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RP-1 is highly refined kerosene. If I bought a supply of commercial-grade kerosene, by what process could I convert it to RP-1, And, while I'm at it, do I have any good choices for non-cryogenic oxidizer to use with it, other than the highly-unstable High Test Peroxide (HTP)?

Oh, and in case anyone is seriously considering doing such things, I add the following caveat, from Asimov's foreword to the book Mark Adler cites:

Now it is clear that anyone working with rocket fuels is outstandingly mad. I don’t mean garden-variety crazy or a merely raving lunatic. I mean a record-shattering exponent of far-out insanity.

There are, after all, some chemicals that explode shatteringly, some that flame ravenously, some that corrode hellishly, some that poison sneakily, and some that stink stenchily. As far as I know, though, only liquid rocket fuels have all these delightful properties combined into one delectable whole.

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    $\begingroup$ These links may help answer this question: [1] [2] $\endgroup$
    – called2voyage ♦
    Commented Feb 25, 2014 at 15:37
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    $\begingroup$ Before you mess around with rocket fuel, I highly recommend that you READ THIS BOOK. Your life may depend on it. $\endgroup$
    – Mark Adler
    Commented Feb 25, 2014 at 18:16
  • $\begingroup$ @MarkAdler: Indeed! This is so relevant I should add a quote as a caveat. $\endgroup$
    – Jerard Puckett
    Commented Feb 25, 2014 at 18:27
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    $\begingroup$ This question looks like a good way to get onto a government watch list... $\endgroup$
    – Tristan
    Commented Apr 28, 2014 at 14:39
  • $\begingroup$ What kind of rocket do you plan to create? Because stratospheric rockets, like these used in meteorology, use much safer and easier to create fuels. $\endgroup$
    – SF.
    Commented Apr 29, 2014 at 11:09

3 Answers 3

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You're not going to significantly improve on your commercial kerosene. The process of fractional distillation used means that they've already cooked off and catalyzed away most of the undesired materials. "Low grade" now generally means "devoid of higher energy chains" not "mixed low and high energy chains," as it's the leftovers when they distilled out the higher grade already, rather than being undifferentiated kerosene. The higher grades command significant prices, and so it's worth it to the refinery to extract them, then sell the lower grade leftovers. Even then, they've highly processed them already.

A look at how Kerosene is refined: http://www.madehow.com/Volume-7/Kerosene.html

And a discussion of what is in oil: http://www.setlaboratories.com/overview/tabid/81/Default.aspx

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    $\begingroup$ I concur, it would be a bit like trying to make butter out of skimmed milk. $\endgroup$
    – TildalWave
    Commented Feb 26, 2014 at 2:58
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    $\begingroup$ That's a pretty good analogy, @TildalWave. $\endgroup$
    – KeithS
    Commented Feb 26, 2014 at 19:40
  • $\begingroup$ If "low grade" actually was mixed low and high energy chains, would that not imply uneven burning? Especially in a rocket, that's something you do not want, but even in other situations it would be undesirable... $\endgroup$
    – user
    Commented Apr 1, 2016 at 21:34
  • $\begingroup$ @MichaelKjörling: For a very long time kerosene was used to fuel lamps and stove burners. In both applications the users would not notice uneven burning considering wood was also considered acceptable fuel for the same purpose (and still is!) $\endgroup$
    – slebetman
    Commented Mar 2, 2017 at 2:52
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    $\begingroup$ @MichaelKjörling no, the mixed chain lengths didn't really make for uneven - they're all the same specific gravity and density, and only very tiny differences in non-combustion chemistry, and intermix pretty thoroughly. The longer chains carry more energy per unit mass and volume; they get removed by fractional distilation, to make JP8. Old school kerosene was more energetic than modern kerosene, and less energetic than JP8, because old school kerosene was a few percent JP8... and modern isn't. $\endgroup$
    – aramis
    Commented Mar 8, 2017 at 7:05
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What is your objective? For many purposes, any hydrocarbon will suffice. Gasoline and diesel are quite available. RP-1 has longer chains, which means more carbon per hydrogen and a higher boiling point. For an oxidizer, nitric acid might be the storable oxidizer of choice. If you need a certain level of performance, you have a larger problrem.

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    $\begingroup$ I was going to suggest nitric acid; despite some inherent hazards in handling the stuff, and a short shelf-life in "fuming" superconcentrated form, it's an article of commerce and readily available in relatively large quantities. However, it has a lot of interest in "energetic materials" chemistry, aka explosives and rocket fuel, so I would imagine a large shipment of WFNA to a residential address would attract the BATFE's attention. $\endgroup$
    – KeithS
    Commented Feb 26, 2014 at 19:44
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    $\begingroup$ If you're not too concerned with performance and, consider that the Redstone launcher that flew the first two Mercury suborbital flights burned 75%/25% ethyl alcohol/water with LOX with a specific impulse of 215 seconds. Such fuel is readily available in small quantities at most liquor stores: en.wikipedia.org/wiki/Bacardi_151 $\endgroup$
    – Russell Borogove
    Commented Dec 2, 2015 at 3:05
  • $\begingroup$ @RussellBorogove: Fuel is not a problem. Another approach is to use commercial propane. You can use the boiling to eliminate impurities. Oxidizers are the the problem and LOX, though very high performance and available, is hard to handle. $\endgroup$
    – Ross Millikan
    Commented Dec 2, 2015 at 3:21
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From John D. Clark's Ignition! (from Mark Adler's link in second comment under question), the section on the specifications for RP-1 (pp 104-105), you could improve your kerosene by reducing the olefin content to less than 1% and the aromatics to less than 5%. From called2voyage's second cite, treat it by acid washing and sulphur dioxide extraction. You've not improved the hydrocarbon ratio, but at least you'll have far less tar & soot gumming up the works.

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