# Precipitate tin from HCl



## GoldUser (Jun 15, 2022)

Hey,
I dissolved some tin solder in HCl, which were soldered to BGA chips. What is the best way to get tin chloride back to metallic precipitate? I'm just trying to recycle the HCl and learn a bit, so if the process costs more than new HCl I'm fine with it. If there is a better way to get the solder removed, I would also appreciate that.
David


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## Yggdrasil (Jun 15, 2022)

An electrolytic cell may do it.
There was a member trying it, but I don’t remember how it went.


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## olawlor (Jun 15, 2022)

According to the galvanic series scrap iron, aluminum, or zinc should cement out the tin if it hasn't oxidized too badly.

Distillation with sulfuric might let you pull HCl from the resulting ferric / aluminum / zinc chloride.

(Theory only, I haven't tried either--both tin and HCl are plentiful, so no reason to recover them.)


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## kurtak (Jun 16, 2022)

olawlor said:


> both tin and HCl are plentiful, *so no reason to recover them.)*


Per the bold print - current (spot) price of tin is $32.70 per kilo ($14.86 per pound)









Tin PRICE Today | Tin Spot Price Chart | Live Price of Tin per Ounce | Markets Insider


Tin Price: Get all information on the Price of Tin including News, Charts and Realtime Quotes.




markets.businessinsider.com





there is a market for it (spot *plus*) on Ebay









Tin Ingot products for sale | eBay


Get the best deals on Tin Ingot when you shop the largest online selection at eBay.com. Free shipping on many items | Browse your favorite brands | affordable prices.



www.ebay.com





Kurt


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## kurtak (Jun 16, 2022)

GoldUser said:


> I dissolved some tin solder in HCl,* which were soldered to BGA chips.*


Those solder balls likely have gold in them

There is gold plating "on the circuit board" where they solder the chip to the board

So - when they solder the chip to the board - the solder dissolves the gold plating & the gold alloys with the tin

The solder also has antimony in it 

so - when you dissolve the solder (tin) in HCl - it dissolves the tin - but not the gold & antimony

So the black powder in the bottom of the beaker - after dissolving the tin (solder) is a combination of antimony & gold

The solder from circuit boards can run about (plus/minus) 2 grams gold per pound of solder

You can cement the tin out of the HCl with zinc - but you don't recover the HCl

If you want to recover both the tin & the HCl you need to run it through a (electro) *winning* cell

Thats the sort story

Kurt


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## DHarr (Jun 16, 2022)

How are there so many people on this forum named David?

David


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## Yggdrasil (Jun 16, 2022)

Surely it has to do with the alignment of the stars and nothing with statistics.
And definitively not random at all.
Right….

Interesting observation though

And I forgot.. the colour of the last precipitate of course.

Regards, not David


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## orvi (Jun 16, 2022)

GoldUser said:


> Hey,
> I dissolved some tin solder in HCl, which were soldered to BGA chips. What is the best way to get tin chloride back to metallic precipitate?* I'm just trying to recycle the HCl *and learn a bit, so if the process costs more than new HCl I'm fine with it. If there is a better way to get the solder removed, I would also appreciate that.
> David


Recycling HCL from chlorides is not very plesant process, but it can be done, that is for sure. From three common "cementation" metals (aluminium, zinc and iron), choose aluminium or iron to do this, if you want to recover HCL from chlorides. Hydrated aluminium or iron chlorides decompose much more easily than ZnCl2. 
Altough I don´t know if precipitate of tin on either aluminium or iron would be well defined and filterable.

Note that you will also precipitate any lead that is present in the dissolved alloy. Maybe with careful addition of diluted H2SO4 into the mix, you would be able to part lead apart from tin, by creating insoluble PbSO4. Tin sulfate has much higher solubility in water than PbSO4. Need to be tested on small sample before moving to the whole lot.


