July 18, 2019, 03:54:04 PM
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Topic: MnO2 Tricks  (Read 318 times)

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Offline AlphaScent

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MnO2 Tricks
« on: April 09, 2019, 09:05:15 AM »
Does anyone have any tricks for KMnO4 work up.  The MnO2 produced is pretty gross to filter.  Filter aid works relatively well, but are there any chemical methods to reduce or dissolve the MnO2.

The older literature treats the reaction with SO2, but that is pretty gross.  I have read in another post that sulfuric acid followed by H2O2 is a possibility.  Also, sulfuric and NaCl.  Does anyone have any experience with this?

Any tricks or ideas are greatly appreciated!


Cheers!
If you're not part of the solution, then you're part of the precipitate

Offline wildfyr

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Re: MnO2 Tricks
« Reply #1 on: April 09, 2019, 09:10:04 AM »
I don't but sulfuric and NaCl does sound the easiest and safest!

Offline AlphaScent

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Re: MnO2 Tricks
« Reply #2 on: April 09, 2019, 09:13:09 AM »
Using sulfuric and NaCl will produce Mn2+ and Cl2 gas.  Chlorine is kind of gross but I guess this is why god made hoods : )
If you're not part of the solution, then you're part of the precipitate

Offline wildfyr

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Re: MnO2 Tricks
« Reply #3 on: April 09, 2019, 10:37:27 AM »
I can't say I ever feel great about combining organics and H2O2 for explode-y reasons.

You can produce SO2/HCl by quenching thionyl chloride with water or alcohols and venting it through the reaction mixture. Urgh.

I stick by my first opinion.

Offline Babcock_Hall

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Re: MnO2 Tricks
« Reply #4 on: April 09, 2019, 10:57:35 AM »
Disclaimer:  I have never tried this with MnO2.  To remove something that is a fine precipitate, I might be tempted to use a Corex centrifuge tube at a moderate g-value.  Corex tubes are better than other glass centrifuge tubes but can still be broken by spinning too quickly.

Offline rolnor

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Re: MnO2 Tricks
« Reply #5 on: April 09, 2019, 11:57:53 AM »
I think you can use sodiumbisulfite and/or HCl(aq)

Offline AlphaScent

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Re: MnO2 Tricks
« Reply #6 on: April 11, 2019, 10:13:56 AM »
rolnor,

You are correct. 

So after not being lazy and doing some research I found out that the old literature treated with SO2 because MnO2 is readily reduced by SO2 to Manganese (II) Sulfate.  So I took some of the MnO2 and used a stoichiometric amount of sodium sulfite and treated with an equivalent of conc. sulfuric acid.  I did a slow addition on an ice bath.  It worked great!  The MnSO4 goes right into solution.  Easy Peazy.

Thank you all for the *delete me*

Cheers!
If you're not part of the solution, then you're part of the precipitate

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