209
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Hydrogen peroxide
Being that in high levels of concentration, this sure as hell is an energetic material, thought it would be best to post here. I have latly beeing
looking a lot at rocket belts and other thrust propultion ideas. I know you can concentrate H202 from 3% to about 30% without it decomposing, but
thats not good enough. I need concentrations up to 85-90% concentrations, any ideas on how to concentrate it this high? Obviously I would need massive
amounts of H202, but I think I know were I can get it. Any ideas?
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ssdd
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I would think somewhere there would be a thread on this...
But I did some searching and didn't seem to find much.
But I also would be interested in this because I am sick of 3% and my experiments not working because of it.
If someone has anything I'll keep looking...
Would it be simpler to buy 30% and try and concentrate that?
-ssdd
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hashashan
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you should distill it. the procedure is quite risky. and of course it will be simpler to buy 30%. you have 10 times more H2O2 there then in the 3%
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roamingnome
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phase diagrams
are your friend
http://www.h2o2.com/intro/properties/physical.html
try dry ice first...
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gregxy
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There is a long thread on this but I didnt see that anyone made it work for 3%. I tried the freezing method. Supposedly the water freezes at a higher
temp and you pull out the block of water ice leaving more highly concenterated peroxide. However for me it just froze solid. I think that all of the
H2O2 ended up trapped in small cracks in the ice.
For making HMTD and the like there is a company on EBAY that sells little 30ml bottles of 30%. More that enough to blow off all of your fingers.
For a rocket you are going to need kilos of it so you would need to find a source to sell you the concentrated stuff. People make rockets that run on
pure peroxide but that seems like a waste of oxygen. Better to figure out how to use peroxide and alcohol. Or else use N2O and salami like the
Mythbusters.
There is this cool video of a guy that made a "personal jet" with a 6 foot wing span. It is powered by 4 big model airplane jet engines. It could not
take off from the ground but he would jump out of an airplane and fly around for about 5 minutes before he burned up all his gas, then he opened a
parachute and floated down.
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mbrown3391
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try a local beauty supply store. I can get large bottles (half liter) of 40% h2o2 for 4 bucks!
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not_important
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| Quote: | Originally posted by mbrown3391
try a local beauty supply store. I can get large bottles (half liter) of 40% h2o2 for 4 bucks! |
Forty percent or forty volume? All the beauty supply peroxide I've seen isn't above 12%, most comes labeled as 10, 20, 30, 40, or 50 volume.
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not_important
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When using the freezing method you must lower the temperature very slowly, in order to get the ice to form as a solid block.
Alternatively you can freeze the solution, drain off and collect any liquid, crush the ice, and drain off and collect the liquid from it - letting the
ice slightly melt.
If you check the reference roamingnome posted, you'll see that water freezes out down to about -50 C, and 50% concentration. The freezing point as
degrees C below zero is roughly the percentage of H2O2, in a handwaving sort of fashion.
You don't distill the peroxide, you distill or evaporate off the water. Use reduced pressure, a water bath, and don't heat about 50 or 60 C.
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hashashan
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will the freezing method work for 3%?
i have this thought the the 3% stuff is a byproduct of 90% production via freezing method. i mean the ice collected that contins some peroxide .. 3%
maybe>?
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The_Davster
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As not_important mentioned, I have read several papers in which 30% was concentrated to 80-90% using a rotovap and reduced pressure.
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not_important
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| Quote: | Originally posted by hashashan
will the freezing method work for 3%?
i have this thought the the 3% stuff is a byproduct of 90% production via freezing method. i mean the ice collected that contins some peroxide .. 3%
maybe>? |
Freezing is for people who don't have the equipment to do the evaporation method, or who think that "warming" means any temperature that doesn't melt
the flask. I doubt that it is used industrially.
And as I said and the phase diagrams show, you can't get much above a concentration of 50% peroxide by freezing out water. At concentrations between
50 and 60 percent a mixture of H2O2 and H2O freezes out, at still higher concentrations H2O2 itself freezes out. So the 'ice' from really strong
peroxide is nearly 100% H2O2, and you can't concentrate a solution in water above about 60% - the eutectic point.
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franklyn
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How many more times
http://www.sciencemadness.org/talk/viewthread.php?tid=1325&a...
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vulture
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And that closes this thread...
One shouldn't accept or resort to the mutilation of science to appease the mentally impaired.
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