Sodium Nitrate based Rockets

[moof]

Hello,

 

In the past, I've utiliized KNO3 as the primary oxidizer.

 

I can currently only gain access to NaNO3 and I was wondering if anyone had expereince using that in rocket forumulations as the primary oxidizer.

From my understanding, it's harder to work with as it is hard to keep dry and is less powerful than KNO3 based formulations.

 

Besides those things and creating a more yellow looking tail and changing up the ratios a bit, is there anything else I should keep in mind when working with this?

Any good formulas or resources? The ones I've seen are just replacing the KNO3 in sugar and BP formulations.

 

Thanks.

[Seymour]

It should potentially be more powerful rather than less as far as I'm aware. Sodium is a lot lighter than Potassium, so Sodium nitrate will have a higher oxygen content. Following on from this, you need less oxidiser and can fit more fuel per unit of rocket mix.

 

If you keep it dry it'll work great. If you keep it dry. I've not fully achieved this in all my past experience and with whatever moisture it had absorbed made it sluggish burning at best, and literally fully dissolved in a self made puddle which absorbed more water and overflowed from the dish in the worst case.

 

Good luck. Potentially you will get great power and as you said, a great yellow flame.

 

I do however think just sourcing KNO3, even if it's not straightforward for you, will be much easier.

[Mumbles]

I agree with Seymour. Under optimal conditions it is more powerful. That's going to depend on formulation, and a big part if you can keep it dry. They make a blasting powder based on it. It's the FB's, instead of FA's you typically see. It is typically a less bristant explosive. Whether that is strictly formulation or just accepting some slowing due to water I really don't know.

 

I know a few people who have managed to create some downright frightening rockets from it. I've been told the trick is to use it dry and use a water resistant binder to add some storage stability.

[mabuse00]

At least with organic fuels Sodium nitrate will be slower.

I tried to use it as rocket fuel bound in epoxi, what would hopefully alleviate the moisture problems to some extent.

 

I casted several epoxi mixtures with different oxidisers in paper tubes and measured the time. Compared to Potassium nitrate, the Sodium nitrate variants where much slower and some did not even manage to burn stable.

 

With proper stoichiometry you get more energy per gram of fuel, but you will need longer spindles and/or tighter nozzles for optimal performance.

[schroedinger]

If you can source NaNO3 god, just look around to source some Pottasium chloride, as it is vey esay to make Pure KNO3 with both together

[FlaMtnBkr]

Are you not in the US? KNO3 can be found as stump remover at the hardware store as a last ditch source.

 

If you do try the NaNO3 I would try making it like whistle with oil and solvent, or maybe with NC lacquer or phenolic resin and (pure) alcohol. You definitely don't want to add water after drying.

 

I wonder if you dampen with a solvent and then press and corn, dry it again, and then spray it with a dilute NCL, If it would seal it long enough to use it before absorbing water. But that would require a press since the grains would be so hard which most people don't have.

[moof]

Thanks for the responses.

 

I was thinking of using mineral oil or melted petrollium jelly like I see in whistle rocket compositions in order to have something displace the water. If I do that and store my completed motors and loose composition with desiccants, will this remove the issue of NaNO3 being to hydroscopic?

 

I've also heard somewhere that people sometimes use motor oil for that purpose, but I'm not sure of the results with that.

 

Also, is NaNO3 + S + C blackpowder ram and milling safe?

[mabuse00]

Depends on the climate where you live. In most cases, I'd say yes.

 

Also, is NaNO3 + S + C blackpowder ram and milling safe?

Yes (As safe as such things can be called "safe"...).

[Flaky123]

Great idea!

 

NaNo3 is much cheaper!

[FlaMtnBkr]

KNO3 can be less than a $1 per pound for agriculture stuff. I think the benefits over the sodium version far out weigh the small price difference if you can get KNO3. Even if paying 2 or 3 times as much it is worth it not to have to deal with the water, the increased amount of work necessary, and the questionable performance.

 

Personally I would pay the $4 per pound for stump remover KNO3 to be able to make regular BP. I deal with drying ammonium nitrate for exploding targets and it is a pain in the butt.

[Seymour]

I was thinking of using mineral oil or melted petrollium jelly like I see in whistle rocket compositions in order to have something displace the water. If I do that and store my completed motors and loose composition with desiccants, will this remove the issue of NaNO3 being to hydroscopic?

 

I've also heard somewhere that people sometimes use motor oil for that purpose, but I'm not sure of the results with that.

 

I'm going to second Mabuse. In most cases I'd say yes. I've done things like this to stabilize mixes that in theory have serious degradation issues based on aqueous reactions in the small amount of water supplied by the atmosphere. For example. Ammonium perchlorate and magnalium WITHOUT any dichromate or other treatment, and also, Ammonium perchlorate and Potassium nitrate and other nitrates.

 

In the cases I've had success (which I declared after more than a year exposed to to the atmosphere and no serious degradation) I have been using the benefits of OCD about keeping water out. I dried everything in the oven, even the MgAl and tools used to process it, things that you don't typically consider to be water sources, and then sealed it up with wax, oil or some other water resistant binder ASAP, before anything has fully cooled.

