Armistice19
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Potassium chlorate
Just the other day I decided to synthesize some potassium chlorate from a sodium hypochlorite solution. I got my camping stove, an old glass coffee
pot, a frying pan, and some oil. I used the oil as a buffer and began to boil my solution in the coffee pot. The process went well. Once the sodium
hypochlorite had reduced to about 3/4 I added about 7 tablespoons of Potassium chloride while the solution was still boiling, then I let it reduce for
a slightly longer period of time. I then took my solution and put it in the fridge. The KCLO3 precipitated out, and I removed the solidified crystals
with a spatula, and placed them on a sheet of aluminum foil. I then acuired an oven sheet pan, and baked my chlorate at about 125*F. This went well,
and I removed the crystals when they were completley dry. Sadly, it seems that the chlorate ate through the aluminum foil during the drying process.
When I went to lift the foil from the oven sheet pan it was adhered to it quite firmly. The foil seems to have ripped, and now I can only salvage 50%
of my original yeild. How can I prevent this from happening again?
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UnintentionalChaos
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learn to use glass. metals and oxidizers rarely get along.
Department of Redundancy Department - Now with paperwork!
'In organic synthesis, we call decomposition products "crap", however this is not a IUPAC approved nomenclature.' -Nicodem
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Armistice19
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I suppose I will use a glass baking pan from now on. I tested my chlorate today with sugar. It was very dissapointing. I mixed 2 parts sugar with 3
parts of my homemade chlorate. I then used a mortar and pestle to grind the mixture. It was difficult to ignite, burned yellow instead of purple as
expected, and it went out frequently as it burned extremley slowly. Whats going on here? The flame is yellow, but why would sodium chlorate
precipitate out? It's burning slowly, is this because of sodium chloride impurities? Perhaps it is still not dry enough?
“Imagination is more important than knowledge. For knowledge is limited to all we now know and understand, while imagination embraces the entire
world, and all there ever will be to know and understand.” -Albert Einstein
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kmno4
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Quote: Originally posted by Armistice19  | | I suppose I will use a glass baking pan from now on. I tested my chlorate today with sugar. It was very dissapointing. I mixed 2 parts sugar with 3
parts of my homemade chlorate. I then used a mortar and pestle to grind the mixture. It was difficult to ignite, burned yellow
instead of purple as expected, and it went out frequently as it burned extremley slowly. Whats going on here? The flame is yellow, but why would
sodium chlorate precipitate out? It's burning slowly, is this because of sodium chloride impurities? Perhaps it is still not dry enough?
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You are very lucky that your chlorate is very impure.....
Chlorate+sugar= very dangerous mixture in your hands (or rather mortar).
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hissingnoise
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Ordinary bleach is laced with NaOH as stabiliser and it eats Al for breakfast. . .
NaOH also messes up chlorate-making.
Reading up on chlorate preps would be an idea!
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hissingnoise
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I think you're exaggerating the danger kmno4!
Mixed with sulphur or red P, chlorates are sensitive but chlorate/sugar is fairly forgiving, I've found. . .
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kmno4
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I am not going to disscuss about it.
I know example when same technical grade KClO3 blown out of mortar during griding. I also know that KClO3+S needs a hammer to go. I also know that
KClO3+P is extremely dangerous (especially when P contains traces of acids) and explosion can be caused by a touch (or even without it - I know such
an accident:
someone dried this mixture [made by mixing KClO3+P under water] and during drying in the air it exploded).
I also know that sugar+KClO3 is between these ones described above.
Grindig it in mortar will surely cause explosion.
It belongs to scale and luck if you lose your eyes or not.
Have a nice grinding 
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Formatik
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Grinding chlorates with solid oxidizable fuels in anything over a few mg is a very dangerous operation. Federoff describes the KClO3 and sugar mixture
detonable by flame, heat, impact or conc. H2SO4. Also, KClO3 itself is shock sensitive, but not very: a 20kg weight dropped from 16 cm gave a
detonation and another time a deflagration out of 6 tests. Federoff further states both NaClO3 and KClO3 explode from strong impact if they are above
their melting points.
Concerning aluminium and chlorate. The finely divided mixes are flash powders as many know, but Gmelin states that molten KClO3 does not noticeably
react towards aluminium even after some time. Bad news for iron containers: Iron gets attacked by molten -ClO3 (oxidized rapidly to Fe3O4). NaClO aq.
itself will attack Fe readily. Stick a few nails in some bleach, over a few hours a significant amount of rust forms.
