Make Potassium Permanganate

In this video, we explore the preparation of potassium permanganate, a valuable oxidant with a striking purple color. Starting with 43g of manganese dioxide, often obtained from greensand filter media, and 25g of potassium chlorate, the chemicals are thoroughly mixed. A can made of iron is chosen as the reaction vessel due to its resistance to the highly corrosive mixture.

All reagents are mixed long with 40mL of water and 60g of potassium hydroxide. The can is placed in a furnace and heated to 400 degrees Celsius for several hours. This step involves the oxidation of manganese dioxide to potassium manganate by potassium chlorate, with potassium hydroxide providing essential potassium ions and alkaline conditions.

Once cooled and soaked in water, the solid chunks of potassium manganate are retrieved. To convert potassium manganate into potassium permanganate, chlorine gas is used. A chlorine generator comprising 45g of trichloroisocyanuric acid in 100mL water and 75mL of 30% hydrochloric acid is employed to produce chlorine gas, which is then introduced into the potassium manganate flask. The reaction results in potassium permanganate with potassium chloride as a byproduct.

Once the reaction is complete, the mixture is vacuum-filtered and then chilled to separate potassium permanganate from potassium chloride and hypochlorite. The potassium permanganate crystals are beautiful black needles.

The final yield is approximately 30.7g or 39%, adjusted to 52% considering the purity of the manganese dioxide used. Both crystallizations of potassium permanganate are found to be 99% pure with a 1% margin of error, confirmed through titration.

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[NurdRage]

Note sure if i'll have another video next week, but i hope to have at least one more before the end of the month.

[daltonsoutherland]

Nurdrage is the O.G of chemistry youtube for me been watching his videos from the beginning and i hope he never stops making such beautiful content ❤️

[electricalychalanged]

You are right that the KMnO4 is stable over decades. I recently tested A big jar of it that was analytical grade but over 60 years old. It was still 99.5%.

[DangerousLab]

Nurdrage was the first Chem-tuber I watched since 2009, can't believe I am still watching it today, hope to see you again in the next 10 years!

[AlChemicalLife]

Going back through and binge watching nurdrage videos ! I've been watching since i was in 5th grade. Now i am 7 years out of highschool and work in a "lab" in the aerospace industry(machining and metallurgy). Dont think i would be where i am today without your inspiration!
Keep up the great work and thank you ! 😊

[jacobkudrowich]

You've helped ignite my passion for chemistry from a teenager unable to do any of these experiments to a young adult eager to experiment and learn especially by going back and finally trying all the old experiments i used to watch from your channel. Im sure you've done the same for thousands of others just like me.

[nikhill]

Those are some of the most beautiful crystals I have ever seen, I had personally never seen Pot. Permanganate crystals before, so to me this is astounding!
The method was absolutely killer too!

[wolpumba]

*Introduction and Context*
- 0:10: Video introduction.
- 0:12: The video focuses on making potassium permanganate.
- 0:16: Discusses applications, mainly as an oxidant and in redox titrations.
- 0:26: Buying vs. making potassium permanganate.
- 0:36: Making it is a "trophy achievement" for amateur chemists.
- 0:45: The primary goal is scientific exploration.

*Gathering Materials*
- 0:50: Weigh 43g of manganese dioxide.
- 0:58: Manganese dioxide quality and purity discussed.
- 1:11: Alternative sources of manganese dioxide.

*Preparing the Reaction Mix*
- 1:20: Mix with 25g potassium chlorate.
- 1:33: Use an iron can as a crucible.
- 1:45: Add 40mL water and 60g potassium hydroxide.

*Performing the Reaction*
- 2:00: Mix all reagents.
- 2:06: Heat the mixture in a furnace to 400°C.

*Chemical Process Explanation*
- 2:24: Chemistry behind potassium manganate formation.
- 2:57: Limitations on reaching potassium permanganate.

*After the Reaction*
- 3:31: Post-reaction procedures and complications.
- 3:43: Adding 300mL water for soaking.
- 4:03: Physical removal of solid potassium manganate.

*Further Oxidation*
- 4:20: How to further oxidize to potassium permanganate.
- 4:52: Using chlorine gas for oxidation.
- 5:54: Safer alternative using carbon dioxide.

*Purification and Yield*
- 6:40: Chilling the mixture.
- 6:55: Vacuum filtering and purifying.
- 7:25: Resulting solution of potassium permanganate.

*Crystallization and Final Yield*
- 7:29: Cooling and crystallization process.
- 7:37: Resulting crystals described.
- 8:17: Final yield figures and adjustments for purity.

*Testing Purity and Additional Notes*
- 8:37: Purity tested through titration.
- 9:02: Alternative recovery methods for higher yield.
- 10:03: Additional notes on reusing materials and long-term storage.

[LiborTinka]

Thank you for the walkthrough. I've found potassium permanganate syntheses in old textbooks (Biltz, Walton) that use the CO2 quenching or directly fusing MnO2 with K2CO3, then hydrolyzing the manganate - this 'fusion method' however leads to low yields due to partial decompostion to MnO2. Oxidation with chlorine is definitely more efficient.
One note about the crucible: Iron is normally inert to hydroxide, but can react at high temperatures (~500 oC), producing iron(III) oxide, sodium and hydrogen.

[Ismail-xqry]

You have no idea how long ive been waiting for a new video from my favorite youtuber and PhD chemist, thank you for this ❤ (P.S, are you going to make videos about transition metals like vanadium, and maybe some precious metals like palladium?)

Can't wait for the next video, Peace!

[Fellow_Traveller]

Why haven't I seen this channel in my subscription feed in years? I forgot it existed and suddenly it reappeared.

[NITETROUS]

You’re definitely one of the best to do it on YouTube . Appreciate your videos 100%

[UpLateGeek]

For some reason I read the title as "Potassium Pomegranate". The worse part is that it made total sense. Perhaps I shouldn't be watching chemistry videos after 2 am.

[Berghiker]

That was super helpful. Very well done. Finally someone can make potassium permanganate with great success! Fascinating experiment to explore the science of making it.

[SirLovestain]

We've been blessed with another NurdRage video.

[flomojou]

So great to see you back and doing science again regularly after the long break! Love your content, looking forward to your next video.

[gnarkill]

The most trusted most deepest voice in science!

[kaezaklimber]

Now we only need to bring back Chemplayer, Rhodanide, Doug's... the old gods of chemistry

[wsmith]

Potassium permanganate is used as a medication for a number of skin conditions. This includes fungal infections of the foot, impetigo, pemphigus, superficial wounds, dermatitis, and tropical ulcers. For tropical ulcers it is used together with procaine benzylpenicillin.

[lufax]

Being a follower on Twitter, I was waiting for this video to drop!