Sciencemadness Discussion Board

Most Powerful Rocket Fuel Catalyst?

APO - 18-4-2013 at 21:38

I have heard of Red Iron Oxide, Black Copper Oxide, Copper Chromite, and Phenolphthalein, can I get any indication on the power increase and/or other catalysts?

Bert - 18-4-2013 at 21:48

That might depend on the oxidizer and fuel. Specify?

APO - 18-4-2013 at 22:30

Specifically for Nitrates, Chlorates and Perchlorates. Fuel is not carved in stone yet.

Ral123 - 18-4-2013 at 23:15

What do catalyst do in rocket fuel? I dream of a fuel with steady burn speed, no matter how dump I made the engine.

KonkreteRocketry - 19-4-2013 at 01:28

Just increase the burning surface area, why bother using catalyst.

Fantasma4500 - 19-4-2013 at 14:33

well copper oxychloride is good for whistle mix i know..
pressure increases as much as..... 10 times i think compared to with / without copper oxychloride..?

potentially MnO2 should work
for thermite MnO2 is stronger than CuO
if we say we can see the catalysing properties of a metal oxide by making a thermite with it MnO2 would be the best, but thats not sure at all..
just as kno3 is better for synth. etn it might be worse for other synthesis, so very likely is very different from composition to composition, perhaps even amounts will matter, as in more fuel than oxidizer ratio another catalyst will be better

Xenoid - 19-4-2013 at 17:59

Richard Nakka has a short discussion of burn-rate catalysts on his website here;
http://www.nakka-rocketry.net/burnrate.html

1% red ferric oxide is a standard catalyst added to KNO3 "candy type" propellents (KNO3 with Sucrose, Sorbitol, Xylitol, Erythritol, etc.). Ferrocene would appear to be an excellent catalyst, judging from the graph on his page.

A few years ago I experimented with several possible catalysts, in an attempt to obtain smoother and faster burn-rates in KNO3/ Erythritol propellent.

These include the oxides of Fe (red & black), Cu (red & black), Cr, V, Co, Ni, Ti and Mn along with finely powdered charcoal, sulphur, copper and aluminium - all at the 1% by weight level. The oxides were from a pottery supply shop.

Of these, the only additives to make any measurable difference were red Fe2O3, V2O5 and powdered charcoal. The melted propellent turned grey with the addition of the V2O5, this may have been due to catalysing the breakdown of the Erythritol to produce a fine distribution of free carbon in the melt.

Nakka mentions the use of potassium dichromate catalyst in AN based and KN/sugar propellents. I tried this catalyst in a 60:40 KNO3/Erythritol mix, when melted the orange coloured mix turned green and then IGNITED. This was at a temperature of <130 oC. !!! Do not use this in "candy type" propellents. EDIT: Looking back at my notes, I see I did not accurately measure 1%, and may have used slightly more. Even so, I would not trust this chemical in association with "candy-type" melted propellents!


[Edited on 20-4-2013 by Xenoid]

APO - 19-4-2013 at 18:45

How would I increase burning surface area?

Xenoid - 19-4-2013 at 18:59

Quote: Originally posted by APO  
How would I increase burning surface area?


Hmmm.... If you don't know that, then you should not be messing around with rocketry!

Use a cored propellent grain, increase the diameter of the core, use a different core geometry, use an unbonded grain - probably covers most of the possibilities!

KonkreteRocketry - 20-4-2013 at 00:11

Quote: Originally posted by Xenoid  
Quote: Originally posted by APO  
How would I increase burning surface area?


Hmmm.... If you don't know that, then you should not be messing around with rocketry!

Use a cored propellent grain, increase the diameter of the core, use a different core geometry, use an unbonded grain - probably covers most of the possibilities!


lol, well everyone starts off noob.

APO you know its best when you make propellant into grains, with cylinder hole in the center, which is where you shall ignite from.

http://www.nakka-rocketry.net/th_grain.html

Fantasma4500 - 20-4-2013 at 01:48

Quote: Originally posted by APO  
How would I increase burning surface area?


you press the fule with a cone of some sort, or a stick so theres a hole in the center
IIRC this is called the ''soul'' of a rocket

APO - 20-4-2013 at 22:41

Thank you, never thought of anything besides normal grains, but can we get back to catalysts?

KonkreteRocketry - 20-4-2013 at 22:48

Quote: Originally posted by APO  
Thank you, never thought of anything besides normal grains, but can we get back to catalysts?


I only tried CuO and Fe2O3

CuO has a blue greenish flame, but does not speed it reaction up too much, and Fe2O3 increase the speed a lot.

APO - 21-4-2013 at 10:35

I heard of pure Phenolphthalein as a catalyst, I have 60g of the stuff, I saw it here : https://www.youtube.com/watch?v=NNlIvGN8SWw I personally observed that it had more complete combustion, rather than faster combustion.