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Bullion.Forum
Non-Chemical What to use to remove tin from foils?
- Thread starter Agold2019
- Start date
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Nope, I just spent some my time looking for information to try and answer to some of my questions, and I found more answers than I was looking for, which always leaves me looking for more, and provides me with more questions...
Lino,
I like it!
(similar to silver conversion)...
Lino,
I like it!
(similar to silver conversion)...
Lino1406 said:
Does that work with metastannic acid too?
Göran
I cannot see why it would not work.
Meta- stannic acid is structurally identical to SnO2 with more or less absorbed water.
B stannic acid (meta stannic acid) is formed with concentrated nitric acid and tin, In diluted nitric acid solutions, the tin will form stannous nitrate salts.
Meta stannic acid or B stannic acid the formula has been represented by several different formulas, such as H2SnO3, (H2Sn5O11 . H2O), or (SnO2 . H2O)5.
so with this we can write the reaction:
3Sn + 4HNO3 + XH20 --> 3(H2SnO3) + 4NO
or
3Sn + 4HNO3 + XH2O --> 3(SnO2 . H2O) + 4NO
B metastannic acid is insoluble in sulfuric acid even concentrated.
B meta stannic acid is very sparingly soluble in water
Meta- stannic acid is structurally identical to SnO2 with more or less absorbed water.
B stannic acid (meta stannic acid) is formed with concentrated nitric acid and tin, In diluted nitric acid solutions, the tin will form stannous nitrate salts.
Meta stannic acid or B stannic acid the formula has been represented by several different formulas, such as H2SnO3, (H2Sn5O11 . H2O), or (SnO2 . H2O)5.
so with this we can write the reaction:
3Sn + 4HNO3 + XH20 --> 3(H2SnO3) + 4NO
or
3Sn + 4HNO3 + XH2O --> 3(SnO2 . H2O) + 4NO
B metastannic acid is insoluble in sulfuric acid even concentrated.
B meta stannic acid is very sparingly soluble in water
A 4 hour boil in water removed almost every trace of the goo.
It was lead: not tin.
I added fresh boiled water every 45 minutes to keep approximately 800ml volume.
I’m not sure how much lead chloride I had as it was wet and hard to measure. Appreciate this isn’t answering the immediate questions on stannic, but I believe the original post should try the same.
I strongly, strongly, strongly advise reading Burchers posts “word for word” and especially his paper that’s downloadable.
It was lead: not tin.
I added fresh boiled water every 45 minutes to keep approximately 800ml volume.
I’m not sure how much lead chloride I had as it was wet and hard to measure. Appreciate this isn’t answering the immediate questions on stannic, but I believe the original post should try the same.
I strongly, strongly, strongly advise reading Burchers posts “word for word” and especially his paper that’s downloadable.
AGold,
I’m not sure what material you’re using but the key is to basically remove anything like this before you even go near hcl recovery.
Bit disappointed that no one has really explained how easy this is to do... as well as the importance. I believe Harold emphasises this, via incineration.
Having spent two days in London’s diamond district, Hatton Garden, I have been lucky to witness how the biggest U.K. refinery does this.
It’s extremely straight forward.
Bathe what you have in lye for 48 hours prior to starting any process. Within 60 seconds you’ll see the solder start to rise; as this is solder, it breaks the lead and the tin away. You do not need to worry about separation; simply pour off the solution. You will note any scrap gold as being oil free and as clean as you can chemically get.
Then you begin your recovery. You can use AP or nitric for this; your AP should be highly charged with copper to ensure no precipitation when steel goes into solution. Although still not an issue of this occurs as you’ll find copper is dissolvable is warm hcl or cold with a bubbler.
Nitric is obviously the best but very hard now days to obtain: even in the US.
Remember, the best joiner in the world is unlikely to match their skill with arbocultural knowledge. They don’t need to know how trees grow to apply their skill.
I think sometimes the chemistry and refinery processes are a bit convoluted in the sense that too much chemistry information is given.
That’s not saying you should ignore it; if anything you need to understand for safety.
If you obtain less than 37% hcl, the hazards are drastically reduced in the sense of vapour. It will still burn if you spill on skin but you will have enough time to water it and shouldn’t be an issue. Above 37% is not the case and is difficult to work with even with PPE. The fumes alone are not removed by hoods entirely. You should always be outside if using that or nitric in my opinion.
