I'm a beginning and I have a question regarding stannous chloride that's sat for a while and gotten the white hydroxide precipitate. Can this be regenerated by adding conc. HCl, or is it beyond saving? Is there any way to re-use the tin in there? Thanks!
What to do with old stannous chloride soln?
- Thread starter Alondro
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Quiklearner
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Throw it away and make a fresh batch. The tin should be able to be reused.
(assuming you mean the metallic tin shot used to keep SnCl2 "fresh")
(assuming you mean the metallic tin shot used to keep SnCl2 "fresh")
Easiest would be just to dispose it and make a new solution. You can prolong its life by tightening the container and making it airtight - oxygen will kill Sn(II) and convert it slowly to Sn(IV) - which is partly insoluble and unstable in aqueous conditions - forming precipitate of chloro/oxo/hydroxo tin(IV) compounds.
Always make the testing solution with HCl following the formula, ensuring metallic tin is present on the bottom of the solution. It should last for month at least. Undissolved metallic tin could be certainly put inside the fresh batch as it was suggested above.
Considering the ammount of testing solution needed and tin/solder cost, recycling or regenerating don´t make a lot of sense
And also, standard gold solution (just a tiny bit with concentration of say 0,5-1g/L gold is very handy - to test if stannous still work as expected. Personally, I will opt for that 0,5g/L solution - if your stannous is able to test this positive clearly, than it would certainly test positive stronger solutions
Thanks!Easiest would be just to dispose it and make a new solution. You can prolong its life by tightening the container and making it airtight - oxygen will kill Sn(II) and convert it slowly to Sn(IV) - which is partly insoluble and unstable in aqueous conditions - forming precipitate of chloro/oxo/hydroxo tin(IV) compounds.
Always make the testing solution with HCl following the formula, ensuring metallic tin is present on the bottom of the solution. It should last for month at least. Undissolved metallic tin could be certainly put inside the fresh batch as it was suggested above.
Considering the ammount of testing solution needed and tin/solder cost, recycling or regenerating don´t make a lot of sense
And also, standard gold solution (just a tiny bit with concentration of say 0,5-1g/L gold is very handy - to test if stannous still work as expected. Personally, I will opt for that 0,5g/L solution - if your stannous is able to test this positive clearly, than it would certainly test positive stronger solutions