 

One of my abundant "on hold" projects (due to me making more plans than I have time for by an order of magnitude) is to mill up some Sodium nitrate and Sodium benzoate, add 5-10% MgAl, and enough wax to keep it dry. Tuned to burn to Carbon monoxide I recon it would be a really good work horse core burning model rocket motor. Cheap, reasonably powerful, and with that yellow, yellow, bright flame. It should look more impressive than it really is

[schroedinger]

If you wan`t to use this bags of desiccants you would need to regenerate them or buy new ones (they aren't were cheap).

 

For storing you would need to put your things into an airtight container together with the dessicant (CaCl2 would be the best as it is cheap, and pH neutral). Sodium Nitrate is really higroscopic so your first problem would be making Bp at all. If you trow it into your mill, it starts absorbing there for a couple hours, if your mill is airtight this won`t be to much. Next your granulating you Bp with Denaturated alcohol or aceton, both are technical grade, and still contain Water, probably around 5%. These stay inside your Composition, ruining it. So you would need to use Dryed solvents (should be ok if you dry em over CaCl2 for a night). Next stepp wouldbe srying you`re comp in a Water free Dryer, there a just two options to do that 1: Drying in a vacuum chamber 2: drying in a chamber witch got every hole going in and out sealed with a desiccant in a tube.

 

And still after this you would probably introduce so much water that your comp is still burning very slow and after maybe a half year of storage with the desiccant is absorbed enough moisture to fail

[Carbon796]

If you wan`t to use this bags of desiccants you would need to regenerate them or buy new ones (they aren't were cheap).

 

For storing you would need to put your things into an airtight container together with the dessicant (CaCl2 would be the best as it is cheap, and pH neutral). Sodium Nitrate is really higroscopic so your first problem would be making Bp at all. If you trow it into your mill, it starts absorbing there for a couple hours, if your mill is airtight this won`t be to much. Next your granulating you Bp with Denaturated alcohol or aceton, both are technical grade, and still contain Water, probably around 5%. These stay inside your Composition, ruining it. So you would need to use Dryed solvents (should be ok if you dry em over CaCl2 for a night). Next stepp wouldbe srying you`re comp in a Water free Dryer, there a just two options to do that 1: Drying in a vacuum chamber 2: drying in a chamber witch got every hole going in and out sealed with a desiccant in a tube.

 

And still after this you would probably introduce so much water that your comp is still burning very slow and after maybe a half year of storage with the desiccant is absorbed enough moisture to fail

 

That's a lot of effort and expense that's not really necessary. Unless the area where you live has a HIGH, relative humidity average. Like 70% or above. I think most people just repeat the same stigma that they always hear about sodium nitrate. Rather than any results from actual use. I water bind sodium nitrate, yellow and orange stars with SGRS all the time. They are left out to air dry, then stored in air tight containers or freezer zip lock bags with no desiccant.

[schroedinger]

Nope won`t say ii never had sodium nitratein Hand. And yes i won`t recommend using it in this way, as it is hygroscopic (no comparision to things like LiCl or ammonia nitrate), but if you look at the hummidity over sodium nitrate, it is quite a stroabsorbent. But if you can bin`d em also with water, then it`s probably fine,stillwould recommend to use other solvent

[Seymour]

Where I live has a high relative humidity obviously. I certainly couldn't get away with using water on Sodium nitrate stars. Colorado must be pretty dry.

 

It really depends on the quality of the nitrate, your humidity, and what you seek to make. I've made useable stars with agricultural grade NaNO3, though they definitely did perform a bit sluggishly.

 

However for rockets you really noise the loss of power from sluggish burning. I've used Analytical Reagent grade NaNO3 in the first test of my nitrate-benz fuel. It still got wet and burned shit just from the air.

 

It's great that you can use it successfully, Carbon. I also agree that a lot of people copy other statements without any real experience, and facts sometimes change or are exaggerated .

 

Still, I assure you that it's true that NaNO3 can be a hygroscopic nightmare in the right conditions (that many of us are stuck in).

[Carbon796]

Seymour, your also kind of fighting two evil's, because the sodium benzoate will also take up water in high humidity.

[Seymour]

For sure, it's not the best mix from a moisture perspective. Sodium nitrate and sucrose was actually the worst I've ever encountered, again, no surprise.

 

However I've been unable to make even Sodium nitrate, Red Gum and MgAl based stars with water and have them fully dry. However this is where I live. My experience shows that Sodium nitrate comes with a host of hygroscopic problems.

 

I am fully aware that people in many other parts of the world use it without any serious issue. There is no surprise that shown on a map, people like me tend to live in humid areas. You mentioned 70% as a humidity above which problems may exist with hygroscopicity.

 

Where I live, humidity as low as 70% is very dry. Perhaps not unheard of, but somewhat exceptional. I take it that where you live, 70% is getting towards the more humid end of the spectrum.

[Jonathan]

Glad to have found this thread. I like NaNO3, which comes to me as prills, which I grind down as needed and store in airtight containers with dessicant bags. No problem with moisture.

 

NaNO3 works as flash when mixed stoichiometrically with Mg (especially) or Al. It acts as a very good oxidizer for Zn. B.P. made with NaNO3 works just about as well as regular B.P., in my experience.