H2O2 BP

[krimmie]

The other day I had a dream that I mixed up some meal powder(75% KNO3,15% C,10% S) to make fuses in a hurry. I add boiling water and a little dextrin to make the fuse slurry. Anyway, I had some leftover meal powder and decided to add a few drops of 6% H2O2 to it. After this dried out I lit some with a match and it burned extremely fast! It burned more rapidly than my finished BP! Has anyone else tried this?

<small>[ May 25, 2002, 06:20 AM: Message edited by: krimmie ]</small>

[HOOPS123]

Maybe it had the same effect as corning the meal powder.

[vulture]

The hydrogenperoxide produced alot of O2, this is why it burned so fast.... :rolleyes:

I don't think the mods will appreciate this kind of post....
(why do you say that?)

<small>[ May 25, 2002, 10:59 AM: Message edited by: PYRO500 ]</small>

[PYRO500]

what I think happened was that the H2O2 was decomposed beacuse of some of the stuff in the powder that is why it foamed, why it burned faster is not easy for me to say, have you tried two identical samples of the BP and added water to one and H2O2 6% to the other? it is possible that the dextrin may have slowed the burning by not giving as much surface area.

[krimmie]

-have you tried two identical samples of the BP and added water to one and H2O2 6% to the other?

Pyro, I am in the process of doing this now. The dextrin was added to the mix for making the fuses only, I didn't put any in with the meal powder and H2O2.

Here is a picture of the finished product...it looks and feels like lava rock. It does indeed burn faster than my homemade BP, but my homemade BP obviously sucks!

<a href="http://www.boomspeed.com/krimmie/H2O2-BP.JPG" target="_blank">http://www.boomspeed.com/krimmie/H2O2-BP.JPG</a>

<small>[ May 25, 2002, 03:55 PM: Message edited by: krimmie ]</small>

[BrAiNFeVeR]

What's the green stuff in your BP ??

As I (and thus everybody)can still see the crystals of (probably) KNO3, this is not even close to good BP !!!

The oxidiser must be finely dispersed between the fuels, so that you get a homogenous mix.
Some site's say to even make the KNO3 recrystalise in the charchoal by applying pressure to the mix when drying ....

[krimmie]

Read original post again. This is meal powder with H2O2...I was just comparing the burn rate with my homemade BP.

[kingspaz]

krimmie, this is what i think happened:
1. H2O2 soaked into charcoal in the BP.
2. some H2O2 decomposed resulting in the release of O2.
3. charcoal being porous contained some of the O2 formed.
4. when ignited the O2 in the charcoal aided combustion significantly.

[krimmie]

Thanks kingspaz, that makes sense to me! It doesn't replace BP but it is a marked improvement over meal powder for simple fountains and the like. Appreciate the feedback.

[Anthony]

I'd be surprised if the same increase in performance couldn't be obtained by replacing the H2O2 with H2O. Wetting and drying BP, often with alcohol is a long used method of increasing performance, which I personally think is caused by recrystalising the KNO3.

[Arkangel]

A well documented method of manufacturing BP suggests that the burn rate can be massively increased by mixing the slurry described, and then boiling it to dissolve the saltpetre (which is 30 or so times more soluble at 100 C than at 10 degrees C, the boiling point is also elevated to 115 degrees, allowing even more to be dissolved).

The mixture is then removed from the heat and then has the alcohol dumped into it, causing it to boil vigorously. The theory is that the saltpetre, which was in solution (and permeates the charcoal) rapidly cools, depositing very fine crystals.

I'm curious what your mixture did when you added the peroxide, maybe it caused it to ccol and precipitate like this, giving you a better mix? Maybe as has been suggested, Oxygen was deposited in it instead, to me that seems unlikely though.

[kingspaz]

the only explinations i can see are the unlikely one above i offered or as a few of you have said. that is the KNO3 recrystalised. i'd like to add that the burnrate is improved by this because the charcoal being porous allows the KNO3 to crystalise inside it. i think...

[inferno]

The H2O2 would have decomposed in the mix, to either H2+O2 or maybe H2O+O2 - the H2O would have evaporated off and left the O2, which would have been dissolved maybe in the H2O somehow? then recrystallised in the charcoal, the same as the sulphur, making the charcoal pores filled with sulphur and KNO3, as well as the O2 or whatever from the peroxide.

Otherwise some H2O2 may have residued in the charcoal pores, adding even more oxygen. And finally, using alcohol to mix your BP helps a lot more than water, maybe the H2O2 is working like an alcohol, or just helps to make BP

[Arkangel]

According to the "CIA method" for BP, you specifically NEED boiling water to dissolve the KNO3, which as folks are describing, premeates the charcoal, along with the sulphur. The alcohol causes rapid cooling of the solution (rather than just making a mix with alcohol as the solvent), and because KNO3 cannot remain in solution in concentration at low temperature, it precipitates where it is - inside the charcoal particles, as very small crystals. That's the principle behind good bp - very close association between the chems. (Experts also recommend a couple of sessions of ball milling as well - if anyone wants me to post the actual method, let me know)

And that's what I think may be happening, the decomposition of the H2O2 accelerates precipitation, that's all.

<small>[ May 28, 2002, 08:11 AM: Message edited by: Arkangel ]</small>

[vulture]

How would the decomposition of H2O2 accelerate precipitation knowing that it is an exothermic reaction? And the H2O2 surely decomposes when it contacts the BP, the KNO3 acts as a catalyst.

[Arkangel]

Well I could of course be wrong, it's certainly happened before, but I wasn't considering the H2O2 reacting with the KNO3, I assumed that the heat of the solution made it decompose by evaporation, an endothermic reaction.

What you suggest makes sense though, so I'll shut up for now.

By the way, the "expert" I was referring to was Tom Perigrin etc, I wasn't inferring that it was me, I'm a baby in this area. <img border="0" title="" alt="[Wink]" src="wink.gif" /> Having just read his introductory pyro book, I was struck by how important it is to precipitate the KNO3/S solution inside the charcoal.