megalomania
June 10th, 2003, 02:06 PM
phyrelord
Frequent Poster
Posts: 135
From:
Registered: JAN 2001
posted 05-17-2001 10:38 PM
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I don't know if this has been mentioned before but I found it interesting. I found this while looking for info on H202 rockets. you can approach 62 percent pure hydrogen peroxide.
Can I concentrate H2O2 myself by freezing?
Yes, you can, but there are has limits on how much water/H2O2 that can be removed by simple freezing. The problem is that at 62% H2O2/H2O solution the peroxide and water freeze together to form an H2O/H2O2 ice. Thus whether you are freezing a water rich solution or a hydrogen peroxide rich solution the remaining liquid tends to become a 62% solution where both substances blend and freeze together.
Can I concentrate H2O2 myself by freezing out the water?
Yes, you can, when H2O2 is a small percentage of the solution i.e. less than 40%, the ice that forms is mainly water, so that the percentage of H2O2 left in solution steadily increases as more ice forms. However, some of the H2O2 freezes in the ice also, so there is a loss that gets worse as the percentage of H2O2 approaches 62%. This is a useful and easy way to concentrate very weak H2O2 solutions however. Notice will this process really tends to leave any contaminates in the solution.
Can I concentrate H2O2 myself by freezing out the H2O2?
Yes, you can, but there are has limits on how much H2O2 can be removed by simple freezing. If you start with a 90% or higher H2O2/H2O solution the ice that forms is almost pure H2O2, however the same limits still apply. As you freeze more and more of the H2O2 the percentage of water in solution climbs, and so does the amount of water that freezes in the ice. Again, the freezing will balance at 62%.
CragHack
Frequent Poster
Posts: 618
From:
Registered: DEC 2000
posted 05-18-2001 10:32 AM
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this has actually been mentioned before, but you provided a VERY usefull peice of info. When we talked about it earlier no one knew the percentage with which your H2O2 could be frozen too. You said 62%. If this is correct then kudos to you. May i ask where you got your information?
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"If you must, do it with intelligent people, at least they know how to talk to the cops."
PYRO500
Moderator
Posts: 1465
From: somewhere in florida
Registered: SEP 2000
posted 05-18-2001 04:05 PM
--------------------------------------------------------------------------------
something that will cause you trouble is that H2O2 freezes right after water so it complicates things.
zaibatsu
Frequent Poster
Posts: 407
From: England
Registered: SEP 2000
posted 05-18-2001 04:10 PM
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Why (other than rockets) would you want to go to the trouble of increasing the % of H202?
phyrelord
Frequent Poster
Posts: 135
From:
Registered: JAN 2001
posted 05-18-2001 04:14 PM
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I was searching a site on H2O2 rockets, it was some site on yahoo. It had a lot of info and seemed pretty acurate so I would trust it. I would treat the process a lot like distillinging by keeping the temperature very close to freezing point of water but not high enough to freeze the H2O2. If I'm right I think 62 percent would get you a lot higher yield than 3 or 6 percent when used in making AP.
zaibatsu
Frequent Poster
Posts: 407
From: England
Registered: SEP 2000
posted 05-18-2001 04:23 PM
--------------------------------------------------------------------------------
It would IF you had say 100ml 3% h202 and 100ml 62%. But you are just removing the water, leaving you with the same amount of H202, just less water. Say you had 100ml 3% H202, and you concentrated that to 62%. You would be left with about 4.8ml of 62% H202 (if my calculations are correct). In the first case you have 3ml of pure H202, and in the second case you have 3ml pure H202. The only thing that differs is the amount of water.
------------------
Handguns don't kill people... Half as well as full-auto
Visit me at www.surf.to/eliteforum
FadeToBlackened
Frequent Poster
Posts: 201
From: Hell
Registered: MAR 2001
posted 05-18-2001 05:07 PM
--------------------------------------------------------------------------------
A while back there was a post (i think there was anyway) about boiling a weak solution so much and getting about 12% H2O2. Does anyone have any info on this? I haven't been able to find the post...
blackadder
Frequent Poster
Posts: 313
From: London
Registered: DEC 2000
posted 05-18-2001 06:55 PM
--------------------------------------------------------------------------------
At my school they have some lab concentration H2O2 which I would like to "borrow".
Does anyone know what percentage of that would be H2O2? It has a "corrosive" sign on it, and it's inside a brown bottle (to prevent decompostion of the hydrogen peroxide upon contact with light). Since it has a "corrosive" sign on it, I'm thinking it's pretty high concentration of H2O2.
CodeMason
Frequent Poster
Posts: 383
From: Your Nightmares
Registered: NOV 2000
posted 05-19-2001 08:59 PM
--------------------------------------------------------------------------------
It is almost certainly 30% (lab grade), but perhaps they needed some really conc. H2O2 for some special purpose...