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## Geo (Jun 16, 2022)

If you just want to remove the tin and not worried about recovering the tin, bubble air through it. Just as our stannous chloride test solution goes bad from absorbing oxygen from the air, the same will happen to just HCl. The tin will form tin oxide and settle to the bottom of the container. It may take a week but it does work.


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## Geo (Jun 17, 2022)

FYI, HCl does not condense like nitric acid does. It is formed by passing hydrogen chloride gas through a spray of water. The water is recirculated though a column that has spray nozzles spraying water. After the pH reaches 0, it is collected and bottled.


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## GoldUser (Jun 19, 2022)

olawlor said:


> According to the galvanic series scrap iron, aluminum, or zinc should cement out the tin if it hasn't oxidized too badly.
> 
> Distillation with sulfuric might let you pull HCl from the resulting ferric / aluminum / zinc chloride.
> 
> (Theory only, I haven't tried either--both tin and HCl are plentiful, so no reason to recover them.)


Would be a solution for me. Sadly I cant get my hands on sulfuric here.


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## GoldUser (Jun 19, 2022)

kurtak said:


> Those solder balls likely have gold in them
> 
> There is gold plating "on the circuit board" where they solder the chip to the board
> 
> ...


Thanks Kurt, 
could it be that there would be tin part of the settlement at the end? There is quite a bit of "dust" collected on the bottom of the beaker. I did not heat the HCl to dissolve I just let it sit for a few weeks now.
I havn't read much here about cold HCl dissolving tin.
Which metals are used as antimony in this case? 
Would there be some silver or/and copper which is mixed with the tin solder (except gold)?
Do metals in the case alloy together at all? 
David


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## GoldUser (Jun 19, 2022)

Geo said:


> If you just want to remove the tin and not worried about recovering the tin, bubble air through it. Just as our stannous chloride test solution goes bad from absorbing oxygen from the air, the same will happen to just HCl. The tin will form tin oxide and settle to the bottom of the container. It may take a week but it does work.


Thanks a lot,
thats the best solution I read beeing in my situation.


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## GoldUser (Jun 19, 2022)

orvi said:


> Recycling HCL from chlorides is not very plesant process, but it can be done, that is for sure. From three common "cementation" metals (aluminium, zinc and iron), choose aluminium or iron to do this, if you want to recover HCL from chlorides. Hydrated aluminium or iron chlorides decompose much more easily than ZnCl2.
> Altough I don´t know if precipitate of tin on either aluminium or iron would be well defined and filterable.
> 
> Note that you will also precipitate any lead that is present in the dissolved alloy. Maybe with careful addition of diluted H2SO4 into the mix, you would be able to part lead apart from tin, by creating insoluble PbSO4. Tin sulfate has much higher solubility in water than PbSO4. Need to be tested on small sample before moving to the whole lot.


I sadly cant get sulfuric. Is there another good solution on how to precipitate lead from an acidic chloride soltuion?


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## upcyclist (Jun 19, 2022)

kurtak said:


> Per the bold print - current (spot) price of tin is $32.70 per kilo ($14.86 per pound)
> 
> there is a market for it (spot *plus*) on Ebay
> 
> Kurt



Oh, I hear you. My friend that makes tin alloy faceting laps has not been enjoying the tin market the last few years. When I'm faceting, tin alloys are great.

When I'm refining gold and ready for some nitric, though, I just want it out of my face  Props to the OP for wanting to pull it back out.


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## dpgold (Jun 19, 2022)

GoldUser said:


> Hey,
> I dissolved some tin solder in HCl, which were soldered to BGA chips. What is the best way to get tin chloride back to metallic precipitate? I'm just trying to recycle the HCl and learn a bit, so if the process costs more than new HCl I'm fine with it.
> David


I've been dealing with this for a while trying to eliminate tin/lead from my stuff, sulphuric acid precipitates


GoldUser said:


> I sadly cant get sulfuric. Is there another good solution on how to precipitate lead from an acidic chloride soltuion?