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Taoiseach
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Recently a french anarchist blew himself up while preparing an IED from NaClO3+sugar. Grinding these two chemicals together in a mortar is exceedingly
stupid.
As for the flame being yellow: Even minute amounts of Na+ will color the flame yellow. You might expect decently pure crystals of KClO3 after washing
and recrystallizing it at least two times.
Also when you make chlorate from bleach, remember that only 1/6 of the OCl- is converted to ClO3-. 5/6 are turned into useless Cl-. How did you remove
the NaCl? Normally you would boil down the chloride/chlorate solution until NaCl precipates out, then filter hot and add the KCl. This works well
because NaCl's solubility is relatively constant while NaClO3 is much more soluble in boiling water.
If no crystals fell out during boiling, you didn't boil long enough.
Either way, your chlorate is full of NaCl.
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ScienceSquirrel
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Several years ago a boy in the UK had a serious accident with a home made bomb made out of a paint tin filled with sodium chlorate and sugar.
He was hammering the lid down when it exploded.
Grinding or compresssing an oxidiser and a fuel together is really not advised.
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woelen
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Oh yes, I fully agree with KMnO4, you should NOT grind any chlorate/fuel mix. That is asking (even stronger: begging) for big trouble. Always grind
the chemicals in separate vessels and then carefully mix them.
I have made a demonstration of the sensitivity of phosphorus/KClO3 mixes. Just gently tapping the mix with a rounded/smooth glass rod is enough to set
off the stuff:
http://woelen.homescience.net/science/chem/exps/raw_material...
[Edited on 6-5-09 by woelen]
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hissingnoise
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For the record, I'm not suggesting that sugar/chlorate mixes are non-hazardous, but I've powdered such mixes with mortar and pestle many times without
incident.
And always with slow, steady grinding movement.
The way you guys are talking---I should be pushing up daisies long ago. . .
Charmed life?
I've even got a couple of fingers left. . .(wink)!
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Bikemaster
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KClO3/sugar is not a super dansgerous mix but it is like all other pyrothecnique mix...take care of it. For wath i know, this mix will explode with a
good hammer hit. I am not very sure that if you use gentily a motar/peste, that it will explode but you never know wath you have il you chlorate or
your sugar (if it is acidic it is very dangerous), so always take more seafty that you really need.
I make a lot of this mix, like 100g at ouce, but i always grind my stuff before to mix if and after mix it gentily with a big wooden spoon. never had
problem. (i always work with 99,5% kclo3... because i make it and i never work with 99,99% kcl03, maby it is really more sensible???)
But with explosive stuff, always think that it is dangerous, because loose and hand don't seem to be really nice
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Armistice19
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Chlorate Sensitivity
I would like to mention that the chlorate sample I have here is in no way technical or laboratory grade KCLO3, It was the first time that I had ever
attempted to synthesize a chlorate. It was some stuff I made with some clorox, a camping stove, and an old glass mr coffee pot. There is a huge
difference between this and pure laboratory grade KCLO3. I'm going to have to completely agree with hissingnoise.
As for the grinding of chlorate and sugar, I was always lead to believe that the only shock/percussion friction sensitive chlorate mixtures were with
Sulfur, Phosphorus, and if I'm not mistaken, aluminum powder. I had no idea that chlorate and sugar was so dangerous. I always thought it was a slow
deflagrating mixture. Do you think if I ground them separately and then mixed them in a ziplock bag it would be safer? I use that method with
magnesium and nitrate for film special effects.
Taoiseach, your saying that if you boil bleach that the first thing that precipitates out is NaCl? Well perhaps what I have here is not potassium
chlorate contaminated with NaCl, but rather NaCl contaminated with potassium chorate. Well I have about 3 cups of the solution still left in my fridge
with the first layer of X precipitate already skimmed off which is obviously not burning well, what do you suggest I do with the rest of the solution?
[Edited on 7-5-2009 by Armistice19]
[Edited on 7-5-2009 by Armistice19]
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world, and all there ever will be to know and understand.” -Albert Einstein
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hissingnoise
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You could check the pH for one thing---I think you'll find it high from residual NaOH.
If it is high, neutralise with HCl and recrystallise.
