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Is it possible for me to buy kerosene from a local store and then try to refine it to the extent where it would be considered RP1. If so how would I do it? For those who are wondering me and a group of friends is trying to make a model rocket with an actual engine(aka not store bought), but want to learn about the burning process first. In addition, what is the best oxidizer? We think liquid hydrogen is the best.

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closed as off-topic by Machavity, Jack, Mark Omo, uhoh, Nathan Tuggy Jul 18 '18 at 2:22

This question appears to be off-topic. The users who voted to close gave this specific reason:

  • "This question relates to an amateur experiment of extreme danger. This community does not condone such experiments as there may be risk to your health (or even risk of death), and they may even be illegal in your jurisdiction. If you are considering making your own rocket propellant/fuel, please DO NOT DO THIS! Please see the help center." – Machavity, Jack, Mark Omo, uhoh, Nathan Tuggy
If this question can be reworded to fit the rules in the help center, please edit the question.

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    $\begingroup$ Liquid hydrogen makes a very poor oxidizer. Because it is a fuel. $\endgroup$ – Organic Marble Jul 8 '17 at 22:53
  • $\begingroup$ Run away. Fast. Your rocket is going to go boom, not fly. $\endgroup$ – Loren Pechtel Jul 8 '17 at 23:53
  • $\begingroup$ well then why do NASA and others your LH2? $\endgroup$ – jack Jul 9 '17 at 3:01
  • $\begingroup$ @jack LH2 is a very very efficient Fuel* It was used by NASA for quite a few rockets. But a rocket fuel must be combined with an oxidizer* to burn, such as oxygen. Thus Liquid Oxygen and Liquid Hydrogen make for a very efficient (yet pain in the butt) fuel. $\endgroup$ – Jake Blocker Jul 9 '17 at 4:47
  • $\begingroup$ @JakeBlocker OHHH ok thank you now i understand $\endgroup$ – jack Jul 9 '17 at 8:20
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I'm going to start off with a warning: if you want to get started with model rocketry, it is about a thousand times safer and easier to start with off-the-shelf solid rockets. Don't even consider trying to build your own liquid fueled engine until you've learned a lot more.

That said, reaching the RP-1 specification from commercial kerosene is probably beyond what a novice chemist can reasonably attempt at home, but for simple liquid rocket engines you don't need RP-1.

Normal kerosene is problematic in regeneratively cooled engines (which pass the fuel through channels around the combustion chamber to remove heat) because some of the components vaporize at relatively low temperatures, while others polymerize; the deposits and gas bubbles so produced impair heat transfer, leading to overheating of the chamber walls, burn-through, and rapid failure.

It's much simpler to build a non-regeneratively cooled engine, which requires much lower combustion temperature; the ugly way to achieve this is to run the engine very fuel-rich, leaving much of the fuel uncombusted, which gives you a very sooty (and somewhat hazardous) exhaust. The better way is to use a different fuel entirely: the V-2 and Redstone rockets used 75% ethyl alcohol, 25% water, which is available from several sources -- perhaps most amusingly (if not the cheapest or purest) your local liquor store (e.g. Bacardi 151 or Everclear).

As Organic Marble alludes, the oxidizer of choice is liquid oxygen rather than hydrogen. This is also tricky stuff to handle; nearly anything you spill it on will become highly flammable if you're lucky and explosive if you're not.

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  • $\begingroup$ So maybe start with 75% ethyl alcohol, 25% water, and gain experience and then move up to higher difficulty chemicals? $\endgroup$ – jack Jul 9 '17 at 3:00
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    $\begingroup$ Or, y'know, read the first paragraph again. $\endgroup$ – Russell Borogove Jul 9 '17 at 4:08
  • $\begingroup$ hey a man can dream ya know $\endgroup$ – jack Jul 9 '17 at 8:19
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    $\begingroup$ @jack I understand wanting to jump straight to the higher end but there really is a high risk associated with mistakes made making any rockets. If you want to make your own you can start with some solid rockets, make sure you're fully aware of the dangers involved before starting though. $\endgroup$ – Lio Elbammalf Jul 9 '17 at 14:22
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    $\begingroup$ If your dreams abandon you, at least you could drink the alcohol $\endgroup$ – Gustav Jul 11 '17 at 14:10

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