Making Magnesium

[ANFO]

I've been wanting to make some ammonium nitrate based composite rockets, and the standard basic one is a 60/40 ratio of ammonium nitrate to magnesium. This of course requires a fair amount of magnesium, so I tried to find a way to source/produce larger amounts of cheaper magnesium powder.

 

Then it occurred to me that one can make metals through electrolysis. After a bit of investigation I found that it is a fairly common method of producing magnesium.

 

The basics are: Melt magnesium-chloride, and then perform basic electrolysis (which gives the Mg+ ion an extra electron turning it into solid magnesium, and producing chlorine gas).

 

The aim is of course to do this at maximum yield/ minimum cost. A few good points to start with is that magnesium carbonate can be purchased by the kilogram from pottery suppliers. It can be converted into magnesium chloride through a simple neutralization reaction with hydrochloric acid (pool acid).

 

The problems are magnesium-chloride melts at +- 700 degrees centigrade. Its not impossible to achieve that temperature but to do it in some kind of electrolysis apparatus could pose some problems. I was thinking ceramic pot and propane. Another problem along that line is that magnesium melts at 650 degrees, so it will produce a liquid.

 

As far as electrodes go, I'm not completely sure. Would graphite work or will the chlorine gas damage them too quickly? And of course there's the problem of copious amounts of chlorine gas being produced.

 

Any thoughts on this? I will definitely be trying it out to see how cost and effort effective it is

Edited August 28, 2012 by ANFO

[WSM]

I've been wanting to make some ammonium nitrate based composite rockets, and the standard basic one is a 60/40 ratio of ammonium nitrate to magnesium. This of course requires a fair amount of magnesium, so I tried to find a way to source/produce larger amounts of cheaper magnesium powder.

Then it occurred to me that one can make metals through electrolysis. After a bit of investigation I found that it is a fairly common method of producing magnesium.

The basics are: Melt magnesium-chloride, and then perform basic electrolysis (which gives the Mg+ ion an extra electron turning it into solid magnesium, and producing chlorine gas).

The aim is of course to do this at maximum yield/ minimum cost. A few good points to start with is that magnesium carbonate can be purchased by the kilogram from pottery suppliers. It can be converted into magnesium chloride through a simple neutralization reaction with hydrochloric acid (pool acid).

The problems are magnesium-chloride melts at +- 700 degrees centigrade. Its not impossible to achieve that temperature but to do it in some kind of electrolysis apparatus could pose some problems. I was thinking ceramic pot and propane. Another problem along that line is that magnesium melts at 650 degrees, so it will produce a liquid.

As far as electrodes go, I'm not completely sure. Would graphite work or will the chlorine gas damage them too quickly? And of course there's the problem of copious amounts of chlorine gas being produced.

Any thoughts on this? I will definitely be trying it out to see how cost and effort effective it is

 

It seems to me the best way to get fine magnesium is to buy it. Barring that, one could make magnalium (magnesium aluminum alloy) and try that. If magnalium doesn't work, one could digest the aluminum out of it with an alkalai and be left with finely divided magnesium (all this to be proven by experimentation, of course).

 

Good luck and let us know how it goes.

 

WSM

Edited August 29, 2012 by WSM

[Dean411]

Just to make sure oyu made a typo it's not Ammonium Nitrate it is Perchlorate.

[WSM]

Just to make sure oyu made a typo it's not Ammonium Nitrate it is Perchlorate.

 

Actually, he's right; it's ammonium nitrate and magnesium (not AP). I've heard of this and it's documented to work. Just to be on the safe side, when you mill the ammonium nitrate to make this rocket propellant, add some zinc oxide to the AN. I'm guessing (I really don't know for sure) it's about 5-10% ZnO to the AN to help prevent problems with crystal phase changes in the oxidizer. Plus, without the high energy output of the magnesium, the AN doesn't have the energy to produce the correct amount of thrust for proper performance of the engine.

 

This sounds like a challenging project.

 

Good luck and tell us about it.

