Sciencemadness Discussion Board

Oxidation of ammonia by KMnO4?

Samusan - 2-10-2019 at 01:15

Hello, does anyone know the reaction between ammonia and KMnO4?
[Edited on 2-10-2019 by Samusan]

[Edited on 2-10-2019 by Samusan]

teodor - 2-10-2019 at 11:31

Hi. The question is too broad. If you want to make HNO3 search for the methods which will work.

woelen - 2-10-2019 at 12:27

Ammonia and KMnO4 do not react at appreciable speed. Ammonia is not easily oxidized. You need hypochlorite, TCCA or chlorine to oxidize it.

teodor - 2-10-2019 at 13:39

In the original question (before it was edited) Samusan asked about oxidation to some oxide of nitrogen. And I believe that all methods mentioned by woelen can oxidise it maximum to nitrogen (but bleach gives probably NH2Cl/N2H4) . There is an information about decomposition of NH4MnO4 when some byproduct is NH4NO3 but I think the question was about some existing practical method.

[Edited on 2-10-2019 by teodor]

Samusan - 3-10-2019 at 08:57

Thank you everyone for your replies

Alkoholvergiftung - 3-10-2019 at 09:15

Kuhlmann wrote in one of his works that an dry mix of Potassiumchlorate and Ammoniumsulfate gives of NO2 when you heat it.Maybe an alternative for you.

[Edited on 3-10-2019 by Alkoholvergiftung]

woelen - 3-10-2019 at 23:13

The latter is a very dangerous thing to do. The mix of an ammonium salt and a chlorate may explode on heating! Don't do this!

Alkoholvergiftung - 4-10-2019 at 05:23

Ive looked again. Instead of KCLO3 , KNO3 should work too.
Source: "Justus Liebigs Annalen der Chemie" Band 63-64 seite 235.

[Edited on 4-10-2019 by Alkoholvergiftung]

VSEPR_VOID - 4-10-2019 at 11:23

Quote: Originally posted by woelen  
Ammonia and KMnO4 do not react at appreciable speed. Ammonia is not easily oxidized. You need hypochlorite, TCCA or chlorine to oxidize it.


I would be very careful with that. I want to say that some routes to hydrazine and hydrazine sulfate involve the oxidation of ammonia with hypochlorite. I may not be right but the reaction of TCCA and ammonia may yeild nitrogen trichloride, the explosive that cost Humphrey Davy his vision.

AJKOER - 17-10-2019 at 18:17

Look to a chemical radical attack of NH3 in the presence of an oxygen source. See, for example, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=83149...

One route is the electrochemical cell created with copper, oxygen (or better H2O2) and ammonia (and more so, with the addition of an NH4+ salt, serving as an electrolyte and a source of NH3 as NH4+ = H+ + NH3). General reference on the cell, see https://www.academia.edu/292096/Kinetics_and_Mechanism_of_Co...

In my opinion, the formation of e- in the cell with O2/H2O2 leads to the formation of the superoxide radical anion. This eventually leads to the reported formation of NH4NO2, which decomposes at less alkali pH to liberate much N2 gas. However, adding NaOH to maintain a high pH, is claimed to maintain the nitrite (I have not verified).

Caution: NH4NO2 is cited as very toxic, so take appropriate safety precautions.

[Edited on 18-10-2019 by AJKOER]

teodor - 1-11-2019 at 14:21

Quote: Originally posted by woelen  
The latter is a very dangerous thing to do. The mix of an ammonium salt and a chlorate may explode on heating! Don't do this!


How about gaseous ammonia and KClO3? Today I found this in "Inorganic chemistry", Fritz Ephraim:

"The oxidation of compound of tervalent nitrogen such as ammonia, nitrides or cyanides to nitrates or nitrites can take place at temperatures well below a red heat with the aid of oxygen of the air or of oxidising agents such as chlorate or sodium peroxide, providing water is excluded. A catalyst such as metallic silver or gold, or copper oxide or particularly nickel oxide, fascilitates the reaction. For instance, the reaction

3 KClO3 + 2NH3 = 2 KNO3 + KCl + Cl2 + 3H2O

takes place below 200 C, and urea, magnesium nitride or calcium cyananide can be "nitrified" with sodium peroxide."

