Ozone oxidiser?

[p1t1o]

Has Ozone (O₃) ever been considered as an oxidiser? Its a little more potent than O₂ in terms of oxidising potential, more reactive though, and more toxic.

[Starman4308]

If I'm recalling Ignition correctly, it was considered, but is just too unstable to deal with for very marginal improvement over standard liquid oxygen.

[KSK]

55 minutes ago, Starman4308 said:

If I'm recalling Ignition correctly, it was considered, but is just too unstable to deal with for very marginal improvement over standard liquid oxygen.

Yeah, horribly unstable and about as toxic as fluorine. Taking a quick flick through Ignition, there was also a phase separation problem apparently, at least for an ozone/oxygen mix. Oxygen boils off from residual oxidizer in your propellant lines, ozone gets more concentrated, mixture splits into two phases, one with 30% ozone, the other with 75%. The latter almost invariably goes kaboom for no reason whatsoever. Probably not a good idea to plan on restarting an ozone powered rocket stage at any point.

It's okay though - the phase separation problem can be overcome by adding a small amount of fluorine to your oxygen and ozone mix. Which clearly makes everything better.

 

[sevenperforce]

17 minutes ago, KSK said:

It's okay though - the phase separation problem can be overcome by adding a small amount of fluorine to your oxygen and ozone mix. Which clearly makes everything better.

I love this.

But yeah, ozone is a monopropellant in its own right, so it has a nasty tendency to do what hydrogen peroxide does, except worse.

[p1t1o]

Ah-ha, yep those are all good reasons.

I knew I should have gone straight to Ignition...

[KSK]

@sevenperforce  Again, from reading Ignition, I think that  was the big attraction of using ozone. An oxidiser that exothermically decomposes (yay, more energy) into a second, and rather good in its own right, oxidiser - what’s not to like?

 

Edited May 15, 2018 by KSK

[sevenperforce]

34 minutes ago, KSK said:

@sevenperforce  Again, from reading Ignition, I think that  was the big attraction of using ozone. An oxidiser that exothermically decomposes (yay, more energy) into a second, and rather good in its own right, oxidiser - what’s not to like?

I suppose the separation problems. And spontaneous ignition problems.

[kerbiloid]

-According to the article, <24% concentration is enough stable to be used in engines, but useless because adds just a little to pure oxygen.
While higher concentrations are unstable and flammable.

[sevenperforce]

A lovely and energetic discussion (no pun intended) on the use of liquid ozone as a propellant:

https://forum.nasaspaceflight.com/index.php?topic=13023.0

Oh, and an exciting bonus: if you mix ozone and fluorine, you can fill your tanks with it and make a turbine engine that will run in any atmosphere in the solar system!

(a mixture of ozone and fluorine will combust with equal enthusiasm whether it is mixed with the nitrogen in our air or with the carbon dioxide on Venus/Mars)

[sh1pman]

20 minutes ago, sevenperforce said:

A lovely and energetic discussion (no pun intended) on the use of liquid ozone as a propellant:

https://forum.nasaspaceflight.com/index.php?topic=13023.0

Oh, and an exciting bonus: if you mix ozone and fluorine, you can fill your tanks with it and make a turbine engine that will run in any atmosphere in the solar system!

(a mixture of ozone and fluorine will combust with equal enthusiasm whether it is mixed with the nitrogen in our air or with the carbon dioxide on Venus/Mars)

The best result would be in gas giant atmospheres.

Edited May 15, 2018 by sh1pman

[wumpus]

5 hours ago, sevenperforce said:

A lovely and energetic discussion (no pun intended) on the use of liquid ozone as a propellant:

https://forum.nasaspaceflight.com/index.php?topic=13023.0

Oh, and an exciting bonus: if you mix ozone and fluorine, you can fill your tanks with it and make a turbine engine that will run in any atmosphere in the solar system!

(a mixture of ozone and fluorine will combust with equal enthusiasm whether it is mixed with the nitrogen in our air or with the carbon dioxide on Venus/Mars)

Sounds like a way to reduce the problem of building a SCRAMJET booster into a single problem: keeping the fuel from exploding.  Oh, and launch your scramjet from a ground-based SRB, we don't want to lose a carrier aircraft as well.

[KSK]

6 hours ago, sevenperforce said:

A lovely and energetic discussion (no pun intended) on the use of liquid ozone as a propellant:

https://forum.nasaspaceflight.com/index.php?topic=13023.0

Oh, and an exciting bonus: if you mix ozone and fluorine, you can fill your tanks with it and make a turbine engine that will run in any atmosphere in the solar system!

(a mixture of ozone and fluorine will combust with equal enthusiasm whether it is mixed with the nitrogen in our air or with the carbon dioxide on Venus/Mars)

Sprinkle zamphor. Add an olive. Drink - but very carefully.