I found some old car batteries which contains diluted sulphuric acid, I have filtered it and boiled in on low heat to evaporate the distilled water from it.


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## Geo (Jun 19, 2022)

Yes, acid/lead batteries use dilute sulfuric acid as the electrolyte if you can't source from anywhere else. You can buy fresh from auto parts stores here. It is the most expensive source that I can think of, but automobiles are in every country. It would be hard to regulate the electrolyte even if you have to collect it from old batteries.


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## orvi (Jun 19, 2022)

GoldUser said:


> I sadly cant get sulfuric. Is there another good solution on how to precipitate lead from an acidic chloride soltuion?


We often talk about sulfuric acid to precipitate lead sulfate, but eventually you can use any soluble sulfate to accomplish this  Plain sulfuric acid is just more convenient and practical, do not add any salts etc. But you can certainly easily purchase pH minus chemical for pools - which is usually NaHSO4 (sodium hydrogensulfate). This you can use to precipitate lead instead of sulfuric acid. Or any other soluble sulfate like sodium sulfate, potassium sulfate (sometimes accessible as fertilizer) or maybe also magnesium sulfate (Epsom salt for magnesium bath etc.).


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## dpgold (Jun 19, 2022)

orvi said:


> We often talk about sulfuric acid to precipitate lead sulfate, but eventually you can use any soluble sulfate to accomplish this  Plain sulfuric acid is just more convenient and practical, do not add any salts etc. But you can certainly easily purchase pH minus chemical for pools - which is usually NaHSO4 (sodium hydrogensulfate). This you can use to precipitate lead instead of sulfuric acid. Or any other soluble sulfate like sodium sulfate, potassium sulfate (sometimes accessible as fertilizer) or maybe also magnesium sulfate (Epsom salt for magnesium bath etc.).


from what type of solutions can I precipitate the lead, beside AR? AP, ....?


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## GoldUser (Jun 20, 2022)

orvi said:


> We often talk about sulfuric acid to precipitate lead sulfate, but eventually you can use any soluble sulfate to accomplish this  Plain sulfuric acid is just more convenient and practical, do not add any salts etc. But you can certainly easily purchase pH minus chemical for pools - which is usually NaHSO4 (sodium hydrogensulfate). This you can use to precipitate lead instead of sulfuric acid. Or any other soluble sulfate like sodium sulfate, potassium sulfate (sometimes accessible as fertilizer) or maybe also magnesium sulfate (Epsom salt for magnesium bath etc.).


Never really thought about that. Thanks


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## Geo (Jun 20, 2022)

Epsom salt (magnesium sulfate) is used in industry as a flocculent and clarifier.


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## dpgold (Jun 21, 2022)

magnesium from laptops frame, could be used to cement out metals below in the reactivities chart?


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## Martijn (Jun 21, 2022)

It will be an alloy, not pure Mg, So the most reactive metal will cement out everything below it. Even covering lesser reactive metals in the alloy. Or the alloy acts as a combined metal with its own reactivity. 
test and find out. Please do share the results here.


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## Martijn (Jun 21, 2022)

GoldUser said:


> I sadly cant get sulfuric. Is there another good solution on how to precipitate lead from an acidic chloride soltuion?


Lead Chloride is only slightly soluble in cold water. But first: is it actually lead? And not tin? 


dpgold said:


> I found some old car batteries which contains diluted sulphuric acid, I have filtered it and boiled in on low heat to evaporate the distilled water from it.


*Be very extremely carefull* "evaporating down" H2SO4!! It craves water and will only let it go at high temperatures!, meaning you'll have H2S04, much hotter than boiling water in a glass beaker or flask. 
Extremely dangerous and corrosive. 

Diluted works just as fine. No need to concentrate it for precipitation of Pb and risk your health.
stay safe. 

