Post by Anders Hoveland on Aug 1, 2011 0:54:10 GMT -8
www.youtube.com/watch?v=Bh-maHh0nvU
(NH4)2MnO4 explodes with a copious cloud of dark brownish-purple smoke.
The substance is sensitive to friction, and very easily is set off by flame.
It is not entirely chemically stable, and slowly degrades. It can be stored for about 4 months.
The permanganate ion is much more reactive oxidizer than perchlorate, which is why this salt is so sensitive and chemically unstable.
Like ammonium perchlorate, ammonium permanganate is another ammonium salt that is not very soluble (most ammonium salts are very soluble). Unfortunately, potassium permanganate is not very soluble either, so this is not advantageous for making it.
Preparation 1 (the below has not been tested)
Sodium permanganate can be made by dissolving a manganese compound, such as MnCl2 or MnO2 (but do not use potassium permanganate for this procedure), in bleach. The reaction turns purple. Add extra manganese compound to be sure that all the bleach has reacted. After thorough mixing for 30 minutes, a test is to add a little piece of manganese dioxide, which then should not dissolve, indicating all the hypochlorite in the bleach has been reacted.
Separately, mix a small quantity of ammonium sulfate (or ammonium nitrate or ammonium chloride), but only add a small quantity, with some ammonia. Too much ammonium sulfate will make the reaction acidic, which is bad since that will make the permanganate oxidize the ammonia. If you have a pH strip, the ammonia mixture with the ammonium sulfate should be preferably neutral, or slightly basic. Be sure all the ammonium sulfate is dissolved in the ammonia, some extra water might be added to help dissolve it.
Add the second mixture to the first, then lower the temperature to 10degC until purple crystals appear. Use a spoon to scoop out the crystals, then flter out the crystals using coffee filter paper, washing with with a little water. The crystals are ammonium permanganate. Note that no potassium compound can be used in the above preparation, since the potassium permanganate would then solidify out.
If there is trouble crystallizing out the ammonium permanganate, some ammonia (the concentrated type) can be added to the solution, which should help because of the "common ion effect". The solution should not be cooled too long, otherwise sodium sulfate (salt) will begin to solidify out with the ammonium permanganate. Actually, ammonium chloride or ammonium nitrate are better than ammonium sulfate to use in this procedure, because the sodium sulfate is less soluble than sodium chloride.
Preparation 2 (has been tested)
20 grams of potassium permanganate is dissolved into 200ml of boiling water, to this mix is added 250g of ammonium nitrate and allowed to dissolve. The solution is poured off into another beaker to leave any undissolved or decomposed products in the bottom. Chill the solution to 10°C to precipitate the NH4MnO4, the solution can be poured off to retrieve the reddish-purple crystals. Place the product onto absorbent paper and leave to dry at room temperature. Excess ammonium nitrate must be used, otherwise it is difficult to preferentially precipitate out only the ammonium permanganate, since it is not much less soluble than potassium permanganate.
For preparing solutions of permanganic acid:
2 MnSO4 + 5 PbO2 + 3 H2SO4 => 2 HMnO4 + 5 PbSO4 + 2 H2O
The reaction is slow. The lead sulfate solidifies out, then is removed. To the remaining solution, add baking soda to make more alkaline (otherwise HMnO4 is a reactive oxidizer), then add the ammonia. The sodium ions are not as problematic as potassium ions, since the sodium permanganate is much more soluble.
Aqueous solutions of permanganic acid partially decompose when heated to 40degC, and completely decompose if boiled. The solutions slowly degrade at room temperature, especially above 20degC. The decomposition products are hydrated MnO2 and oxygen gas. If the water is allowed to evaporate out, the oxygen that forms from decomposition contains traces of ozone, giving it a distinct odor. The solutions slowly oxidize elemental sulfur after a few days to dilute sulfuric acid.
Alternatively, ammonium sulfate to the barium permanganate would work, the barium sulfate would solidify out and could be separated out, but use plenty of water, since the ammonium permanganate is not very soluble either. the solution will then contain ammonium permanganate, and the water could be evaporated out in a warm dark place. After some evaporation, lowing temperature will help crystallize out product.