[sevenperforce]

14 minutes ago, wumpus said:

Sounds like a way to reduce the problem of building a SCRAMJET booster into a single problem: keeping the fuel from exploding.  Oh, and launch your scramjet from a ground-based SRB, we don't want to lose a carrier aircraft as well.

Also sounds like a way to reduce the problem of overpopulation in general.

[Zeiss Ikon]

1 hour ago, sevenperforce said:

Also sounds like a way to reduce the problem of overpopulation in general.

Only if you do it rather a lot.

[p1t1o]

18 hours ago, sevenperforce said:

A lovely and energetic discussion (no pun intended) on the use of liquid ozone as a propellant:

https://forum.nasaspaceflight.com/index.php?topic=13023.0

Oh, and an exciting bonus: if you mix ozone and fluorine, you can fill your tanks with it and make a turbine engine that will run in any atmosphere in the solar system!

(a mixture of ozone and fluorine will combust with equal enthusiasm whether it is mixed with the nitrogen in our air or with the carbon dioxide on Venus/Mars)

You'd have to make the turbine out of something that wont be consumed by a high pressure mix of ozone and fluorine at several hundred degrees. Something more inert than Nitrogen or Carbon Dioxide...Any idea what that material might be? 

[KSK]

1 hour ago, p1t1o said:

You'd have to make the turbine out of something that wont be consumed by a high pressure mix of ozone and fluorine at several hundred degrees. Something more inert than Nitrogen or Carbon Dioxide...Any idea what that material might be? 

Okay, this is pure spitballing because I haven't looked up the relevant numbers and my chemistry graduate days are far behind me, but I think fluorine is the stronger oxidising agent. I'm basing this on the fact that something like chlorine trifluoride will happily oxidise silicates (for example common sand) and fluorine itself will happily etch - well pretty much anything. Using it as an etchant in semiconductor fabrication is one of it's major industrial uses after all.

Fluorine will also form an inert metal fluoride layer on certain metals, so I'm thinking that with a suitable choice of alloy for your turbine, it ought to possible to passivate it by treating it with fluorine gas, at which point, further fluorine erosion should be prevented. The white elephant in the room here is obviously that ozone. I don't think it would oxidise a metal fluoride layer but I'm not sure.

I did also think that if you're really only looking at the lower end of a few hundred degrees for your operating temperature, then Teflon melts at 326 degrees Celsius. On reflection though, I expect ozone would chew up Teflon in short order - all those lovely, lovely carbon-carbon bonds to chow down on.

Edited May 16, 2018 by KSK

[sevenperforce]

2 hours ago, p1t1o said:

You'd have to make the turbine out of something that wont be consumed by a high pressure mix of ozone and fluorine at several hundred degrees. Something more inert than Nitrogen or Carbon Dioxide...Any idea what that material might be? 

Tungsten halfnium carbide?

30 minutes ago, KSK said:

Okay, this is pure spitballing because I haven't looked up the relevant numbers and my chemistry graduate days are far behind me, but I think fluorine is the stronger oxidising agent.

Yes, by far.

[p1t1o]

1 hour ago, KSK said:

Okay, this is pure spitballing because I haven't looked up the relevant numbers and my chemistry graduate days are far behind me, but I think fluorine is the stronger oxidising agent. I'm basing this on the fact that something like chlorine trifluoride will happily oxidise silicates (for example common sand) and fluorine itself will happily etch - well pretty much anything. Using it as an etchant in semiconductor fabrication is one of it's major industrial uses after all.

Fluorine will also form an inert metal fluoride layer on certain metals, so I'm thinking that with a suitable choice of alloy for your turbine, it ought to possible to passivate it by treating it with fluorine gas, at which point, further fluorine erosion should be prevented. The white elephant in the room here is obviously that ozone. I don't think it would oxidise a metal fluoride layer but I'm not sure.

I did also think that if you're really only looking at the lower end of a few hundred degrees for your operating temperature, then Teflon melts at 326 degrees Celsius. On reflection though, I expect ozone would chew up Teflon in short order - all those lovely, lovely carbon-carbon bonds to chow down on.

Metal fluoride passivation sounds like a pretty good answer actually, assuming that the mechanical properties of the layer are sufficient.

Teflon probably wont get damaged by ozone/fluoride (IIRC all those fluorine atoms protect the C-C bonds from oxidation) but it is an oxidiser in its own right and would probably react with the fuel.

 

44 minutes ago, sevenperforce said:

Tungsten halfnium carbide?

Very heat resistant, but in the presence of strong oxidising agents? I know that Tungsten Carbide reacts strongly with chlorine, unsure what that says about WHfC in Fluorine.

[KSK]

Okay - so I went there.