There is the reference to " Hofmann, Ber., 1926, 59, 204"

I have no idea how explosive/exotermic the reaction between chlorate and ammonia can be but from this citation I expect the route should be more or less affordable.

AJKOER - 2-11-2019 at 05:37

Quote: Originally posted by teodor  
Quote: Originally posted by woelen  
The latter is a very dangerous thing to do. The mix of an ammonium salt and a chlorate may explode on heating! Don't do this!


How about gaseous ammonia and KClO3? Today I found this in "Inorganic chemistry", Fritz Ephraim:

"The oxidation of compound of tervalent nitrogen such as ammonia, nitrides or cyanides to nitrates or nitrites can take place at temperatures well below a red heat with the aid of oxygen of the air or of oxidising agents such as chlorate or sodium peroxide, providing water is excluded. A catalyst such as metallic silver or gold, or copper oxide or particularly nickel oxide, fascilitates the reaction. For instance, the reaction

3 KClO3 + 2NH3 = 2 KNO3 + KCl + Cl2 + 3H2O

takes place below 200 C, and urea, magnesium nitride or calcium cyananide can be "nitrified" with sodium peroxide."

There is the reference to " Hofmann, Ber., 1926, 59, 204"

I have no idea how explosive/exotermic the reaction between chlorate and ammonia can be but from this citation I expect the route should be more or less affordable.


OK, for most of us, I agree with Woelen!

Per your cited reaction, note that water is a product. As such, since water must be excluded per your source (likely to avoid any possible NH4ClO3 creation) in practice, basing the reaction on a chlorate instead of a peroxide, is, in my opinion, more likely an involved and potentially dangerous path.

Here is an interesting citation from Bretherick, Vol 1, Page 27 to quote:

"A pyrotechnic mixture of aluminium powder with potassium perchlorate, barium nitrate, potassium nitrate and water exploded after 24 h storage under water. Tests revealed the exothermic interaction of finely divided aluminium with nitrate and water to produce ammonia and aluminium hydroxide. Under the conditions prevailing in the stored mixture, the reaction would be expected to accelerate, finally involving the perchlorate as oxidant and causing ignition of the mixture."

So, normally a presumably safer perchlorate (not chlorate) mixture with, in situ created NH3 in the presence of water, may explode.

An interesting fact reported on Page 39 with respect to Aluminum chlorate is:

"During evaporation, its aqueous solution evolves chlorine dioxide, and eventually explodes."

So, Al3+ in the presence of aqueous acidic chlorate (and, I suspect, a role for air/oxygen and perhaps a transition metal impurity) on evaporation could be a source of explosive ClO2 gas, yet something else to be mindful about.

Also, depending on how the KClO3 was produced (for example, a photolysis path with nitrate at https://www.sciencedirect.com/science/article/abs/pii/S00092... ), there could be some KClO4 created as well. A particular dangerous compound is ethyl perchlorate. So, I suspect, one would want also to avoid creating any such mixtures with a further ethyl radical presence, as to quote from Page 318 on ethyl perchlorate:

"Reputedly the most explosive substance known, it is very sensitive to impact, friction and heat. It is readily formed from ethanol and perchloric acid."

[Edited on 2-11-2019 by AJKOER]

Alkoholvergiftung - 2-11-2019 at 06:16

H.Tamm wrote Potassiumpermanganate in excess boiled with ammonia solution forms Potasiumnitrate and MnO2.
Potassiumpermanganate oxidize some organic Nitrogen containing substances to potassiumnitrate (animal Gallert).

teodor - 31-3-2020 at 01:28

Quote: Originally posted by AJKOER  
Quote: Originally posted by teodor  
Quote: Originally posted by woelen  
The latter is a very dangerous thing to do. The mix of an ammonium salt and a chlorate may explode on heating! Don't do this!


How about gaseous ammonia and KClO3? Today I found this in "Inorganic chemistry", Fritz Ephraim:

"The oxidation of compound of tervalent nitrogen such as ammonia, nitrides or cyanides to nitrates or nitrites can take place at temperatures well below a red heat with the aid of oxygen of the air or of oxidising agents such as chlorate or sodium peroxide, providing water is excluded. A catalyst such as metallic silver or gold, or copper oxide or particularly nickel oxide, fascilitates the reaction. For instance, the reaction

3 KClO3 + 2NH3 = 2 KNO3 + KCl + Cl2 + 3H2O

takes place below 200 C, and urea, magnesium nitride or calcium cyananide can be "nitrified" with sodium peroxide."

