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Non-Chemical What to use to remove tin from foils?

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Jmk88,
I can think of ways you could clean the foils without HCl, but I do not think that would help you much at this point, because it would only bring up a thousand more questions with very few answers.

If you are going to learn to recover and refine gold, you will need HCl, muriatic acid, hydrochloric acid, Clorhydric acid, or spirits of salt, common concrete etch or pool cleaner grade will do just fine.

Put up your acid and chemicals away, spend some time looking for muriatic or HCl while you are studying.

Study to gain an understanding before making a mess.

Before making another mess:
I would deal with the last two (study dealing with waste).
Save and dry any powders or solids store them in a safe place.
study the safety section gain an understanding of the dangers and how to do the chemistry safely.
set up a safe small lab.
Use Hoke's book to do the getting acquainted experiments.
Begin your study with a simple recovery process like using cupric chloride to recover gold from memory.
and then further your study of a simple refining process like using HCl and hypochlorite to refine the gold.
study everything you can find about it, before even thinking of opening a bottle of acid.
Study all of the problems that can and will be involved with a process before you open a bottle of acid.
Study all you can find about the acid and the metals before you open the bottle.

Study, and do the research of which mushrooms are good to eat before you make the toxic soup to eat.

Basically stop and study for now.

I would expect any further questions from you would be regarding the safety aspects and dealing with the toxic waste from these last two failed recovery attempts of making a mess before we even think about answering questions concerning how to get a few flakes of gold from some toxic trash.

Or you could just keep throwing mushrooms into a pot of acidic water solutions and see if they taste like soup and then maybe you can figure out which ones are poisonous, or ask the jedi why your tummy hurts.
 
AGold,

The section in Hokes book is pages 69-73.

I wouldn’t advise tasting the washings though.

Definitely need Jedi input after that.

Sulphuric acid is recommended after recovery. I use AP for recovery due to silly U.K. restrictions.

Can anyone suggest an alternative to Sulphuric? Caustic will remove lead nitrates but I don’t think the tin paste.

Can someone help!?

Thanks all.
 
Thanks Butcher.

I’ve been studying and studying.... and studying and studying.

I believe your assistance has allowed me to I’d the issue which is tin paste. Probably a common beginners mistake.

Where Hoke advises on Sulphuric, is there an alternative? I understand caustic will remove nitrates but not the paste.

Someone has advised me acetone (a jeweller) will completely remove tin paste. Is this correct and would there be any adverse affects?
 
Jmk88,
Can anyone suggest an alternative to Sulphuric? Caustic will remove lead nitrates but I don’t think the tin paste.


It is hard for us to keep up with what all your doing, and sometimes what you are talking about or working on, it might be easier if you kept all of your discussion in one topic or forum thread.

I do not know what you are talking about now, are you talking about removing lead nitrates powders from the gold foils?

lead nitrates are soluble, caustic can be used to make a more insoluble lead hydroxide, in a salt of sodium nitrate in solution, although you can lower the solubility of the lead in solution to about 10 milligrams per liter at around a pH of 10, adding more caustic and the amphoteric lead dissolves more into solution.

Pb(NO3)2 + NaOH --> Pb(OH)2 + NaNO3

HydroxidePPT.png

Sodium bisulfate is often used as an alternative to sulfuric acid, but then again I do not know what you're doing, and aparantly neither do you at this point.

Your statements or descriptions are also not easy to follow, one time you speak of working with 18K gold then we find out it is gold filled trash full of base metal, which could have been costume jewelry of pewter brass bronze and any other gold plated junk alloys for all we know...

And another time you speak of using the acid peroxide method (cupric chloride etch) to recover foils from junk jewelry and electronic trash, but you cannot find HCl in your country to wash the foils???

I am beginning to feel more lost and confused than you are on these questions.
 
Butcher,

I have 50 litres of 33% hcl. I have nitrates (sodium and potassium). I have 15% hypochlorite. I have sodium hydroxide.

It’s sulphuric and nitric we cant get. And above 11% peroxide.

I only work with rolled jewellery. Because of the profit margin.

I think, with the greatest respect, what I am asking is straight forward. And relative to this post.

What can you use to dissolve tin/solder paste. Hoke says sulphuric. As above, we can’t get this.

So what would we use as an alternative? That’s all I’m asking, and I believe that’s all the original post was asking.