 

WSM

[THEONE]

I also trying to make an AN based rocket propellant... maybe we can help each other. Magnaliun is as good as Mg for this work, but i really want to make a non metalized based AN propellant for economical reasons. Somewhere i read that AN and sorbitol can be burned... cause of alcohol based sugar... i would try it but i do not have here any source of sorbitol

 

P.S. Here is a page for two good AN based propellants

Edited September 2, 2012 by THEONE

[WSM]

I also trying to make an AN based rocket propellant... maybe we can help each other. Magnaliun is as good as Mg for this work, but i really want to make a non metalized based AN propellant for economical reasons. Somewhere i read that AN and sorbitol can be burned... cause of alcohol based sugar... i would try it but i do not have here any source of sorbitol

 

If you can source sorbitol, give it a try. I doubt it will perform nearly as well, but my doubts shouldn't stop you from trying. One serious problem with AN is it's hygroscopic nature, and this will most likely cause trouble (the darned stuff turns to soup from atmospheric moisture). If you can seal it somehow, you have a fighting chance for success. Let us know what you are able to achieve.

 

I've seen great performance of potassium nitrate and sorbitol fuel grains, but I suspect problems with AN and sorbitol grains.

 

WSM

[THEONE]

WSM I would try it but i have not any source of sorbitol

 

According to Guipep an AN/Sorbitol 85/15 ratio has a Isp of 219... Not bad

 

If you have already prepare the motor with anhydrous AN, just an air tide plug at the nozzle throat will be enough to remain the AN dry

 

P.S. I have read somewhere that ammonium dichromate is the best catalyst for AN but i have never try it.

I have found that a very good catalyst for AN is Cuo

Take a look on this file

Edited September 2, 2012 by THEONE

[WSM]

WSM I would try it but i have not any source of sorbitol

According to Guipep an AN/Sorbitol 85/15 ratio has a Isp of 219... Not bad

If you have already prepare the motor with anhydrous AN, just an air tide plug at the nozzle throat will be enough to remain the AN dry

P.S. I have read somewhere that ammonium dichromate is the best catalyst for AN but i have never try it.

I have found that a very good catalyst for AN is Cuo

Take a look on this file

 

One source of sorbitol is health food or pharmaseutical suppliers, since sorbitol is a simple sugar as opposed to sucrose.

 

Thanks for the link, I added it to my composite rocket files. That link, by the way, does mention ammonium dichromate as a catalyst for AN. I'm told black copper oxide and green chromic oxide (both available from ceramics suppliers in the US), ball-milled for an extended time make an excellent catalyst (perhaps worth trying).

 

I suspect anhydrous AN would be "thirstier" than simply milled AN, plus I have concerns about most sealing systems that don't involve hermetic sealing with a desicant in place before sealing. I suppose I've had too many problems with hygroscopic materials in a humid environment.

 

WSM

Edited September 2, 2012 by WSM

[THEONE]

Making AN phase stabilized with Zno it says that is also reduce the hygroscopic nature of AN, but i have never try it

[Arthur]

Manufacture by electrolysis liberates HUGE amounts of chlorine which is a war gas, probably banned under the Geneva convention, and certainly very offensive to man, animals ans plants. If Mg is denser than the salt that you use you should be able to pour the salt in at the top and get metal out at he bottom. Remember that magnesium will ignite easily so hot liquid magnesium may need nitrogen or argon atmosphere until it's cold.

[mikeee]

Sorbitol is available on Ebay as a last choice. (I might have seen this in Walmart under a trade name)

Look in the sweetner isle and look at the ingredients.

You could also use Eryithritol for solid rocket fuel grains.

There is a rocket hobbiest using Erythritol to put a rocket into orbit.

He is located in Iowa has a pretty cool website.

I can look it up if you are interested, you should have no problem finding with google search.

 

Mikeee

[WSM]

Manufacture by electrolysis liberates HUGE amounts of chlorine which is a war gas, probably banned under the Geneva convention, and certainly very offensive to man, animals ans plants. If Mg is denser than the salt that you use you should be able to pour the salt in at the top and get metal out at he bottom. Remember that magnesium will ignite easily so hot liquid magnesium may need nitrogen or argon atmosphere until it's cold.

 

Given that choice, make it Argon for sure. Magnesium nitride reacts with moisture, and not in a good way.

 

WSM