Martijn


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## dpgold (Jun 21, 2022)

Martijn said:


> It will be an alloy, not pure Mg, So the most reactive metal will cement out everything below it. Even covering lesser reactive metals in the alloy. Or the alloy acts as a combined metal with its own reactivity.
> test and find out. Please do share the results here.


What is the benefit of using some other metal higher in the series? It would not be better to cement out more valuable things from copper down? Is there something I am missing here in this cementing processes? I will share my results once I got a handle of it.


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## Geo (Jun 21, 2022)

dpgold said:


> What is the benefit of using some other metal higher in the series? It would not be better to cement out more valuable things from copper down? Is there something I am missing here in this cementing processes? I will share my results once I got a handle of it.


Copper will only cement less reactive metal. That will be any precious metal. Copper will not cement a more reactive metal. The more reactive the metal is, the more base metals it will cement. Keep in mind that there are metals that will not be removed from acidic solution through ionic exchange.


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## dpgold (Jun 21, 2022)

Geo said:


> Copper will only cement less reactive metal. That will be any precious metal. Copper will not cement a more reactive metal. The more reactive the metal is, the more base metals it will cement. Keep in mind that there are metals that will not be removed from acidic solution through ionic exchange.


Cementation is happening through ionic exchange?


Geo said:


> Copper will only cement less reactive metal. That will be any precious metal. Copper will not cement a more reactive metal. The more reactive the metal is, the more base metals it will cement. Keep in mind that there are metals that will not be removed from acidic solution through ionic exchange.


I mean , I have read so many things about cementation with zinc, iron, etc. but for PM recovery it would make sense first to cement out the PM with a metal which is lower in the reactivity series table and then cement out the rest again with something higher in the list to cement out the base metals. There might be more sides here to take into consideration which I don't get. AP usually is full of copper which went in solution but there could be others higher in the list like nickel, lead. 
Those base metals higher on the list would cement out the lower ones like copper (which would go back in solution and cement out others below)?


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## Geo (Jun 21, 2022)

dpgold said:


> Cementation is happening through ionic exchange?
> 
> I mean , I have read so many things about cementation with zinc, iron, etc. but for PM recovery it would make sense first to cement out the PM with a metal which is lower in the reactivity series table and then cement out the rest again with something higher in the list to cement out the base metals. There might be more sides here to take into consideration which I don't get. AP usually is full of copper which went in solution but there could be others higher in the list like nickel, lead.
> Those base metals higher on the list would cement out the lower ones like copper (which would go back in solution and cement out others below)?


Yes. Cementation is an ionic exchange process. You are replacing one ionized salt in solution with a more reactive salt. The salt being replaced in solution normally comes out as metal. The salt going into solution is you sacrificial metal. The first metal to use is copper. Copper is considered a Noble metal. Any metal that is found in nature in metallic form is a noble metal. The two elements that is responsible for all non-noble metals being found in nature in salt form is hydrogen and oxygen. In the hydrometallurgical process, there are two constants that is responsible for almost everything else. You are either adding or removing oxygen or you are either adding or removing hydrogen. Everything else is secondary to these two things. The electrical potential is next. That's the electromotive series of metals. The next thing you should study after getting a handle on all that is ORP. The ORP of a solution is what tells you what it's going to take to selectively cement what you want while keeping unwanted metals in solution or the other way around in selectively removing unwanted metals and keeping the target metal in solution. 
By the way, nickel does not cement from solution through ionic exchange.


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## tiggertree (Jun 22, 2022)

I hope it's OK to butt in here.
How do you preciptate or cement out nickel from a HCL solution?


