oriansbelt Posted January 27, 2007 Posted January 27, 2007 I put this in here because it doesn't really pertain to pyro but isn't quite general discussion. Well what I was wondering is if it would be possible to make hydrogen peroxide from water, something like this?H2O+O2 > H2O2+OOr something, I don't know much about chemistery so if that doesn't make sence, sorry. I tried searching the web but found nothing on this subject so I thought I'd ask here. Has any one heard of any way to make H2O2 that doesn't involve chemicals like 2-ethyl-9 and 10-dihydroxyanthracene to 2-ethylanthraquinone and hydrogen peroxide? That is the comercial way of doing it but I want one that more experimentaion friendly. Thanks for any help you can give me.
asilentbob Posted January 28, 2007 Posted January 28, 2007 I remember reading something about electrolyzing a sulfate into a persulfate, then doing something from there... might find some relavent info at SMDB... did you search?
oriansbelt Posted January 28, 2007 Author Posted January 28, 2007 What is SMDB? I did serach but found nothing on making it on a small scale. The closest I got was a mention of an electrolitical process but I also found some thing that said it was made naturally from sun light reacting on water so I was skeptical.
rocket Posted January 28, 2007 Posted January 28, 2007 SMDB stands for Science Madness Discussion Board.Here’s the link: http://www.sciencemadness.org/talk/
Douchermann Posted January 28, 2007 Posted January 28, 2007 H2O + O2 wont work, however H2O + O3 ----> H2O2 + O2 Ozone is easily produced if you have a neon sign transformer. I recently made one. I would post pictures of it, but I'm filling a wine cellar with ozone to kill off the mold at my buddies house.
oriansbelt Posted January 29, 2007 Author Posted January 29, 2007 Thanks, so would I just bubble the ozone up through the water to react it or would it be more complicated? Again I'm using my nonchemistery minded brain and thinking H2 + O2 would be easiest but I don't know if that is even possible.On a side note, does any know if I could distill it to consentrate it after I make it? Thanks for the help, I did find some good stuff on SMDB.
Mumbles Posted January 29, 2007 Posted January 29, 2007 Yes, you bubble ozone into water to form hydrogen peroxide. It will form very weak solutions though and must be concentrated to do anything usefull. You can distill it, but at the low concentrations they boil at a very similar temp and are difficult to separate. I find the best method of concentration is by steaming. Heat the solution to 80C or so to steam off the water, but it will leave a majority of the H2O2 left. This does only work up to a point though. Generally the accepted method of concentration is by freezing out the water up to 63%(azeotrope), and then vacuum distillation can be used up to near 100%. The steaming can get you up around 30%, which is acceptable for anything you'd be trying really.
oriansbelt Posted January 30, 2007 Author Posted January 30, 2007 Are u saying that you can get it 62% pure with freezing or freeze untill 62% of the liquid has frozen? Thanks for all the help. My purpose actually is to make a hybride rocket(engine) fueled with H2O2. I would need around 85% pure stuff for that so I wanted to make sure I could make that before I started on the engine itself. I know it is a very high goal for an amature to try making a hybrid with no former experiance with liquid fueled rockets but I thought I'd try cuz I love rockets and a H2O2 hybrid is pretty simply in the realm of hybrids.
DeAdFX Posted January 30, 2007 Posted January 30, 2007 You can get a mixture of 62% H2O2 and 38% water by freezing. Making it isn't going to be very economical unless you have a vacuum distallation setup. Why not make a liquid hydrogen peroxide rocket? You could use a basic fuel like ammonia/triethanol amine/diethanolamine/etc and complex with a copper compound like copper cyanide. That way when the fuel and peroxide meet together you will have spontaneous ignition [ no need to have an igniter system].
oriansbelt Posted January 30, 2007 Author Posted January 30, 2007 Ok thanks, at least 62% will be closer to what I want, maybe I could use it just to show how a H2O2 rocket would work. Am I right in asuming that I just take any ice out that forms if I keep the temperature between -11C and 0C? Or is it something more complicated because I've been confused by the way the freeze purification method has been explained in other places that I have found. And I think I might go with buying the peroxide at 35% pure so that should make things a little simpler.Well the engine I was planning on would use silver screens to decompoze it to H2O and O at a very high temp. then I would have a solid fuel grain(poly..somethingsomething, I think wax will work too so I might go with that) to utilize the O thus making it a hybrid. This set up is also no ignition since all I have to do it but the H2O2 on the silver to start that reaction and the heat from that will ignite the fuel grain part.
hashashan Posted January 30, 2007 Posted January 30, 2007 are you aware that H2O2 in high concentrations detonates?
pa_pyro Posted January 30, 2007 Posted January 30, 2007 I would phrase that as "capable of detonating" instead of saying it flat out deonates at higher percentages. In my experience freezing low percentage(3% and lower concentrations)isn't a great way of producing higher % H2O2. Unless you have precise temp control freezing isn't the way to go, awile ago when I tried freezing 3% the whole mass froze into a clump of ice. Removing the liquid when the mix started to turn slushy resulted in a slightly higher percentage peroxide. Mumble's steaming method seems to work rather well, maybe you should start with 27% H2O2(baquacil oxidizer) and either distill or steam off the water and go from there. The sodium percarbonate method from SMDB doesn't work because the peroxide decomposes while in a basic solution IIRC.