There is the reference to " Hofmann, Ber., 1926, 59, 204"

I have no idea how explosive/exotermic the reaction between chlorate and ammonia can be but from this citation I expect the route should be more or less affordable.


OK, for most of us, I agree with Woelen!

Per your cited reaction, note that water is a product. As such, since water must be excluded per your source (likely to avoid any possible NH4ClO3 creation) in practice, basing the reaction on a chlorate instead of a peroxide, is, in my opinion, more likely an involved and potentially dangerous path.

[Edited on 2-11-2019 by AJKOER]


I didn't found much evidences about explosive properties of (NH4)2ClO3 in water solutions when the solution is fresh. You can check "Brauer, Hadnbook of Preparative Inorganic Chemistry", the Barium Chlorate preparation which uses this procedure: "A mixture of 122.6 g. of KC1O 3 , 70g. of (NH 4 ) 3 SO 4 and 350 ml. of hot water is evaporated in a porcelain dish with constant stirring.". Also I think when NH3 is in gaseous form and the reaction mixture has temperature > 100C there is no liquid water, and if we have conditions when (NH4)2ClO3 is decomposing instantly it should be not explosion because I don't see any change in phase state (like solid -> gas or liquid -> gas). But I am not specialist in energetic materials so I would like to read comments of somebody how have a first-hand experience with (NH4)2ClO3. As I said, what I found in a literature are contradictions.

I recall this thread because yesterday I did some experiment of reaction between Ca(ClO)2 (saturated solution) and (NH4)2S2O8 (as a powder) and I noticed not only Cl2 and NO2 smell but also some very pungent and strange odour I am not familiar with. So, I think it was exactly the case of NH3 oxidation mentioned by woelen. But I have no idea about all products, may be worth to make some qualitative analysis of the reaction products.


[Edited on 31-3-2020 by teodor]

[Edited on 31-3-2020 by teodor]

woelen - 31-3-2020 at 03:59

(NH4)2ClO3 ?? That's quite an exotic salt :P

I agree with you that NH4ClO3 in aqueous solution is not that explosive. My warning was against mixing dry ammonium salt and dry chlorate. That is asking for trouble.

I myself once made NH4ClO3 from aqueous solution (I have written a web page about that). This can be done quite safely, only when you get dry crystalline NH4ClO3 you must be really careful. The latter can decompose explosively violently.

Alkoholvergiftung - 31-3-2020 at 13:01

Destilling Potassiumdichromate with concentrated sulfuric Acid an Ammoniumsulfate gives nitric Acid too. Maybe it works with Potassiumpermanganate too.

Amos - 31-3-2020 at 15:48

Quote: Originally posted by Alkoholvergiftung  
Destilling Potassiumdichromate with concentrated sulfuric Acid an Ammoniumsulfate gives nitric Acid too. Maybe it works with Potassiumpermanganate too.


Yes, intensely heating a large quantity of a mixture that contains manganese heptoxide sounds just wonderful.

Alkoholvergiftung - 31-3-2020 at 23:30

It should Reakt imidatly with the Ammoniumsulfat. Its clear when you Dump it all in at once than you got Problems. And instead concentrated sulfuric Acid 80% or 50%.If it forms Permanganic Acid should be enough .Because i ve read you can oxidize Ammoniumsulfate with PbO2 or MnO2 in thin sulfuric Acid to nitric Acid throught Destillation.

[Edited on 1-4-2020 by Alkoholvergiftung]

teodor - 1-4-2020 at 02:12

Quote: Originally posted by woelen  
(NH4)2ClO3 ?? That's quite an exotic salt :P


Or, I am still recovering from bronhitis/coronovirus :)

I didn't find the page about NH4ClO3 on your site, woelen.

