Is the mixture KNO3 + sugar explosive???
Henk Jan Meuleman
can be explosive. Does anyone know in
what ratio this mixture is explosive?
Thanks!
Bas
Bas from Holland!
"Henk Jan Meuleman" <meul...@zonnet.nl> wrote in message
news:f0Z_7.59452$sl6.153424@zonnet-reader-1...
Captain Beefheart
sugar makes a fairly low-specific-impulse rocket fuel. Actually, it's the
sugar that melts and becomes the fuel component. I don't believe the KNO3
goes into solution very well in molten sugar. It winds up acting as the
oxidizer that's intimately (and hopefully, evenly) dispersed throughout the
sugar once it cools and hardens. The KNO3 needs to be in relatively fine
powder form before it's added to the molten sugar, so it won't wind up
providing oxidizer-rich pockets within the hardened sugar mass.
For fairly obvious reasons, this stuff is referred to as "cotton candy".
KNO3/sugar is something that model rocketeers used (among other things) in
the old days, before the advent of factory-made engines. It's about the
"lowest powered" material that one could put in a rocket and expect to get
some thrust out of. Metal powder/perclorate/asphalt is a lot more efficient
as a solid rocket propellant, albeit less stable and far more dangerous for
at-home compounding. Many modern SRB systems use this latter composition, or
modified versions of it.
Adding a finely-powdered reactive metal to the "cotton candy's" mix, such as
aluminum or magnesium in the proper proportions, will significantly improve
its specific thrust. However, it does so at the expense of requiring the
motor to have a better casing to handle the increased temp/pressure, as well
as requiring a nozzle that's made of a more ablation-resistant material than
you might use for simple KNO3/sugar mixes. (Added Al or Mg dust also
provides the rocket with a spectacularly bright exhaust plume and beautiful
white exhaust trails due to the additional reaction of the metal with the
oxygen in the KNO3.)
I don't believe that you could confine this stuff well enough to have it
detonate in the same manner that a high explosive would under similar
circumstances. It will certainly burst an inadequately-designed motor tube
but that's not really classified as a detonation. I do recall reading about
some of the old-time basement bombers inadvertently setting off an engine
they'd just poured/cast into a motor tube, as they were screwing in the
exhaust nozzle. This was due to their allowing some of the molten mixture to
get into the threads of where the nozzle screwed into the motor body.
Once the nozzle threads grind into the fuel spillage on the motor tube
threads, they'll crush it and may provide adequate heat from the friction to
light it off. At that point. it's ...pfft...WHOOSH! Without any warning,
you get hit in the face by the 6000 deg main exhaust plume of the main
charge and perhaps the nozzle if it wasn't screwed in very far before it set
off the main charge.
There have been a few similar accidents that have happened in munitions
plants. Friction-sensitive explosives (such as picrate-based compounds)
wound up getting onto the threads of the ports of mortar or artillery
shells, where they're filled by glugging in pourable explosives. I think the
Japanese had some problems with this late in WW2, when a lot of their
munitions were being made by conscripted grade-school kids, under emergency
conditions, in bombed-out factories.
So, please be careful if you feel that you must play with any of this stuff.
I don't recommend anyone do it but I suppose that cooking up some "cotton
candy" is safer than trying to make high explosives in the bathroom.
Geoff
"Henk Jan Meuleman" <meul...@zonnet.nl> wrote in message
news:f0Z_7.59452$sl6.153424@zonnet-reader-1...
Don Thompson
won't even try to list them all. Where in hell did you get your out of
date/wrong information?
--
Don Thompson
Another Thompson Scion
"Captain Beefheart" <capt_be...@hotmail.com> wrote in message
news:X6b%7.6168$3x.2083838068@newssvr30.news.prodigy.com...
Terry King
5 years from now:
flas...@ix.netcom.comghost says...
> There are numerous inaccuracies in your post. So many, in fact, that I
> won't even try to list them all. Where in hell did you get your out of
> date/wrong information?
Please list the 2 or 3 you think are most dangerous assumptions.
> > When you melt them together (very cautiously, in a double boiler), KNO3
> and sugar makes a fairly low-specific-impulse rocket fuel.
Yes, this is well known. Made many of them. In the 60's I saw a graph
that purported to be the pressure / burning rate relationship of KNO3-
sugar. It was supposedly fairly linear to 3000PSI or more, hopefully
showing that the material was 'relatively safe' for amateur rocketry.
The anecdotal information I recall was that this was true.
I have no 'good' data on this subject. If anone does, please let's leave
it here for future readers.
Captain Beefheart
"Rocket Propellant Handbook" by Boris Kit and Douglas Evred. Copyright 1960
by MacMillan and Co. (yes, that's 1960)
as well as some recollections from reading elsewhere that I did more years
ago than I care to remember. As the say, the memory is the second thing to
go...
Plus, I tried making some KNO3/sugar goop in the early 1970's and got
nowhere with it, other than creating a big mess in a double-boiler. I
suppose that doesn't exactly count as "extensive background" on the subject,
but I never claimed that the information I had was up-to-date nor do I make
any claims to be a chemist or propulsion engineer. I apologize if I write in
such a was as though to imply that I'm anything other than a than a
dilettante in the field of propellants and explosives.
I'm an EE by education, not a trained chemist (although I had some chem
classes in college, eons ago...again, doesn't exactly make me an authority).
I take it you're either a propellant/explosives chemist or work in a related
profession? As one engineer to another, I would appreciate it very much if
you'd correct whatever I said that was inaccurate or was wrong about the
topics below.
This newsgroup is so chock-full of postings from teeniebombers, schoolyard
assassin wannabes and fringe science loonies that it'd be refreshing to have
an intelligent exchange of information with individuals who actually work
with or design explosive components for a living (such as Jerry Hurst, when
he posted to this group years ago).
Geoff
"Don Thompson" <flas...@ix.netcom.comghost> wrote in message
news:a1jq1r$4fc$1...@slb7.atl.mindspring.net...
Captain Beefheart
burning temperature but I'd assume that it also increases the burning rate
and accordingly, the thrust for a given geometry.
Geoff
"Terry King" <tk...@together.net> wrote in message
news:MPG.16a79d7e5...@news.earthlink.net...
LOUIS
As the diameter of the particles decreases, the relative proportion of oxyd
increases vs the reactive metal!
Thus too thin is dangerous (risks of deflagration)or completely unreactive if
the metal is not pretreated! To big and the burning speed is reduced strongly!
PH Z
mine...@gmail.com
dowse...@gmail.com
normr...@gmail.com
> > I heard that a mixture of KNO3 and sugar
> > can be explosive. Does anyone know in
> > what ratio this mixture is explosive?
> >
> > Thanks!
> >
> >
Also, sugar doesn't melt at 100°C, so a double boiler is right out.
Finally, adding powdered magnesium to hot solution of sugar and nitrate just might get you a date with the local burn ward.
anuv...@gmail.com
7 potassium nitrate
3 sugar
