" cell (instead of running it in a parting cell) --- or you can cement it from the HCL with zinc

Kurt


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## rickzeien (May 28, 2019)

Kurt, 

Thanks for posting that link. I had readybit before but did not comprehend it. 

Not sure I fully do now. Your post and a second read gave it some context of the challenge it was trying to solve. 



Sent from my SM-G950U using Tapatalk


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