Permanganate Synthesis

[Zeitgeist]

I Know there is already a thread but i'm not interested in using KClO3, if i could get KClO3 why bother??

Rather than reacting in a crucible, i wanted to do it in aqueous solution:

Form MnCl2 from MnO2 and HCl

(Hang on, i can't balance that yet, does Cl2 form? or OH- ?)

Oxidise with H2O2, and add a K or Na salt to get the product?

Will this work? I think it should.

Does $65 AU sound alright for 5L 50% Technical H2O2 or am i getting ripped off?

Thanks.

[Hang-Man]

let me check. No. it dosn't work. MnCl2 + H202 + K(NO3) = not purple = not K(MNO4)

[Zeitgeist]

I thought it could be done similar to this,

http://www.rhodium.ws/chemistry/potassium.dichromate.html

Could any similar technique work?

[blindreeper]

I think that is a damn fine price for 5L of 50% H2O2. Oxyplus is about $12 for 500ml (It is technical grade) and the 5L oxyplus for me is $90. So if you can get it for that price go for gold!

[me234]

What's the exchange rate for Us to AUssie dollars?

[xyz]

http://www.xe.com/ucc/ <-------- USE THIS FOR EXCHANGE RATES

$65 is about right for 5L of 50% H2O2, that's how much I paid for 5L of Oxyplus of the same concentration (50% H2O2).

[Zeitgeist]

Hang on, KMnO4 will oxidise H2O2, so this can't possibly work, can it. I need a stronger oxidant, right?

[nitric63]

KMnO4 is not capable of oxidizing H2O2 from what I understand. It is a
catalyst that causes H2O2 to decompose at a high rate though.

[blindreeper]

http://www.powerlabs.org/chemlabs/kmno.htm

There is a reaction with KMnO4 and high concentrated H2O2

"On the topic of potassium permanganate, it should also be mentioned that the reaction with hydrogen peroxide, particularly at high concentrations (50%+), is EXTREMELY violent and has been used to power turbopumps and rocket engines as the KMnO4 decomposes into O2 and Mn3O4, which then goes on to decompose the H2O2 into O2 and H2O, with the evolution of enough heat to turn the entire batch into a blast of steam."

I have done this on many occasions and when the H2O2 hits the KMnO4 a small pop/bang is heard and a plume of steam and O2 is shot out like an explosion.

[Zeitgeist]

Yeah, i've done that before too, but never with really concentrated H2O2....... That'll be something to try next week

Does anyone know how pure the MnO2 from batteries is, that'll probably be the starting point for this exercise. It'll be dissolved in HCl, seperating the graphite residue

Mn(2+) + 4H2O --> MnO4- + 8H(+) + 5e-

2e- + H2O2 --> 2OH-

I know H(+) is really H3O(+), but for simplicity......

Add the reactions, add the spectators and balance everything, and i came up with:

5H2O2 + 2MnCl2 + 2KOH --> 2KMnO4 + 4HCl + 4H2O

Sound good? I don't have any KOH atm, so i'll try for NaMnO4 when the H2O2 arrives

[blindreeper]

Won't work, well if it did the KMnO4 would react with the HCl to foom Cl2 from this reaction

16 HCl + 2 KMnO4 -> 5 Cl2 + 8 H2O + 2 KCl

Would it not just be easier to buy KMnO4?

[Zeitgeist]

If i can find KMnO4, i'll certainly just buy it

About how much does it cost you?

Mainly i just want to try the synthesis to see if it can be done

(There is a good place near here i just found specialising in Agricultural and pool chemicals, bulk commercial cleaning products etc. I'd say they can get most things, but i'm not game to ask about too many things at once. The next shot will probably be HNO3, i'll try other places for the KMnO4

The HCl isn't produced fast enough for that reaction to consume all the KMnO4, and excess hydroxide will easily take care of it, but could also be hard to seperate from the product.

[blindreeper]

I pay about $10 for 1kg. I think better than any synthesis you could do...

[0EZ0]

I don't see how you could produce KMnO4 in any usable quantity via a similar method derived from the dichromate synth on rhodium. Plenty of places sell high purity KMnO4 suitable for synthesis. To name a few try an animal supplies warehouse or an agricultural chemical/hardware store. The higher purity is usual found in products intended for use in veterinary practices.

If it's just for bragging rights then maybe a search on industrial processes for the manufacture of KMnO4 may provide some useful information. Spending about 30 mins searching and refining you should come up with a few gems.

Have you guys done your homework?

Technical grade (50%) H2O2 at anything over $10 AU a liter is pricey. Even at that price the seller gets more than a reasonable profit. Last I checked a 5 liter black poly container of food grade (better than tech supposedly) 50% Hydrogen Peroxide was about $30 AU. Most industrial places order it in massive poly drums and repackage with a huge mark-up in price. Oxyplus is one fine rip-off.