Dissolve the precipitate to form a saturated sol, add a couple of spoons of KCl and recrystallise again.
This should give KClO3 of acceptable purity. . .
Chlorate from bleach is always iffy---if you want usable amounts you could UTFSE---there are several threads on various chlorate syntheses. . .
[Edited on 7-5-2009 by hissingnoise]
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Armistice19
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I have UTFSE, and I'm not big into electrolysis or chemical supply stores. Thank you for the advice on the acid base neutralization. I will use some
of my spare muriatic acid and I have some extra Ph Tester strips that I can use.
[Edited on 7-5-2009 by Armistice19]
[Edited on 8-5-2009 by Armistice19]
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world, and all there ever will be to know and understand.” -Albert Einstein
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hissingnoise
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A non-electrolytic method relies on bubbling Cl into a hot, saturated NaOH solution---a proportion of NaOH will be converted to NaClO3 and this can be
separated from the NaCl by-product by fractionation. . .
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Formatik
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Note that if you neutralize the NaOH with an acid - even carefully - I've found some of the NaClO will also decompose giving off Cl2. If just too much
HCl was added, then a large amount of Cl2 evolution occurs. Even with careful neutralization, since the NaClO concentration is already low, loss could
be significant. Using the NaClO to generate Cl2 and bubble into warm aq. NaOH could be better as far as yields go, but you better be prepared to deal
with the highly poisonous Cl2. You also very urgently need to prevent suckback if bubbling gets weak. Though NaOH is a strong base, it should wash the
Cl2 well.
[Edited on 7-5-2009 by Formatik]
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Armistice19
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Formatik, thank you for the warning, I will take caution and go either outdoors or under a fume hood. I have some calcium hypochlorite and muriatic
acid, as I mentioned before, that I can use to generate Chlorine. Hissingnoise, I'm assuming that the NaCl will precipitate first before the NaClO3
during fractionation?
[Edited on 8-5-2009 by Armistice19]
“Imagination is more important than knowledge. For knowledge is limited to all we now know and understand, while imagination embraces the entire
world, and all there ever will be to know and understand.” -Albert Einstein
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hissingnoise
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Ebay UK has cheap sodium chlorate---US ebay prices are grossly inflated.
Easier than making it. . .
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hissingnoise
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Yes it will---3Cl2 + 6NaOH--->NaClO3 +5NaCl + 3H2O
NaCl will precipitate as the solution is concentrated---chlorate as the solution cools.
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Taoiseach
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Armistice19 , this synthesis is hardly gonna work without some calculcations.
Check the conc. of your bleach. Now u know how much NaOCl is in there and you can calculate how much NaCl and NaClO3 is formed during boiling. Check
the solubility data for these salts:
http://en.wikipedia.org/wiki/Solubility_table
Now boil down the solution until there is just enough water left to dissolve all the NaClO3 @100°C. Plenty of NaCl should have precipated at this
point. Filter hot. Knowing how much NaClO3 you have, calculate exactly how much KCl you need and how much NaCl will be produced: NaClO3 + KCl --->
KClO3 + NaCl
Check pH - if NaOH is left, neutralize with muriatic acid.
Boil down the solution to the point where there is just enough water to keep all the NaCl in solution @0°C (add a little extra water in case you had
to neutralize the solution). Then put it in the fridge. Recrystallize twice...
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Formatik
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If your calcium hypochlorite is several years old, be careful in using it as a Cl2 generator. Because over time it decomposes to chlorate, so when
that reacts with acid, there is also some ClO2. To prevent suckback without using a saftey bottle you can connect an airpump to push the Cl2 out
continously. Suckback can get very dangerous near the end or when significant amounts of chlorate have formed, when the chlorate concentration is high
and if that gets sucked into the acid generator, that will be an explosion hazard (ClO2). So as long as using a pump the only thing about that that's
bad is if the electricity fails. If you do use Cl2 outside make sure to still wear a gas mask, because of wind gusts or vapor drifts.
The sodium chloride does crystallize out on boiling, as sodium chlorate is much more soluble. Also the solubility of NaClO3 in NaCl aq. and vice versa
varies with the amounts of each in solution (chart, but only for room temp.). Also, you don't need NaOH. You could chlorinate the NaClO aq., though the Cl2 will not get washed very good and
the amount of sodium is rather low in bleach, it should require a more careful chlorination too.
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