Looks like you’re spot on about ozone and Teflon. List of ozone resistant materials here. From a separate source, nickel also has an excellent rating - stainless steel resistance to ozone improves with higher nickel content.

And unsurprisingly after reading Ignition, fluorine has been studied as an oxidiser. NASA list of fluorine resistant materials here.

Nickel based superalloy for your turbine? Doesn’t look like an insurmountable problem at any rate.

[Thor Wotansen]

So the king of heat resistant steel alloys, inconel might just do the trick.  Can't wait to fly a F-104 in Jupiter's atmosphere.   

[p1t1o]

Noice

***

Ooops, made the classic mistake up there ^^^, typed "fluoride" instead of "fluorine".

Thats the chemist version of accidentally calling your teacher "mum".

And the dentist version of really, really screwing up at work.

**edit**

Heh, look at that, turns out turbine blades are already made of inconel...

 

Edited May 16, 2018 by p1t1o

[wumpus]

9 minutes ago, p1t1o said:

Noice

***

Ooops, made the classic mistake up there ^^^, typed "fluoride" instead of "fluorine".

Thats the chemist version of accidentally calling your teacher "mum".

And the dentist version of really, really screwing up at work.

**edit**

Heh, look at that, turns out turbine blades are already made of inconel...

Which means that the boundary temperature gets nasty, and if your fluorine/ozone mix gets any hotter the blades are in big trouble.

I'd hate to think what would happen to turbine blades on Venus, and have always considered this a "burn nitrogen on Earth" thing, so use a scramjet to >mach 10 or so (first stage).  I guess it allows for heavier craft than 1kg helicopters on Mars, but fixed wing craft there doesn't sound any more sane.  Do any of the moons of Jupiter (or Titan) have atmospheres (at least more than Mars)?

[VaPaL]

1 hour ago, p1t1o said:

Heh, look at that, turns out turbine blades are already made of inconel...

Yep, Inconel is a great alloy, but very hard to work with. It consumes machining tools like crazy and it's not the most easy one to cast either. Let alone the problems of casting a turbine disk due to it's complex geometry.

But some turbopump turbine blades have to deal with temperatures reaching 1000K+ in a oxidizer rich environment and are made of inconel, so it should do the work.

 

EDIT:

There's also an alloy on Tungsten-Rhenium-Hafnium-Carbon that is very resistant at high temperatures and I found a Tantalum-Hafnium Carbide (another paper) ceramic that is also very resistant to heat and somewhat more resistant to oxidation than Tantalum Carbide or Hafnium Carbide alone, but as a ceramic it's problably to brittle for this application (still interesting though).

Edited May 16, 2018 by VaPaL

[p1t1o]

47 minutes ago, VaPaL said:

Yep, Inconel is a great alloy, but very hard to work with. It consumes machining tools like crazy and it's not the most easy one to cast either. Let alone the problems of casting a turbine disk due to it's complex geometry.

But some turbopump turbine blades have to deal with temperatures reaching 1000K+ in a oxidizer rich environment and are made of inconel, so it should do the work.

 

EDIT:

There's also an alloy on Tungsten-Rhenium-Hafnium-Carbon that is very resistant at high temperatures and I found a Tantalum-Hafnium Carbide (another paper) ceramic that is also very resistant to heat and somewhat more resistant to oxidation than Tantalum Carbide or Hafnium Carbide alone, but as a ceramic it's problably to brittle for this application (still interesting though).

Thats a good point actually, should have thought about LOx turbopumps straightaway.

 

 

1 hour ago, wumpus said:

Which means that the boundary temperature gets nasty, and if your fluorine/ozone mix gets any hotter the blades are in big trouble.

Its not like a fluorine/ozone turbojet will always run hotter than a conventional one, just that the chemical environment inside will be much more harsh.

 

1 hour ago, wumpus said:

  Do any of the moons of Jupiter (or Titan) have atmospheres (at least more than Mars)?

Yes, definitely, I cant remember off the top of my head which one has what, but there are various ones. I have a vague memory of one of them even having an atmospheric pressure similar to Earth, I forget which. I think it might be Titan. *googlygoogle* Yep, Titan has a surface pressure of 1.45atm, mostly nitrogen, and with a surface gravity of around 0.1-0.2G, flying there would be easy as pie. If you get propulsion to work.

[sevenperforce]

10 minutes ago, p1t1o said:

Yes, definitely, I cant remember off the top of my head which one has what, but there are various ones. I have a vague memory of one of them even having an atmospheric pressure similar to Earth, I forget which. I think it might be Titan. *googlygoogle* Yep, Titan has a surface pressure of 1.45atm, mostly nitrogen, and with a surface gravity of around 0.1-0.2G, flying there would be easy as pie. If you get propulsion to work.

A touch chilly though, I reckon.