The answer to your question, simply put, is bathe in sodium hydroxide before doing anything.
I’m not sure what material you’re using but the key is to basically remove anything like this before you even go near hcl recovery.
Bit disappointed that no one has really explained how easy this is to do... as well as the importance. I believe Harold emphasises this, via incineration.
Having spent two days in London’s diamond district, Hatton Garden, I have been lucky to witness how the biggest U.K. refinery does this.
It’s extremely straight forward.
Bathe what you have in lye for 48 hours prior to starting any process. Within 60 seconds you’ll see the solder start to rise; as this is solder, it breaks the lead and the tin away. You do not need to worry about separation; simply pour off the solution. You will note any scrap gold as being oil free and as clean as you can chemically get.
Then you begin your recovery. You can use AP or nitric for this; your AP should be highly charged with copper to ensure no precipitation when steel goes into solution. Although still not an issue of this occurs as you’ll find copper is dissolvable is warm hcl or cold with a bubbler.
Nitric is obviously the best but very hard now days to obtain: even in the US.
Remember, the best joiner in the world is unlikely to match their skill with arbocultural knowledge. They don’t need to know how trees grow to apply their skill.
I think sometimes the chemistry and refinery processes are a bit convoluted in the sense that too much chemistry information is given.
That’s not saying you should ignore it; if anything you need to understand for safety.
If you obtain less than 37% hcl, the hazards are drastically reduced in the sense of vapour. It will still burn if you spill on skin but you will have enough time to water it and shouldn’t be an issue. Above 37% is not the case and is difficult to work with even with PPE. The fumes alone are not removed by hoods entirely. You should always be outside if using that or nitric in my opinion.
The answer to your question, simply put, is bathe in sodium hydroxide before doing anything.
Jmk88 said:
That advice cannot be given blindly. You mention in your post that people pay too much attention to the chemistry but if you did, you'd know why you can't say what you just said.
Fair?
It is all about chemistry or the movement of electrons.
You do not have to understand the chemistry, or about how electrons of atoms react with other atoms, as long as you understand what is going on with the metals, the acids, or the electrolytic reactions...
C.M. Hoke in her book shows the layman jeweler the chemistry involved in recovery or refining without going into any scientific detail or using the chemist lingo which she was surely well versed in, explaining the reactions without using chemical equations or explaining how the metals and acid react on an atomic level, so the laymen jeweler could recover and refine his gold.
You do not have to understand much about how a car engine runs to change a starter or to do a tune-up or to get one running with a mechanical problem. (Just google it, or search your youtube channels if all else fails).
But going beyond being the neighborhood shade tree mechanic, you would want to understand everything you could about how the engine runs and why down to the atomic level if necessary.
Understanding chemistry is going to another level of understanding that gives us more insight into the reactions and what could happen or what might have happened and helps us to get a better understanding of the mechanics.
You do not need to understand chemistry, geology, engineering or mineralogy as well as many other disciplines to be a prospector or miner, or to find gold, but to any good miner worth his salt would want to understand all of these disciplines and how gold reacts down to the atomic level...
You do not have to understand the chemistry, or about how electrons of atoms react with other atoms, as long as you understand what is going on with the metals, the acids, or the electrolytic reactions...
C.M. Hoke in her book shows the layman jeweler the chemistry involved in recovery or refining without going into any scientific detail or using the chemist lingo which she was surely well versed in, explaining the reactions without using chemical equations or explaining how the metals and acid react on an atomic level, so the laymen jeweler could recover and refine his gold.
You do not have to understand much about how a car engine runs to change a starter or to do a tune-up or to get one running with a mechanical problem. (Just google it, or search your youtube channels if all else fails).
But going beyond being the neighborhood shade tree mechanic, you would want to understand everything you could about how the engine runs and why down to the atomic level if necessary.
Understanding chemistry is going to another level of understanding that gives us more insight into the reactions and what could happen or what might have happened and helps us to get a better understanding of the mechanics.
You do not need to understand chemistry, geology, engineering or mineralogy as well as many other disciplines to be a prospector or miner, or to find gold, but to any good miner worth his salt would want to understand all of these disciplines and how gold reacts down to the atomic level...