Frequent Poster
Posts: 135
From:
Registered: JAN 2001
posted 05-17-2001 10:38 PM
--------------------------------------------------------------------------------
I don't know if this has been mentioned before but I found it interesting. I found this while looking for info on H202 rockets. you can approach 62 percent pure hydrogen peroxide.
Can I concentrate H2O2 myself by freezing?
Yes, you can, but there are has limits on how much water/H2O2 that can be removed by simple freezing. The problem is that at 62% H2O2/H2O solution the peroxide and water freeze together to form an H2O/H2O2 ice. Thus whether you are freezing a water rich solution or a hydrogen peroxide rich solution the remaining liquid tends to become a 62% solution where both substances blend and freeze together.
Can I concentrate H2O2 myself by freezing out the water?
Yes, you can, when H2O2 is a small percentage of the solution i.e. less than 40%, the ice that forms is mainly water, so that the percentage of H2O2 left in solution steadily increases as more ice forms. However, some of the H2O2 freezes in the ice also, so there is a loss that gets worse as the percentage of H2O2 approaches 62%. This is a useful and easy way to concentrate very weak H2O2 solutions however. Notice will this process really tends to leave any contaminates in the solution.
Can I concentrate H2O2 myself by freezing out the H2O2?
Yes, you can, but there are has limits on how much H2O2 can be removed by simple freezing. If you start with a 90% or higher H2O2/H2O solution the ice that forms is almost pure H2O2, however the same limits still apply. As you freeze more and more of the H2O2 the percentage of water in solution climbs, and so does the amount of water that freezes in the ice. Again, the freezing will balance at 62%.
CragHack
Frequent Poster
Posts: 618
From:
Registered: DEC 2000
posted 05-18-2001 10:32 AM
--------------------------------------------------------------------------------
this has actually been mentioned before, but you provided a VERY usefull peice of info. When we talked about it earlier no one knew the percentage with which your H2O2 could be frozen too. You said 62%. If this is correct then kudos to you. May i ask where you got your information?
------------------
"If you must, do it with intelligent people, at least they know how to talk to the cops."
PYRO500
Moderator
Posts: 1465
From: somewhere in florida
Registered: SEP 2000
posted 05-18-2001 04:05 PM
--------------------------------------------------------------------------------
something that will cause you trouble is that H2O2 freezes right after water so it complicates things.
zaibatsu
Frequent Poster
Posts: 407
From: England
Registered: SEP 2000
posted 05-18-2001 04:10 PM
--------------------------------------------------------------------------------
Why (other than rockets) would you want to go to the trouble of increasing the % of H202?
phyrelord
Frequent Poster
Posts: 135
From:
Registered: JAN 2001
posted 05-18-2001 04:14 PM
--------------------------------------------------------------------------------
I was searching a site on H2O2 rockets, it was some site on yahoo. It had a lot of info and seemed pretty acurate so I would trust it. I would treat the process a lot like distillinging by keeping the temperature very close to freezing point of water but not high enough to freeze the H2O2. If I'm right I think 62 percent would get you a lot higher yield than 3 or 6 percent when used in making AP.
zaibatsu
Frequent Poster
Posts: 407
From: England
Registered: SEP 2000
posted 05-18-2001 04:23 PM
--------------------------------------------------------------------------------
It would IF you had say 100ml 3% h202 and 100ml 62%. But you are just removing the water, leaving you with the same amount of H202, just less water. Say you had 100ml 3% H202, and you concentrated that to 62%. You would be left with about 4.8ml of 62% H202 (if my calculations are correct). In the first case you have 3ml of pure H202, and in the second case you have 3ml pure H202. The only thing that differs is the amount of water.
------------------
Handguns don't kill people... Half as well as full-auto
Visit me at www.surf.to/eliteforum
FadeToBlackened
Frequent Poster
Posts: 201
From: Hell
Registered: MAR 2001
posted 05-18-2001 05:07 PM
--------------------------------------------------------------------------------
A while back there was a post (i think there was anyway) about boiling a weak solution so much and getting about 12% H2O2. Does anyone have any info on this? I haven't been able to find the post...
blackadder
Frequent Poster
Posts: 313
From: London
Registered: DEC 2000
posted 05-18-2001 06:55 PM
--------------------------------------------------------------------------------
At my school they have some lab concentration H2O2 which I would like to "borrow".
Does anyone know what percentage of that would be H2O2? It has a "corrosive" sign on it, and it's inside a brown bottle (to prevent decompostion of the hydrogen peroxide upon contact with light). Since it has a "corrosive" sign on it, I'm thinking it's pretty high concentration of H2O2.
CodeMason
Frequent Poster
Posts: 383
From: Your Nightmares
Registered: NOV 2000
posted 05-19-2001 08:59 PM
--------------------------------------------------------------------------------
It is almost certainly 30% (lab grade), but perhaps they needed some really conc. H2O2 for some special purpose...