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## dpgold (Jun 22, 2022)

Geo said:


> Yes. Cementation is an ionic exchange process. You are replacing one ionized salt in solution with a more reactive salt. The salt being replaced in solution normally comes out as metal. The salt going into solution is you sacrificial metal. The first metal to use is copper. Copper is considered a Noble metal. Any metal that is found in nature in metallic form is a noble metal. The two elements that is responsible for all non-noble metals being found in nature in salt form is hydrogen and oxygen. In the hydrometallurgical process, there are two constants that is responsible for almost everything else. You are either adding or removing oxygen or you are either adding or removing hydrogen. Everything else is secondary to these two things. The electrical potential is next. That's the electromotive series of metals. The next thing you should study after getting a handle on all that is ORP. The ORP of a solution is what tells you what it's going to take to selectively cement what you want while keeping unwanted metals in solution or the other way around in selectively removing unwanted metals and keeping the target metal in solution.
> By the way, nickel does not cement from solution through ionic exchange.


Nice, this is so cool, thank you.


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## dpgold (Jun 22, 2022)

Martijn said:


> It will be an alloy, not pure Mg, So the most reactive metal will cement out everything below it. Even covering lesser reactive metals in the alloy. Or the alloy acts as a combined metal with its own reactivity.
> test and find out. Please do share the results here.


I looked it up, it is the alloy az91d which contains many things like zinc, silicon,aluminum,iron,copper and other stuff however there should be Mg up to 90 percent. The most is aluminum at 9.7 percent. 

Aluminum, Al8.3-9.7Manganese, Mn0.15-0.50Zinc, Zn0.35-1Silicon, Si0.1Copper, Cu0.03Iron, Fe0.005Nickel, Ni0.002Others, each max0.02Magnesium, MgRemainder


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## dpgold (Jun 22, 2022)

tiggertree said:


> I hope it's OK to butt in here.
> How do you preciptate or cement out nickel from a HCL solution?


From what I have learned from the other members and still trying to learn, if you look up the reactivity series chart which arranges these elements in the order of their reactivity. I understood that once you put in solution a more reactive metal like cobalt which will go in solution and those metals below come out if they are present in solution. 
So to isolate nickel my understanding is that you should first cement out those metals below the metal you want and then after removing them cement out the one you want with a more reactive metal like cobalt, iron, etc (according to the chart). Also my understanding is that if you want to make sure there isn't other metal mixed with nickel you should use the one immediately above nickel on the chart (cobalt) unless you know for sure there is none. 
Or use iron if you know there is no cadmium and cobalt in the solution.


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## Martijn (Jun 22, 2022)

Although you seem to understand and explain it yourself in your last post, I feel like I'm repeating myself when it comes to displacement reactions or ion exchange. May I challenge all new members to thoroughly read this: 








When In Doubt, Cement It Out


When In Doubt, Cement It Out This is advice I often give to new members who find they've created a bit of a mess, and they're wondering how to recover their values (gold, silver, PGMs, etc.). Perhaps they've followed a process they've seen on YouTube that left out some important details...




goldrefiningforum.com




Together with this: 





Reactivity series - Wikipedia







en.wikipedia.org




And this: 








Dealing with Waste


I have been roaming this site for a few weeks, and with Hoke's book on it's way (fyi Harold) and Steve's DVD's I should be ready to start recovering pm's here pretty soon. I do have concerns about how to correctly deal with wastes. I am looking for some insight into how you guys deal with this...




goldrefiningforum.com





After reading this, let's discuss if you have any questions left. 

And last, before posting another question that can be easily found here by using the search button, read this:








Why Can't I Ask a Simple Question and get a Simple Answer?


Many new members are frustrated when they first join this forum. They may have experience on other internet forums where it is common for members to ask simple questions and get quick answers. They join this forum in hopes of getting similar responses to their questions about refining. These...




goldrefiningforum.com





After you died from a You tube copied chemistry experiment gone horribly wrong, your family's lawyer may find this forum and will look for a scapegoat to hold responsible for your mistake. 

That's why YOU must research and think for yourself, instead of asking for help and directions. 

Martijn.


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## Geo (Jun 22, 2022)

tiggertree said:


> I hope it's OK to butt in here.
> How do you preciptate or cement out nickel from a HCL solution?


Neutralize the acid. The nickel precipitates as a salt of what ever base you neutralize with.


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