[Edited on 1-4-2020 by teodor]

chornedsnorkack - 1-4-2020 at 09:28

Quote: Originally posted by Amos  
Quote: Originally posted by Alkoholvergiftung  
Destilling Potassiumdichromate with concentrated sulfuric Acid an Ammoniumsulfate gives nitric Acid too. Maybe it works with Potassiumpermanganate too.


Yes, intensely heating a large quantity of a mixture that contains manganese heptoxide sounds just wonderful.


Safer than heating a smaller quantity of mixture that contains the same quantity of manganese heptoxide.
But even if your procedure is safe because the permanganate is dissolved/diluted in excess concentrated sulphuric acid, you still can have other side processes:
2Mn2O7->4MnO2+3O2, even though quietly;
Mn2O7+2NH4HSO4->2MnO2+N2+3H2O+2H2SO4

woelen - 1-4-2020 at 12:30

Quote: Originally posted by teodor  

I didn't find the page about NH4ClO3 on your site, woelen.

My fault, I remembered wrong, I made a web page about NH4BrO3 and NH4IO3: https://woelen.homescience.net/science/chem/exps/ammoniumhal...
I once did make NH4ClO3, but I never made a web page about that.

[Edited on 1-4-20 by woelen]

AJKOER - 3-4-2020 at 13:09

Per a source at https://www.softschools.com/formulas/chemistry/ammonium_chlo...

"It can violently explodes in concentrated solutions, when exposed to light or heat"

Here is a comment on NH4ClO3 per Wikipedia (https://en.wikipedia.org/wiki/Ammonium_chlorate), which may be helpful in providing clarity:

"Even solutions are known to be unstable. Because of the dangerous nature of this salt it should only be kept in solution when needed, and never be allowed to crystallize."

So, the nature of unwanted decomposition of ammonium chlorate occurring in concentrated solutions that have managed to crystallize, is likely due to the extreme friction sensitivity of the associated crystals.

A reference (see https://www.sciencedirect.com/science/article/abs/pii/S03043... ) states: "A knowledge of friction sensitivity is very important for determining manipulation safety for primary explosives." Apparently, NH4ClO3 scores very poorly, which is largely the reason that the salt has no uses commercially.

[Edited on 3-4-2020 by AJKOER]

teodor - 6-4-2020 at 01:27

Quote: Originally posted by AJKOER  

So, the nature of unwanted decomposition of ammonium chlorate occurring in concentrated solutions that have managed to crystallize, is likely due to the extreme friction sensitivity of the associated crystals.


This is an interesting hypothesis. Eventually I found this study: "Stability of ammonium halates in the solid state kinetic investigation of the thermal decomposition and ignition of ammonium chlorate" https://doi.org/10.1016/0010-2180(69)90004-2 .

They found that presence of ammonia inhibits decomposition/explosion when small amount of unreacted chloric acid leads to explosion.

I didn't read study of friction sensitivity yet but those works are referenced from that article.

Something to cite in connection to the topic:
"AC was found to bea very unstable compound.
The slow decomposition of a fresh preparation
commenced at 50 ° but did not go to completion;
about ten per cent of the AC remained undecomposed. The decomposition reaction is complex and can be characterized by the following
overall equation

8 NH4CIO3 = NH4NO3+ 2N2 + 3.5Cl2 + N2O + CIO2 + 2 O2 + 14 H2O

At higher temperatures, above 85°C, the decomposition of AC becomes explosive. The
reaction equation is then

2 NH4CIO3 = N2 + Cl2 + O2 + 4 H2O

The stability of the compound decrease significantly with ageing. This is understandable
if one recalls that, due to the low thermal
stability, storing the substances at room temperature or even at -5°C involves a relatively
high thermal pretreatment. According to microscope observations, small white spots apoear
on the surface of an AC crystal some days after
preparation, which indicates the start of the
slow surface reaction.

They also made hypothesis about a mechanism of decomposition which starts with breaking NH4ClO3 to NH3 and HClO3 and HClO3 reacts with HNO3 as a byproduct which speeds the reaction up. So, I don't see these conditions (like a chain reaction) in the reaction of KClO3 with gaseous ammonia.

[Edited on 6-4-2020 by teodor]

[Edited on 6-4-2020 by teodor]

[Edited on 6-4-2020 by teodor]

[Edited on 6-4-2020 by teodor]