bluamine
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Sodium peroxide from Sodium bicarbonate??
I read that I can produce sodium peroxide by heating sodium bicarbonate until it becomes yellow (like peroxide)... but
I continued heating it for half an hour, & it did not become yellow..
My question is: what temperature should I realize??!!
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ave369
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Will. Not. Work.
Smells like ammonia....
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deltaH
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Might work by heating 'sodium percarbonate' (sodium carbonate perhydrate), maybe that's what he thought he read. Hydrogen peroxide is a weak acid, so
with heating I can see how this might decompose to NaO2 with liberation of CO2 and water.
Or perhaps heating sodium bicarbonate and conc. H2O2 might also work, but it would probably need to be very conditions specific. I suggest you track
down the original reference you read.
Hydrogen peroxide used to be made by the hydrolysis of sodium peroxide, but in the presence of large amounts of excess sodium hydroxide which is
extremely soluble, you might be able to precipitate small amounts the peroxide hypothetically (common ion effect) by combining sodium hydroxide and
conc. hydrogen peroxide. Cooling would be advisable as well, obviously.
I've added sodium hydroxide prills to a tiny amount of 50% peroxide and that does go yellow, but yields are probably poor the way I did it. Still,
maybe if you chill the H2O2 really cold and actually work out the optimal amount of sodium hydroxide to add (ideally you want to end up with a
saturated sodium hydroxide water solution after addition and reaction), it might work better.
[Edited on 9-10-2015 by deltaH]
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bluamine
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Quote: Originally posted by deltaH  |
Might work by heating 'sodium percarbonate' (sodium carbonate perhydrate), maybe that's what he thought he read. Hydrogen peroxide is a weak acid, so
with heating I can see how this might decompose to NaO2 with liberation of CO2 and water.
Or perhaps heating sodium bicarbonate and conc. H2O2 might also work, but it would probably need to be very conditions specific. I suggest you track
down the original reference you read.
Hydrogen peroxide used to be made by the hydrolysis of sodium peroxide, but in the presence of large amounts of excess sodium hydroxide which is
extremely soluble, you might be able to precipitate small amounts the peroxide hypothetically (common ion effect) by combining sodium hydroxide and
conc. hydrogen peroxide. Cooling would be advisable as well, obviously.
I've added sodium hydroxide prills to a tiny amount of 50% peroxide and that does go yellow, but yields are probably poor the way I did it. Still,
maybe if you chill the H2O2 really cold and actually work out the optimal amount of sodium hydroxide to add (ideally you want to end up with a
saturated sodium hydroxide water solution after addition and reaction), it might work better.
[Edited on 9-10-2015 by deltaH] |
My purpose is to make concentrated hydrogen peroxide (I got only 3% concentrated & that's very poor).. So I think I have to electrolyse NaOH to
get some sodium metal then mix it with NaOH to get sodium oxide, which can be heated to get peroxide. I think this will work by adding this last to
water:
Na2O2+H2O=NaOH+H2O2
I want you guys give me your advices
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Pyro
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concentrating 3%H2O2 is muuuch easier than makinh Na from NaOH just to turn it into the oxide!
all above information is intellectual property of Pyro.  |
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unionised
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| Quote: Originally posted by deltaH |
Might work by heating 'sodium percarbonate' (sodium carbonate perhydrate), maybe that's what he thought he read. Hydrogen peroxide is a weak acid, so
with heating I can see how this might decompose to NaO2 with liberation of CO2 and water.
Or perhaps heating sodium bicarbonate and conc. H2O2 might also work, but it would probably need to be very conditions specific. I suggest you track
down the original reference you read.
Hydrogen peroxide used to be made by the hydrolysis of sodium peroxide, but in the presence of large amounts of excess sodium hydroxide which is
extremely soluble, you might be able to precipitate small amounts the peroxide hypothetically (common ion effect) by combining sodium hydroxide and
conc. hydrogen peroxide. Cooling would be advisable as well, obviously.
I've added sodium hydroxide prills to a tiny amount of 50% peroxide and that does go yellow, but yields are probably poor the way I did it. Still,
maybe if you chill the H2O2 really cold and actually work out the optimal amount of sodium hydroxide to add (ideally you want to end up with a
saturated sodium hydroxide water solution after addition and reaction), it might work better.
[Edited on 9-10-2015 by deltaH] |
Still.
Will. Not. Work.
Not least, because sodium peroxide is used to generate oxygen by the reaction with CO2 and water.
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deltaH
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Ah, then no basis in fact, just thought he might have misremembered the name.
NaOH prills added to conc. H2O2 does turn pretty yellow though... there might be something in there with optimisation. Anyway, pointless since opp's
after H2O2.
Pyro's right, much easier to concentrate the dilute H2O2.
Welcome back Pyro, long time no see, at least for me 
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bluamine
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[/rquote]
Still.
Will. Not. Work.
Not least, because sodium peroxide is used to generate oxygen by the reaction with CO2 and water.[/rquote]
So what can I do?? do you think I can use a concentrated acid such as sulphuric?
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Detonationology
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| Quote: |
My purpose is to make concentrated hydrogen peroxide (I got only 3% concentrated & that's very poor)
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What is your goal concentration? Freezing 3% hydrogen peroxide yields a small concentration of ~30% H2O2.
“There are no differences but differences of degree between different degrees of difference and no difference.” ― William James
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ave369
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If you want hydrogen peroxide, buy a Buchner flask and any form of vacuum pump. Pour the dilute hydroxide from the drugstore into the flask, suck
enough vacuum, and heat on a bain marie. Water will boil from the solution, and hydrogen peroxide will remain.
Smells like ammonia....
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m1tanker78
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I've always prepared sodium peroxide by burning sodium metal in a gentle stream of dry O2. Hydrolyzing to hydrogen peroxide works but can be quite
tricky. The water and container must be absolutely clean and chilled to just above freezing. The reaction produces sodium hydroxide and liberates
quite a lot of localized heat -- two formidable enemies of hydrogen peroxide. Even with stabilizer(s) added, the hydrogen peroxide tends to decompose
fairly rapidly. Forget about storing it for more than a few hours, tops. Vigorous stirring is a must and you have to add the sodium peroxide a little
at a time. You must also protect it from air moisture else you'll have a puddle of mush. Burning sodium in air works but it must be DRY air.
Freezing drugstore peroxide is a much simpler task. The highest yield I've obtained is ~21% hydrogen peroxide IIRC.
Boiling the same under vacuum takes a LONG time and causes a lot of decomposition in my experience. If you first concentrate by freezing then pull a
hard vac and maybe heat very gently, maybe you can up the concentration.
Under the right conditions, stabilized H2O2 can be concentrated somewhat just by setting a shallow glass pan out so some of the excess water
evaporates. The trick with this is keeping out dust and other airborne contaminants.
Chemical CURIOSITY KILLED THE CATalyst.
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