oriansbelt Posted January 31, 2007 Author Posted January 31, 2007 I am aware that H2O2 can be detonated at high concentration but as I said I don't want to get it any higher than 85% so it shouldn't be that dangerous. The minimum I have heard that peroxide works for rockets is 70% so if I start with the 35%(or 27% but I got a quart of the 35% stuff to test concentration on) so I just need to a little more than double the purity for use as fuel. Does anyone know how I could test the purity so that I know when I get to 70% if I try the freezing method or steaming?
hashashan Posted January 31, 2007 Posted January 31, 2007 You can test the concentration by density. and IIRC it is capable to detonate in concentrations above 70%. and it gets much more sensitive when heated so distilling it can be fairly dangerous
Serenius Posted February 2, 2007 Posted February 2, 2007 To above poster: But isn't that why you distil it under vacuum, so that you don't have to have such a high temperature? Or am I missing something?
Mumbles Posted February 2, 2007 Posted February 2, 2007 Yep, it is distilled under vacuum in and EXTREMELY clean still. Even dust can make it detonate at those concentrations I've heard.
hashashan Posted February 2, 2007 Posted February 2, 2007 And i didn't even mention that your distillation equipment cant be OTC because vacuum distillation is a tricky thing by itself. i don't even want to imagine what happens when a liter glass container with hot 70% H2O2 inplodes near me.
ewest Posted February 3, 2007 Posted February 3, 2007 This reminds me of something that happened over the summer in Houston. Two morons were making peroxide based something or other (in the bathtub in heard) and it exploded killing one of them. Texas City Apartment Explosion
Douchermann Posted February 3, 2007 Posted February 3, 2007 This reminds me of something that happened over the summer in Houston. Two morons were making peroxide based something or other (in the bathtub in heard) and it exploded killing one of them. Texas City Apartment Explosion Morons like that give pyro/home chemistry a bad name. Back to the matter at hand;Mumbles, could you not continue bubbling ozone into the water until it reached a more concentrated solution, especially if the water was kept cold?
DeAdFX Posted February 3, 2007 Posted February 3, 2007 Peroxide is supposedily(sp) "decomposed" by ozone too. The reaction between the two first forms Hydrogen Trioxide which is highly unstable and then decomposes to oxygen and water. I think the concentration of Peroxide will eventually hit the ceiling.
oriansbelt Posted February 3, 2007 Author Posted February 3, 2007 This reminds me of something that happened over the summer in Houston. Two morons were making peroxide based something or other (in the bathtub in heard) and it exploded killing one of them. Texas City Apartment ExplosionIt says those guys were making TATP, not just working with peroxide. It's no supprise they blew themselves up. But on a side note what would it take to detonate 70 through 85% H2O2? I'm not buying that a piece of dust is all that would do it cuz they use 90-99% for jet packs and I wouldn't strap hydrogen peroxide to my back if a piece of dust could detonate it. I think that "detonating by dust" comes from that if the right chemical in dust form were to fal on the peroxide it would decompose very fast and kinda go boom, not actually go though the prosses of detonation. Following is a link to the only manufactorer of jetpacks and how they use 90-99% H2O2 in their product. http://www.tecaeromex.com/ingles/destilai.htm
Mumbles Posted February 3, 2007 Posted February 3, 2007 The dust thing is for the very concentrated stuff. You have to understand there is a difference between distilling H2O2 and having it detonate and having a spray of vapor, which is most cases don't detonate. Theres no containment, and a very small amount of H2O2 in the spray from a jet pack. To be fair, I wouldn't strap a jet pack to my person period, no matter the fuel.
oriansbelt Posted February 5, 2007 Author Posted February 5, 2007 Well getting back to the main point of this topic, I was thinking that instead of bubbling O3 through water it would be more effiecient to spray water in a fine mist through ozone. Would that work better? I was figuring on having a box that has an ozone generator on one side and misters on the cielling and a basin on the other side with a showercurtain deviding them that can be moved from outside the box. The curtain would be pulled back and the ozone generator would be turned on and that would circulate the air inside around until as much as possible ozone was biult up(maybe for more efficientcy pure O2 could be pumped in first). Then, the curtain would separate the generator to protect it and water would be misted down through the ozone and collect in a basin at the bottem that would have a tap on the out side. One side of the box would open to allow new air to come in. How does that sound for a H2O2 rig?
Douchermann Posted February 7, 2007 Posted February 7, 2007 Might not be worth it. I think what DeAdFX said is possible, and if it's true, then it's not the efficiency of the generator, its the fact that it can only make so much chemically.
oriansbelt Posted February 7, 2007 Author Posted February 7, 2007 Well I figured that this was a way around that. I mean if the water is going through the ozone then it will react as it falls down to the bottem and not come into more contact with the ozone so it wouldn't become hydrogen trioxide. I guess that would actually depend on what hieght it was falling from but if it fell for the right amount of time it would just become H2O2 and not have time to get to H2O3 right?
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