vesnicketopg
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potassium perchlorate
hello i was rewatching old codyslab videos and saw that he used ammonia perchlorate to get potassium out of solution and made potassium perchlorate
and since i cant buy kclo4 where i live but i managed to get 500g of NH4ClO4 i was wondering if there is a reasonably efficient way to convert the
NH4ClO4 to kclo4 and than convert that to kclo3 im quite new to doing chem so id apriciate all opinions (sorry for my english its not my first
language)
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Keras
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I’m not sure you can go from ammonium perchlorate to potassium perchlorate by salt metathesis. Try it out, e.g. by mixing with KCl. Potassium
perchlorate is almost insoluble at low temperatures, so it should be easy to isolate, provided the reaction works in the first place.
As to reduce perchlorate to chlorate, I've no idea if that can be done directly. But potassium chlorate is easily made from bleach and KCl, so
there’s no need to figure out tedious pathways to it.
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woelen
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Potassium perchlorate can easily be made from ammonium perchlorate.
Buy pure KCl and take 1 mol of that. Take also one mol of NH4ClO4.
Dissolve both chemicals in very hot water. Prepare concentrated hot solutions. Mix the two solutions. You'll get a precipitate of KClO4 immediately,
but that is not what you want. It is impure. Heat the solution till near boiling. Probably not all of the precipitated KClO4 dissolves. Add small
amounts of water stepwise, while keeping the solution near boiling. When all of the solid material has dissolved, then add a few ml of additional
water, while keeping the liquid hot and stir that through the solution. Now you have a clear very hot solution. Set this aside for a few hours, such
that it cools down to room temperature. You'll see formation of many large crystals, at thye bottom, but also at the surface of the liquid. After
cooling down, put the liquid, with all the crystals in it, in the freezer, and allow it to cool further. The liquid, however, should not become
frozen. When the liquid is cold (a few degrees below zero), then decant it from the crystal mass. Put the crystal mass on a coffee filter, which in
turn is put on a pile of paper tissues or toilet paper. Allow all water to be sucked out. Next, take the crystals between layers of coffee filter and
press this between two piles of paper tissue. In this way you get almost dry crystals and you remove nearly all of the adhering water, which contains
impurities.
After this step, you have one batch of quite pure KClO4. You can make it even purer, without too much loss by dissolving it again in as little as
possible of boiling water. Then you repeat the step of cooling down, putting it in the fridge and drying with a coffee filter and a pile of tissue.
After this second run you get really pure KClO4. Let it dry in a clean dish in a warm place, free of dust.
Conversion to KClO3 is nearly impossible. The other way around is possible and thermodynamically favorable, but forget conversion of KClO4 to KClO3.
If you want KClO3, then it is much easier to make it from KCl by electrolysis.
Why do you want KClO3 instead of KClO4? For aqueous chemistry I can understand that (KClO4 is really inert in aqueous solution and does not show any
interesting reaction). For pyrotechnics experiments, however, KClO3 is too dangerous, you would not be the first one with missing or damaged limbs and
nasty burns.
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vanBassum
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I thought it went the other way?
I have made ammonium perchlorate, I can't recall if I used KClO4 or NaClO4.
Ammonium Perchlorate from K or Ba Perchlorate
- http://www.chlorates.exrockets.com/ammper5.html
BTW, If you want chlorate, you can easily make it yourself. Electrolysis is by far the winner. Or, if you need just a little bit, you can boil bleach.
[Edited on 6-10-2023 by vanBassum]
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Conure
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Are you in Europe? If so you can buy legal but rather expensive water diluted KClO4 from https://pyrohub.eu/product/pyro-liquid-kclo4-h2o/.
I ordered 500g of KClO3 from there once and let it dry. Another time I ordered 500g of KClO4 and ended up getting 1kg of dry KClO4. 
Fire is good. Fire is life.
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Bedlasky
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In Europe you can buy mixture of NaClO3 with NaCl with NaClO3 content <40%. You can pretty easily isolate KClO3 from this by using potassium
nitrate or acetate (I wouldn't use chloride, because NaCl limits solubility of KCl).
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Keras
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KClO₃ is very easy to make from bleach. The best way is to make you own bleach, by bubbling chlorine gas (TCCA + HCl) into a hot (80 °C +), stirred
solution of NaOH (so that salt does not clog your tubing) until the solution turns green (at which point there is no lye left, and only chlorine
dissolves). Add KCl to the hot filtered mixture and let cool down, and Bob's your uncle! 
I let you figure out the numbers, but this works quite well, provided you set the quantities for the extra NaCl to remain dissolved in the water. Wash
your crystals with ice-cold water if you want to improve purity. I used this potassium perchlorate to make potassium permanganate (cf. Nurd Rage's
recent video) and it worked like a charm.
[Edited on 22-10-2023 by Keras]
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unionised
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"a reasonably efficient way to convert the NH4ClO4 to kclo4 and than convert that to kclo3 "
The first bit is easy.
Add KOH solution to NH4ClO4 solution, and let the ammonia and water evaporate off (outdoors).
Reduction to chlorate will be difficult.
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