Sciencemadness Discussion Board

Most potent H2O2 decomposition catalysts available to an amateur

John paul III - 15-7-2020 at 08:00

Some months ago I was playing with 60% H202 and unknowingly I used a silver spoon to transfer the liquid from a container, and the peroxide immediately started bubbling (it did look and sound like violent boiling) around the spoon. Are there solids or thick liquids available to an amateur that are even more potent in catalysing the decomposition of H2O2?

[Edited on 15-7-2020 by John paul III]

Whathappensif - 15-7-2020 at 09:17

Most transition metals, including KMnO4. Even yeast works.

Bedlasky - 15-7-2020 at 09:51

Many metal oxides or hydroxides (MnO2, FeO(OH), CuO, Cu(OH)2, CoO(OH), NiO(OH) etc.)

Aqueous Fe3+ solutions

Alkaline molybdate solutions


There are more transition-metal based catalysts, but I have personal experience with these.

[Edited on 15-7-2020 by Bedlasky]

Fulmen - 15-7-2020 at 11:11

Did you even consider Wikipedia? It lists several catalysts, including potassium iodide which is supposed to be quite effective.

John paul III - 15-7-2020 at 11:29

ok, I just did a quick experiment and ordinary steel yielded a good result

draculic acid69 - 15-7-2020 at 16:59

Quote: Originally posted by Fulmen  
Did you even consider Wikipedia? It lists several catalysts, including potassium iodide which is supposed to be quite effective.

I want to try rubidium iodide. Sodium iodide works but poorly compared to potassium iodide so following the order of reactivity means it should be even better than

woelen - 15-7-2020 at 23:03

I don't think that the metal ion makes a great difference, it is the iodide which does the trick. Probably, NaI is less soluble in concentrated hydrogen peroxide solutions and that makes it act slower. If you want a good comparison, then you should mix solutions of NaI and KI of equal molarity with equal volumes of hydrogen peroxide of the same concentration and.

The most violent decomposition reactions I observed with KMnO4 or freshly prepared hydrous MnO2 or Mn2O3. If you drip 60% H2O2 on one of these reagents, then I expect a little cloud of hissing steam on addition of each droplet.

unionised - 16-7-2020 at 02:46


Well, OK, the catalase enzyme present in blood.
On a mole for mole basis it's probably the best catalyst for peroxide decomposition that you will find.

"catalase has one of the highest turnover numbers of all enzymes; one catalase molecule can convert millions of hydrogen peroxide molecules to water and oxygen each second"

The reaction with permanganate is not catalytic, but stoichiometric.

woelen - 16-7-2020 at 04:25

Quote: Originally posted by unionised  
The reaction with permanganate is not catalytic, but stoichiometric.
I fully agree, but the resulting very finely divided MnO2 does a hell of a job in decomposing the remaining H2O2.

I once did an experiment with 10 ml of 30% H2O2 in a small narrow necked bottle (50 ml), to which I added a single small crystal (appr. 1 mm size) of KMnO4. This resulted in an amazing plume of decomposing H2O2 and steam! It must be really impressive if this experiment is performed with 60% H2O2. I, however, only had 30% H2O2 (and at the moment I only have low-concentration H2O2, since 2016 we cannot buy more concentrated than 12%).

[Edited on 16-7-20 by woelen]

Fery - 16-7-2020 at 06:17

unionised - blood was my first idea too (as I often saw 3% medicinal H2O2 for cleaning wounds, bubbling also caries out any dirt out of wound), the first idea was soon followed by MnO2...
concentrated H2O2 would very likely destroy any enzyme very quickly... for diluted H2O2 it would be ultimate but I do not think for concentrated H2O2
decomp of H2O2 is exothermic so enough concentrated H2O2 (I approximate 10% and more) decomposes faster and faster as it is started in cold but soon the reaction heats itself which further speeds up the reaction rate
I have one good message for everyone keen to try the enzymatic route - no need to hurt yourself to obtain the blood enzyme, you could use horseradish peroxidase instead :)
woelen - here you can still buy 30% H2O2 legally, it just requires ID card

[Edited on 16-7-2020 by Fery]