I understand the lead will be fine. However, the solder paste is what is causing me, and the original poster an issue.

Hoke doesn’t touch upon sulphuric alternative so I was asking someone (yourself) who would know. Which you answered.

So my next question would be does bisulphate need any further process or can I/we simply replace the sulphuric with it?

Regards
 
Jmk88,
I think you have already got the questions answered, but I do not believe you understand the answers.

In another thread, You had gold foils with chloride salts
http://goldrefiningforum.com/phpBB3/viewtopic.php?f=49&t=28093&p=296348#p296348

In this thread, your concern is nitrate salts and metastannic acid.

niks neims said:
Agold2019 said:
Hi Lino thank you for the response. These are foils that came from pins and fingers and other gold plated copper nickel components from cell phone boards. There was also left a slimey grey residue which I think is tin. In my country it is hard if not impossible to get muriatic. I was wondering if lye could work? If not I will work on getting some muriatic and doing the test that way.

But it was no problem getting the nitric to make metastannic acid with? :) Oh the USA with it's elusive muriatic acid....By the way what is it's chemical formula?... you could try substituting it with hydrochloric acid...., it still won't work on metastannic without incineration, though...

also hit the books buddy, hard ;)

Some confusion may come from you not knowing what the different acids are called.
you have HCl but you cannot get muriatic acid...
 
Butcher,

I am not AGold! :D

I think you’re confusing the two of us.

I am fully aware that sulphuric will dissolve the tin paste. I understand that.

My question comes down to “can I substitute sulphuric for something?”

If I can with Sodium bisulphate (and yes I know the difference between sulphite) how do I do that? Do I mix with hcl and water?
 
Basically...

This is the answer. I think?

http://www.goldrefiningforum.com/phpBB3/viewtopic.php?t=25624
 
I am really confused now. why do want to use sulfuric acid to remove tin, what is the salt of tin a chloride or a nitrate?

What are you working on with what and how...
Please keep the questions in one thread so maybe we can follow...

Tin in HCl Tin will make a soluble stannous chloride, which can hydrolyze to stannic chloride.
This is not a problem unless gold was dissolved in solution with the stannous...


Tin and nitric will form a gelatinous metastannic acid.
If this metastannic acid paste was also mixed with gold foils, and we used HCl, we would also dissolve some of the gold locking gold up in solution as colloids.
We can incinerate the metastannic salts to form tin oxides that will dissolve in HCl without dissolving the gold.

Tin is one of the amphoteric metals it forms insoluble hydroxides that with more or an excess of alkalis will begin to dissolve again.

Sodium bisulfate could be used in a fusion process, as a substitute for sulfuric acid, but without knowing the details of what you are doing, which question, which member is asking, or which tin salt we are talking about, or why you need to use sulfuric acid, I cannot go further into this confusion...
 
Agold2019 said:
Where I live I may not be able to get HCL. Maybe I can,


Per the underlined --- I have a hard time believing you can't get HCl where you live - HCl is a "common" acid used all around the world - it is used (commonly) as a concrete cleaner as well as a cleaner for swimming pools as well as for Ph adjustment in swimming pools

So you should be able to find it in most hardware stores (usually in there paint department) &/or building supply stores &/or masonry supply stores &/or swimming pool supply stores

You NEED to find it because without it you can not/will not be able to "effectively" recover &/or refine the precious metals from circuit board --- HCL is an essential acid "required" for the recovery & refining of PMs from CBs

go find it - or - forget the idea of trying to recover/refine Pms from CBs --- try to do so without HCl will do nothing but cause you problems

Kurt
 
Jmk88 said:
Basically...

This is the answer. I think?

http://www.goldrefiningforum.com/phpBB3/viewtopic.php?t=25624

Jmk88

Yes - the thread you linked is "in part" the answer to the question

in my first reply in that thread - did you follow the link I provided there

if not - here it is - & it will provide you with the rest of the answer

:arrow: http://goldrefiningforum.com/phpBB3/viewtopic.php?f=37&t=15324&p=155859&hilit=tin+oxide#p155859

read the "whole" thread

in that thread you will notice my user name changed from kurt (in 2012) to kurtak (in 2015)

Kurt
 
You do not want or need to incinerate the tin chlorides especially if there is gold involved, the gold can go up in smoke in the fusion.

stannous chloride in solution will reduce gold and other metals or salts of metals in solution---itself being oxidized to a higher state converting the stannous to stannic chloride in solution.