Yes that’s what I was trying to say.
I think the chemistry side of things helps with safety too. I was rather enlightened this week and think it was the best 16 hours I could have given.
I was amazed at how easily solder is actually removed, yet how many people, myself included, fail to do so in their initial recovery stages.
The guy I was shadowing has a background in chemistry but says that once you understand the actual processes and have the safety in place, it’s a case of practicing over and over to become better and better. He kept stressing that trying to understand the chemistry beyond safety requirements initially will cause most people to go wrong through misunderstanding.
I think what he was trying to say is chemistry is for gifted minds where as anyone can pick up refining with safety and practice.
I think the chemistry side of things helps with safety too. I was rather enlightened this week and think it was the best 16 hours I could have given.
I was amazed at how easily solder is actually removed, yet how many people, myself included, fail to do so in their initial recovery stages.
The guy I was shadowing has a background in chemistry but says that once you understand the actual processes and have the safety in place, it’s a case of practicing over and over to become better and better. He kept stressing that trying to understand the chemistry beyond safety requirements initially will cause most people to go wrong through misunderstanding.
I think what he was trying to say is chemistry is for gifted minds where as anyone can pick up refining with safety and practice.
We can always start off learning to become a good shade tree mechanic and work on learning more in the field of work, improving our skill and gaining more of an understanding...
I do not think that to work to gain a better understanding of the chemistry around us is beyond anyone's mind or their abilities.
An understanding only improves our ability's, and thus our minds to be able to understand even more...
Heck, you can teach monkeys to recover and refine gold, but getting the monkeys to understand what is going on or when things do not go as planned maybe a bit harder, or when something about the chemical reaction is different... When the monkey sees and the monkey does, but the procedure or experiment does not go the way monkey was taught, or something was different...
I do not think that to work to gain a better understanding of the chemistry around us is beyond anyone's mind or their abilities.
An understanding only improves our ability's, and thus our minds to be able to understand even more...
Heck, you can teach monkeys to recover and refine gold, but getting the monkeys to understand what is going on or when things do not go as planned maybe a bit harder, or when something about the chemical reaction is different... When the monkey sees and the monkey does, but the procedure or experiment does not go the way monkey was taught, or something was different...
butcher said:
Well worded. Put another way - if you cannot understand why something happens how can you understand how to put something right when the recipe doesn't work?
Anyone could plant and grow some tomatoes, even if a few plants get lost along the way, but the farmer who has some understanding of the chemistry of his soil will be able to grow better tomatoes, and if he understands something about pest control may even have some for his table...
A good farmer also understands the importance of safety around the farm, the animals and the farming equipment and how dangerous his work can be, and how he can protect himself and his family...
A good farmer also understands the importance of safety around the farm, the animals and the farming equipment and how dangerous his work can be, and how he can protect himself and his family...
Hey, good day all.
I'm new to the forum and noticed this post of yours so I wanted to ask you a few questions, please?
I have successfully collected gold flake from fingers and recently attempted a recovery from CPU pins. That was challenging as I tried to soak in HCl first to remove the solder (as I thought I had to do prior to treatment with Nitric to remove the base metals) and noticed this issue - There was a precipitate (some tin compound?) that fell out WITH some gold and I had a lot of trouble trying to separate/filter them. Also, it appeared that something (the Tin compound?) was plating on the pins and the more HCl I added would just add more plating and fine gold particles that settled out. I eventually just treated it all with HNO3 and did end up with Au foils, but I'm sure I lost some yield in the process.
Any assistance would be appreciated.
Thx,
Buckly
I'm new to the forum and noticed this post of yours so I wanted to ask you a few questions, please?
I have successfully collected gold flake from fingers and recently attempted a recovery from CPU pins. That was challenging as I tried to soak in HCl first to remove the solder (as I thought I had to do prior to treatment with Nitric to remove the base metals) and noticed this issue - There was a precipitate (some tin compound?) that fell out WITH some gold and I had a lot of trouble trying to separate/filter them. Also, it appeared that something (the Tin compound?) was plating on the pins and the more HCl I added would just add more plating and fine gold particles that settled out. I eventually just treated it all with HNO3 and did end up with Au foils, but I'm sure I lost some yield in the process.