Unfortunately, potassium ferrate K2FeO4, oxidizes ammonia, so ammonium ferrate is not possible.
(NH4)2MnO4 explodes with a copious cloud of dark brownish-purple smoke.
The substance is sensitive to friction, and very easily is set off by flame.
It is not entirely chemically stable, and slowly degrades. It can be stored for about 4 months.
The permanganate ion is much more reactive oxidizer than perchlorate, which is why this salt is so sensitive and chemically unstable.
Like ammonium perchlorate, ammonium permanganate is another ammonium salt that is not very soluble (most ammonium salts are very soluble). Unfortunately, potassium permanganate is not very soluble either, so this is not advantageous for making it.
Preparation 1 (the below has not been tested)
Sodium permanganate can be made by dissolving a manganese compound, such as MnCl2 or MnO2 (but do not use potassium permanganate for this procedure), in bleach. The reaction turns purple. Add extra manganese compound to be sure that all the bleach has reacted. After thorough mixing for 30 minutes, a test is to add a little piece of manganese dioxide, which then should not dissolve, indicating all the hypochlorite in the bleach has been reacted.
Separately, mix a small quantity of ammonium sulfate (or ammonium nitrate or ammonium chloride), but only add a small quantity, with some ammonia. Too much ammonium sulfate will make the reaction acidic, which is bad since that will make the permanganate oxidize the ammonia. If you have a pH strip, the ammonia mixture with the ammonium sulfate should be preferably neutral, or slightly basic. Be sure all the ammonium sulfate is dissolved in the ammonia, some extra water might be added to help dissolve it.
Add the second mixture to the first, then lower the temperature to 10degC until purple crystals appear. Use a spoon to scoop out the crystals, then flter out the crystals using coffee filter paper, washing with with a little water. The crystals are ammonium permanganate. Note that no potassium compound can be used in the above preparation, since the potassium permanganate would then solidify out.
If there is trouble crystallizing out the ammonium permanganate, some ammonia (the concentrated type) can be added to the solution, which should help because of the "common ion effect". The solution should not be cooled too long, otherwise sodium sulfate (salt) will begin to solidify out with the ammonium permanganate. Actually, ammonium chloride or ammonium nitrate are better than ammonium sulfate to use in this procedure, because the sodium sulfate is less soluble than sodium chloride.
Preparation 2 (has been tested)
20 grams of potassium permanganate is dissolved into 200ml of boiling water, to this mix is added 250g of ammonium nitrate and allowed to dissolve. The solution is poured off into another beaker to leave any undissolved or decomposed products in the bottom. Chill the solution to 10°C to precipitate the NH4MnO4, the solution can be poured off to retrieve the reddish-purple crystals. Place the product onto absorbent paper and leave to dry at room temperature. Excess ammonium nitrate must be used, otherwise it is difficult to preferentially precipitate out only the ammonium permanganate, since it is not much less soluble than potassium permanganate.
For preparing solutions of permanganic acid:
2 MnSO4 + 5 PbO2 + 3 H2SO4 => 2 HMnO4 + 5 PbSO4 + 2 H2O
The reaction is slow. The lead sulfate solidifies out, then is removed. To the remaining solution, add baking soda to make more alkaline (otherwise HMnO4 is a reactive oxidizer), then add the ammonia. The sodium ions are not as problematic as potassium ions, since the sodium permanganate is much more soluble.
Aqueous solutions of permanganic acid partially decompose when heated to 40degC, and completely decompose if boiled. The solutions slowly degrade at room temperature, especially above 20degC. The decomposition products are hydrated MnO2 and oxygen gas. If the water is allowed to evaporate out, the oxygen that forms from decomposition contains traces of ozone, giving it a distinct odor. The solutions slowly oxidize elemental sulfur after a few days to dilute sulfuric acid.
Alternatively, ammonium sulfate to the barium permanganate would work, the barium sulfate would solidify out and could be separated out, but use plenty of water, since the ammonium permanganate is not very soluble either. the solution will then contain ammonium permanganate, and the water could be evaporated out in a warm dark place. After some evaporation, lowing temperature will help crystallize out product.
Unfortunately, potassium ferrate K2FeO4, oxidizes ammonia, so ammonium ferrate is not possible.