Liquid Dinitrogen Tetroxide

[shannon dove]

Does anyone have any information or experiance with using liquid N2O4 as an oxidizer in explosives such as gasoline/N2O4 ,benzene/N2O4, or nitrobenzene/N2O4(nitrobenzene could use more oxygen than it has)?I know that nitric acid is used with combustables such as nitrobenzene,but what about liquid N2O4? Teny Davis does mention it in the book "The chemistry of powder and explosives",but he does not say a lot about it,only one paragraph and that is it.What about making NO2 using nitric acid and copper then condensing the gas in a container surrounded by dry ice?(NO2 turns into N2O4 when liquified). Yes I did search first ,I found nothing.

[megalomania]

This sounds quite messy, dangerous, and impractical from an industrial or military perspective, which is likely why you are having trouble finding information; it would be rare to nonexistant. IIRC there may be something in the Urbanski books.

[nbk2000]

One thing you could search for is a paragraph break. :p

[shannon dove]

I understand that nobody likes the idea of using N2O4 based explosives.Let me explain some reasons why someone might on a rare occasion use it. There are many ways of making of making NO2, if you make it by heating anhydrous calcium nitrate you do not need concentrated nitric acid,you do not need sulfuric acid, all you need is dilute nitric acid and calcium carbonate to make calcium nitrate.If you make NO2 by electrylises of molten pottasium nitrate then all you need is KNO3 and D.C. electricity,you do not need nitric acid at all, assuming you allready have KNO3.If you cannot get dry ice, no problem, as regular ice would most likely be cold enough to condense NO2 into a liquid, as the boiling point is about 70 degrees F. Yes I know that it is dangerous, but I was thinking that the N2O4 would not be mixed with a fuel until it is ready to be used, and then it would be mixed remotely with the person using it being far away. Also if you have no liquid fuel ,thats not a problem either ,just soak charcoal in N2O4 the way liquid oxygen was once used. My point is that N2O4 can be made without hard to get chemicals such as concentrated nitric acid, and there are so many ways to make it.

[megalomania]

That is an interesting perspective. Let me tell you mine. You can’t get nitric acid in any form, dilute or otherwise. You can’t get any nitrate salts in more than sub kilogram quantity without a fedgov inquiry. You can’t get this stuff without being connected, and by that I mean a school, company, factory, or other legitimate lab. If you can acquire nitric acid, good for you, you are one in a million in this world.

You can make your own, certainly this is possible, but it takes some work. I know; I have been working on it for years, on and off. I could get it by the drum, but I place the same restrictions on my research as would be faced by the vast majority of people in the world. Under such restrictions getting or making nitric acid is very difficult.

Incidentally, if you already have dilute nitric I would add copper to it and collect the nitrogen dioxide fumes. Add an excess of copper to the dilute acid, gently heat, and collect the fumes in a cold trap. A dry ice bath is a good idea for that since nitrogen dioxide forms dinitrogen tetroxide under -10 C.

[shannon dove]

One problem I can see with using nitric acid/copper reaction is that there might be a little acid vapor mixed with the NO2 gas, espcially since the acid/copper should be warmed. If someone used the method of heating annhydrous calcium nitrate until it decomposes, I think the NO2 would be 100 percent annhydrous. I think a little acid mixed with the liquid N2O4 would make it extremely corrosive, if it is annhydrous, then a metal container should work fine for storing it.

I did some more searching about N2O4 explosives and found out that a guy named turpin made some explosives using N2O4 in the 1870s. He said that some of these explosives were the most powerful in the world! I do not know if he had facts to back up this claim, but just the fact that he said that means something.

I know that in the 1870s explosives such as nitroglycerine had been made, so according to Turpin, liquid N2O4 based explosives are more powerful than nitroglycerin!

[Bugger]

I have heard of liquid N2O4 being used by NASA as the oxidizer in rocket engines, reacted with a suitable combustible substance to produce hot gases with an exceptionally high rate of expansion for propulsion. I think it has been reacted variously with liquid N2H4, NH3, and light hydrocarbons, fir the purpose.

[reamio]

It is currently used by NASA on the space shuttle's reaction control system (RCS) jets.

http://science.ksc.nasa.gov/shuttle/technology/sts-newsref/sts-rcs.html

In fact, after the shuttle lands, an extensive purging/venting procedure with nitrogen is carried out on all of the RCS thrusters before anyone is allowed to get near the spacecraft:eek: .

[sparkchaser]

Wasn't that what they used to win the X Prize? N2O4 for oxidizing a rubber matrix? I think N2O4 mixed with a hydrocarbon liquid would be just a touch unstable for that perpose though. Any welder knows that oil on a compressed oxygen fitting will detonate spontaneously, wouldn't this do the same?

[FUTI]

Wasn't that what they used to win the X Prize? N2O4 for oxidizing a rubber matrix? I think N2O4 mixed with a hydrocarbon liquid would be just a touch unstable for that perpose though. Any welder knows that oil on a compressed oxygen fitting will detonate spontaneously, wouldn't this do the same?

I think you are wrong about X Prize winner vehicle used NO2...it was N2O AFAIR.

Yes NO2 is used as rocket fuel mostly in combination with N2H4 (or organic amines mixtures). It is so toxic/corrosive that people prefer to use concentrated H2O2 instead (and we all know how bloody tricky that is) - old surface to air missile use NO2 as oxidant and crew that prepare those rocket had to work in scafanders with oxigen bottles. Russians by some reports use NO2 in its kerosine/liquid oxygen systems although I never read that in their reports. In launch preparation Russians say they pump "nitrogen"...now is it really nitrogen or NO2 written funny to mask its there I don't know. Maybe it is really nitrogen and they use some complex cycle where they use exotermic reaction of hydrocarbon combustion to drive endotermic reaction of making NOx in first chamber which drives turbopump and since they use close cycle engines where combustion gases from first chamber enter the second (main) chamber enhance the combustion proces in it with NOx?