Any assistance would be appreciated.
Thx,
Buckly
attempted the recovery of gold from CPU pins.
I tried to soak in HCl first to remove the solder
(as I thought I had to do prior to treatment with Nitric to remove the base metals)
HCl will attack lead/tin solder.
https://en.wikipedia.org/wiki/Reactivity_series
Tin and lead are more reactive than hydrogen in the reactivity series of metals, as well as many other metals like nickel, iron which can also be attacked and can be alloys or plating onto the pins...
HCl alone will not attack metals below hydrogen in the reactivity series of metals, like copper, but if we have air or oxygen or some other oxidizing agent we can attack the copper or even gold metal.
noticed this issue -
There was a precipitate (some tin compound?) that fell out WITH some gold and I had a lot of trouble trying to separate/filter them.
Also, it appeared that something (the Tin compound?) was plating on the pins and the more HCl I added would just add more plating and fine gold particles that settled out.
Metal ions dissolved in a chloride solution can be displaced from the solution as the solution attacks a more reactive metal.
iron which is more reactive than copper, iron metal will give up electrons to copper ions in solution, displacing the copper from solution, or cementing or plating the copper out of solution as the copper gains electrons from the iron which now has lost an electron from its atom to become a chloride ion, in a displacement reaction the copper will tend to plate onto the iron as the electrons are exchanged and cement the copper from solution as a metal powder as the solution become saturated as an iron chloride.
one metal in a solution can be displaced by another more reactive metal...
The tin will dissolve into HCl as soluble stannous chloride SnCl2, which can hydrolyze into stannic chloride SnCl4.
Tin being so reactive it probably was not the metal you have seen plating out on the pins or which was being displaced from the chloride solution...
The lead will form a fairly insoluble PbCl2 salt...
I eventually just treated it all with HNO3 and did end up with Au foils, but I'm sure I lost some yield in the process.
Any time you have gold involved and you have previously used HCl, and are planning to move on to use HNO3 in a later step and do not wish to dissolve any gold, you need to remove any chloride salts through washing, heating to drive off chlorides, and incinerating the material to form metal oxides...
I tried to soak in HCl first to remove the solder
(as I thought I had to do prior to treatment with Nitric to remove the base metals)
HCl will attack lead/tin solder.
https://en.wikipedia.org/wiki/Reactivity_series
Tin and lead are more reactive than hydrogen in the reactivity series of metals, as well as many other metals like nickel, iron which can also be attacked and can be alloys or plating onto the pins...
HCl alone will not attack metals below hydrogen in the reactivity series of metals, like copper, but if we have air or oxygen or some other oxidizing agent we can attack the copper or even gold metal.
noticed this issue -
There was a precipitate (some tin compound?) that fell out WITH some gold and I had a lot of trouble trying to separate/filter them.
Also, it appeared that something (the Tin compound?) was plating on the pins and the more HCl I added would just add more plating and fine gold particles that settled out.
Metal ions dissolved in a chloride solution can be displaced from the solution as the solution attacks a more reactive metal.
iron which is more reactive than copper, iron metal will give up electrons to copper ions in solution, displacing the copper from solution, or cementing or plating the copper out of solution as the copper gains electrons from the iron which now has lost an electron from its atom to become a chloride ion, in a displacement reaction the copper will tend to plate onto the iron as the electrons are exchanged and cement the copper from solution as a metal powder as the solution become saturated as an iron chloride.
one metal in a solution can be displaced by another more reactive metal...
The tin will dissolve into HCl as soluble stannous chloride SnCl2, which can hydrolyze into stannic chloride SnCl4.
Tin being so reactive it probably was not the metal you have seen plating out on the pins or which was being displaced from the chloride solution...
The lead will form a fairly insoluble PbCl2 salt...
I eventually just treated it all with HNO3 and did end up with Au foils, but I'm sure I lost some yield in the process.
Any time you have gold involved and you have previously used HCl, and are planning to move on to use HNO3 in a later step and do not wish to dissolve any gold, you need to remove any chloride salts through washing, heating to drive off chlorides, and incinerating the material to form metal oxides...
good stuff man. learned alot from this. will be saving for future refrence