Just a little about some of the more common tin salts.

SnCl2, tin (II) chloride, stannous chloride, solubility 84g/100ml H2O @ 0 deg C.

SnCl4, tin(IV) chloride, stannic chloride, Hydrolysis in water, pentahydrate very soluble.

SnSO4, Tin (II) sulfate, stannous sulfate, solubility 33g/100ml @ 25deg C, melting point 378 deg C (712 deg F).

SnO, tin (II) oxide, can be two different colors blue/black more stable than the red metastable, insoluble in water, amphoteric will dissolve in strong acid or base.

SnO2, tin (!V) oxide, stannic oxide, cassiterite ore, insoluble in water, amphoteric dissolves in strong acid or base, can be reduced to elemental tin in a reduction with carbon in the reverberatory furnace, stannic acid hydrate is also called stannic hydroxide.

Sn(OH)2, tin (II) hydroxide, stannous hydroxide, in air stannous hydroxide Sn(OH)2 is oxidized into stannic oxide SnO2.


H2SnO3, mettastannic acid, this is the tin that forms a gelatinous goo with nitric acid, amphoteric insoluble in alkalis but with excess can form mettastannate which is soluble in water but not soluble in the alkalis.

As far as using H2SO4 sulfuric acid to dissolve the tin oxides or tin chloride salts to form a soluble tin sulfate salt, I cannot see any reason you would want to do this, because the tin chloride is more soluble than the tin sulfates are...
lead chloride is not very soluble in cold water but much more soluble in hot water.
lead sulfates are insoluble.
 
butcher said:
You do not want or need to incinerate the tin chlorides especially if there is gold involved, the gold can go up in smoke in the fusion.

stannous chloride in solution will reduce gold and other metals or salts of metals in solution---itself being oxidized to a higher state converting the stannous to stannic chloride in solution.

Just a little about some of the more common tin salts.

SnCl2, tin (II) chloride, stannous chloride, solubility 84g/100ml H2O @ 0 deg C.

SnCl4, tin(IV) chloride, stannic chloride, Hydrolysis in water, pentahydrate very soluble.

SnSO4, Tin (II) sulfate, stannous sulfate, solubility 33g/100ml @ 25deg C, melting point 378 deg C (712 deg F).

SnO, tin (II) oxide, can be two different colors blue/black more stable than the red metastable, insoluble in water, amphoteric will dissolve in strong acid or base.

SnO2, tin (!V) oxide, stannic oxide, cassiterite ore, insoluble in water, amphoteric dissolves in strong acid or base, can be reduced to elemental tin in a reduction with carbon in the reverberatory furnace, stannic acid hydrate is also called stannic hydroxide.

Sn(OH)2, tin (II) hydroxide, stannous hydroxide, in air stannous hydroxide Sn(OH)2 is oxidized into stannic oxide SnO2.


H2SnO3, mettastannic acid, this is the tin that forms a gelatinous goo with nitric acid, amphoteric insoluble in alkalis but with excess can form mettastannate which is soluble in water but not soluble in the alkalis.

As far as using H2SO4 sulfuric acid to dissolve the tin oxides or tin chloride salts to form a soluble tin sulfate salt, I cannot see any reason you would want to do this, because the tin chloride is more soluble than the tin sulfates are...
lead chloride is not very soluble in cold water but much more soluble in hot water.
lead sulfates are insoluble.

So much to learn
 
kurtak said:
Agold2019 said:
Where I live I may not be able to get HCL. Maybe I can,


Per the underlined --- I have a hard time believing you can't get HCl where you live - HCl is a "common" acid used all around the world - it is used (commonly) as a concrete cleaner as well as a cleaner for swimming pools as well as for Ph adjustment in swimming pools

So you should be able to find it in most hardware stores (usually in there paint department) &/or building supply stores &/or masonry supply stores &/or swimming pool supply stores

You NEED to find it because without it you can not/will not be able to "effectively" recover &/or refine the precious metals from circuit board --- HCL is an essential acid "required" for the recovery & refining of PMs from CBs

go find it - or - forget the idea of trying to recover/refine Pms from CBs --- try to do so without HCl will do nothing but cause you problems

Kurt

Best believe it. It is controlled and you need a license.
 
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