Sciencemadness Discussion Board

Preparation of SnCl2 dihydrate (Stannous Chloride)

Gigtator - 1-1-2019 at 13:40

Hello everybody,

after reading the forum for many years, I just decided to register, mostly because of a major drawback.

I recently bought some SnCl2 dihydrate from a shop that I specialized on coloring cotton. I got it really cheap and was planning to perform some reduction.
Long story short, reduction did not work. Melting point of the substance I bought was way too high to be SnCl2 dihydrate. I assume that the SnCl2 has mostly oxidized because of wrong storage conditions.

I know that SnCl2 is widely available by chemical suppliers for inflated prices. But buying things is not fun if you can make them on your own.

So does anybody of you know a way to make SnCl2 dihydrate. I am slightly discouraged by the idea of creating SnO by accident.
I would prefer to create SnCl2 dihydrate. But possibly I could also work with SnCl2 in in a Ph-Buffered solution. SnCl2 in HCl(aq) is not favorable since in reductions it may speed up unwanted hydrolysis.

Maybe somebody has an idea on how to create the SnCl2 dihydrate. Any help and advice would be appreciated.
By the way, I already used the search engine, but I could not find any technique for the preparation of SnCl2.

Thank you all in advance.
Gigtator

fusso - 1-1-2019 at 14:24

Not sure if this can satisfy you
https://www.youtube.com/watch?v=zziLOly2R8U

Gigtator - 1-1-2019 at 17:30

Quote: Originally posted by fusso  
Not sure if this can satisfy you
https://www.youtube.com/watch?v=zziLOly2R8U


Dear Fusso,

thank you for your comment. Unfortunately in the youtube video it is only shown, how to make an aqueous solution of SnCl2, which by the way contains HCl (aq).
I am looking for a way to make a SnCl2 or a SnCl2 solution, that does not contain HCl.

Maybe somebody knows how to make it.
Some sources pretend, that you can distill of the Water/HCl until the SnCl2 precipitates. Other sources pretend that the precipitate is SnO. Maybe somebody can clarify?


j_sum1 - 1-1-2019 at 17:46

Watch the video to the end, Gigtator. Nile explains the equilibrium between HCl and Zn2+ in solution and also says how dihydrate crystals can be obtained. It so[nds like it is difficult though. Are you sure that you can't use the acidified solution?

Tsjerk - 2-1-2019 at 09:09

As far as I know nitro-propenes are reduced by Sn(II) to the oxime which hydrolyses to the ketone with water. If you are aiming for the amine you should isolate the oxime and do the reduction in two steps.

Sn(II) is pretty acidic, meaning it forms insoluble hydroxides by pulling OH- from water when there is no acid like HCl around.

CobaltChloride - 2-1-2019 at 12:17

I was able to make this salt by a much more simple procedure.

After dissolving the tin in an excess of hydrochloric acid and filtering the solution to get rid of copper impurities in my tin, I placed the solution in a wide dish inside a sealable plastic box. I then placed a mix of sodium carbonate and anhydrous calcium chloride granules in this make shift dessicator. I opened it from time to time to check the state of the SnCl2 solution and release any pressure that might've build up.

After a few weeks, I was left with some nice colorless crystals in the SnCl2 dish. I added a bit of this substance to a FeCl3 solution and it immediately turned very light green, indicating that it did not oxidize for the most part.

[Edited on 2-1-2019 by CobaltChloride]

S.C. Wack - 2-1-2019 at 16:00

If stannite is so great, I have to wonder if their SnCl2 was shitty and better material doesn't work. Or maybe that's what's going on in (their) acetone/ethyl acetate/etc.

You like playing around with ketones but the ketone is unwanted. You want a P2P oxime but not the amphetamine. You want nitroalkenes and so on for the smell. Uh huh. Day old accounts that will never post in another thread are already impossible to believe.

The salt is crystallized as usual by cooling, with the usual addition for hydrolysis prone metal salts of enough acid to prevent/reverse oxygen attachment. Such salts are usually made from strong acid and more metal than will react with it.

j_sum1 - 2-1-2019 at 17:55

Well, that-s a bit extreme, Gigtator.
It is a valid question to ask what kind of chemistry you are doing. We are not really wanting to become a support service for drug cooks. If that is what you are about, then you are right: this is not the place for you.
OTOH, if you have a genuine interest in chemistry and want to contribute, don't be put off by a couple of little comments.

Sulaiman - 3-1-2019 at 04:52

I have two small batches of SnCl2 in HCl that I made as test reagent for gold in solution.
Reading this thread made me wonder why not just boil to dryness some of my solution to get the dihydrate ?

In a small test tube I heated c1ml of my tin chloride solution over a candle flame;
Initially the liquid boiled just like water does,
then I stopped to sprinkle some ammonia solution around to reduce the rusting of stuff in the shed,
and continued with the gentle boiling.
Initially water vapour could be seen above the test tube condensing as a mist,
soon the mist turned to white ammonium chloride smoke,
then bumping became more of a problem.
I stopped when the bumping became severe and my lab was full of 'smoke'
This is not the way to do it - more care is required :D

Just thought I'd mention it in case anyone tries similar

Felab - 8-1-2019 at 11:12

Quote: Originally posted by Sulaiman  
I have two small batches of SnCl2 in HCl that I made as test reagent for gold in solution.
Reading this thread made me wonder why not just boil to dryness some of my solution to get the dihydrate ?

In a small test tube I heated c1ml of my tin chloride solution over a candle flame;
Initially the liquid boiled just like water does,
then I stopped to sprinkle some ammonia solution around to reduce the rusting of stuff in the shed,
and continued with the gentle boiling.
Initially water vapour could be seen above the test tube condensing as a mist,
soon the mist turned to white ammonium chloride smoke,
then bumping became more of a problem.
I stopped when the bumping became severe and my lab was full of 'smoke'
This is not the way to do it - more care is required :D

Just thought I'd mention it in case anyone tries similar


The problem is that SnCl forms an equilibrium with HCl and if it gets neutral it will form Sn(OH)Cl. NileRed details it more in he's video

Tsjerk - 8-1-2019 at 12:01

Quote: Originally posted by CobaltChloride  
placed a mix of sodium carbonate and anhydrous calcium chloride granules in this make shift dessicator. I opened it from time to time to check the state of the SnCl2 solution and release any pressure that might've build up.
[Edited on 2-1-2019 by CobaltChloride]


I can imaging this works, as long as there is not too much carbonate, to make sure there is always a bit of a HCl atmosphere. As long as the water is taken off before the HCl, hydrolysis won't be too bad. I once used this stuff fresh from a commercial supplier and there were already quite some insolubles.

AJKOER - 20-1-2019 at 15:57

Some comments on SnCl2 and possible hydrates at http://tin.atomistry.com/stannous_chloride.html .

The above reference is an extract from old chemical journals on which the copyright has long since expired. It is repackaged and copyrighted by Atomistry.