sxl168
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Did I just accidentally make Sodium Manganate?
I was precipitating Zn +Mn carbonates from HCl + Alkaline batteries. I had just finished up the bulk precipitation and decanted off the liquid. I then
wanted to double check the liquid to make sure everything precipitated out, but upon adding more Sodium Bicarb. a very light tan precip. started
forming, which is usually MnCO3. So I wanted kick up the PH quite a bit but didn't have Sodium Carbonate nor Hydroxide on hand, so thinking that
Oxiclean is just Sodium Carbonate + H2O2, I mixed up a solution of Oxiclean and a added it to the decanted liquid. I was dumbfounded when the liquid
went from water clear to green/turquoise. Some brown precip. also formed which looked like hydrated MnO2.
I Tried to dig up info on Manganates, and saw the color of them is green. Upon further digging, I saw a little bit of info on Sodium Manganate, but
info found said it was pretty unstable in solution. There should be little to no potassium present as I only used Sodium Bicarb. and Oxiclean. I had
also stripped out the KOH from the batteries from previous dissolving runs. So right now I have this green unknown solution with a light tan layer on
the bottom, a small brown layer on top of the tan layer, and was hoping if anyone else thinks it's some sort of Manganate in solution. Maybe the
surfactant in Oxiclean is holding it in solution?
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Bot0nist
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What's in the oxiclean exactly? Have you seen its MSDS?
If you need sodium carbonate in a pinch it is trivial to make if you have sodium bicarbonate on hand.
"The sodium bicarbonate was then converted to sodium carbonate by heating it, releasing water and carbon dioxide:
2 NaHCO3 → Na2CO3 + H2O + CO2"
~ wikipedia
U.T.F.S.E. and learn the joys of autodidacticism!
Don't judge each day only by the harvest you reap, but also by the seeds you sow.
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sxl168
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Oxiclean is just Sodium Carbonate, Sodium Carbonate Peroxyhydrate (aka Sodium Percarbonate), and a surfactant (Ethoxylated Alcohol). I know about
"baking" the baking soda bit, but didn't get around to making it yet.
MSDS: http://www.ahprofessional.com/MSDS/
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Chemistry Alchemist
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Sorry to go a bit off topic but is there a way to get the hydrogen peroxide out? make a clean solution of more then 9% H2O2?
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blogfast25
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Quote: Originally posted by sxl168  | I was precipitating Zn +Mn carbonates from HCl + Alkaline batteries. I had just finished up the bulk precipitation and decanted off the liquid. I then
wanted to double check the liquid to make sure everything precipitated out, but upon adding more Sodium Bicarb. a very light tan precip. started
forming, which is usually MnCO3. So I wanted kick up the PH quite a bit but didn't have Sodium Carbonate nor Hydroxide on hand, so thinking that
Oxiclean is just Sodium Carbonate + H2O2, I mixed up a solution of Oxiclean and a added it to the decanted liquid. I was dumbfounded when the liquid
went from water clear to green/turquoise. Some brown precip. also formed which looked like hydrated MnO2.
I Tried to dig up info on Manganates, and saw the color of them is green. Upon further digging, I saw a little bit of info on Sodium Manganate, but
info found said it was pretty unstable in solution. There should be little to no potassium present as I only used Sodium Bicarb. and Oxiclean. I had
also stripped out the KOH from the batteries from previous dissolving runs. So right now I have this green unknown solution with a light tan layer on
the bottom, a small brown layer on top of the tan layer, and was hoping if anyone else thinks it's some sort of Manganate in solution. Maybe the
surfactant in Oxiclean is holding it in solution? |
Yes. Small amounts of manganate and permanganate. It's quite routine from MnO2 + strong oxidiser. It's happened to quite a few here, including me. I
used to use bleach (hypochlorite) to reoxidise Mn(OH)2 to MnO2 and often got a whiff of the purple MnO4(-).
But don't go and set up your permanganate business just yet  : as the sticky
permanganate thread shows, isolating K or NaMnO4 is extremely difficult at the hobbyist's level...
[Edited on 22-9-2011 by blogfast25]
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