Making Potassium Chlorate

mrjeffy321

that is essentially the way I do it now, but it is so time consuming, keeping all those records of what the current was at each interval.
also, when I cant tend to it all the time (like when I goto sleep), alot of times it stops because of some problem, and i never know when to estimate the stopping time was. if I can find one cheap enough, it think it would worth it to me convience wise to get one.

I am roughly into my 440th amp hour on my second trial of my chlorate cell, only about 210 more to go.

mrjeffy321

OK, it is finsished after long last, my second trial is done, the Chlorate has been extracted, dried, and weighed.

Stats:
-Started with 180 grams of NaCl
-dissolved in 500 mL of water
-should have taken 650 ah to convert 90% of it at
-estimated 55% efficency (what I estimated it would be from the begining)
-I ran it for the full 650 ah, by my log (which inclues soem rounding, but more on that later).

Theoretical maximum amound of KClO3 that could have been made by convering 90% of the 180 grams of NaCl: 272 g.

Actual yeild: 140 grams
% success: 51.5$
Actual efficency: 28.3 %


This is pathetic, I am ashamed of these results, it is stuff like this that makes me think I forgot a decimal somewhere because this is horrible!
I let this cell run for the entire month of Feburary to get the 650 ah needed, then I spend a week extracting it and letting it dry, crush it up and weight it, and all I get is a measly 140 grams, (just a small jump from my last cell), and I should have theoritcally gotten 272 grams.
sure is alot compared to how much I used to be making, but I spent so much time on this, changing electrodes, keeping careful logs, adding HCl, ...... and something must have gone terribly wrong for me to get only 28.3% efficency, I could have done nothing and got better than that. I did do some rounding and estimating, but I dont think this could have made that huge an impact on my results.

This really makes me want to redesign my cell, but there are so many complications, I dont know where to start.
if/wheh I redesign it, its main purpose would be to produce chlorate, but I also want to be able to collect/divert all the gasses (speratly) that come off the electrodes.

redwraith94

mrjeffy321: Boiling bleach decomposes it from 3 x NaClO to 1 x NaClO3, 2 x NaCl

Platinum electrodes can be used, but they have to be uber pure, even .01% rhodium/some other similar group metal will give the electrode a set service life...this is considering electrodes that are usually copper core, niobium alloy 1st plating, then platinum over-plating (usu ~100-250 microns thick or so)

Graphite works fine, and they are much cheaper, I just got a quote for platinum clade copper rods. 2 x rods 1 foot long each with a 100 micron plate 1/4 inch full diameter...90 dollars US...too much money for an electrodes w/ ~5,000 hrs service life? lol.

Finally, don't be ashamed of your results. A big thing that comes into play for electro-chemistry is current density, temp, ph etc. You really want fairly large electrodes for your setup. I am doing research right now, because I am also looking to make a Chlorate/sugar/Ammonium sulfamate/dye based smoke bomb for the fourth.

Letda

hey guys, im new at all this so dont judge me right away. I'v been researching how to make the potassium chlorate for about a week now w/o actually doing a lab. I'v read everything that had been posted, but im still a little lost. I was just wondering if one of you could break down the steps in lame'ns for me. I run an IQ of 147, knew frued before i knew freud, but chem.... i sometimes wonder. If anyone can talk one on one with me to help me understand i might be of some value to your conquest. Just E'mail me at -letda13@hotmail.com-. otherwise ill be reading up on your findings and starting my experiments my self. Ill post everthing i find i promise :)

mrjeffy321

Hello, I have been researching/making potassium chlorate for about 9 months now, so I have gotten plenty of experience by now.

Do you have any specific questions, or do you just want general information on the process(es).
Like redwraith94 mentioned, this is a popular time to start making KClO3, only about 2 weeks left until the 4th of July (and all the homemade fireworks that go with it [taking all necesary precautions of course]).
If you want to make alot of Potassium Chlorate in a short amount of time, I would go with the decomposition of hypochlorite method (boiling bleach), but if you have more time and are patient enough, the potential for gain using the electrolytic method is much greater. I myself prefer the electrolytic method, but I have been plagued by bad luck with it also, using hypochlorite is certainly provides much quicker results (and some might consider it easier).
I actually have a batch of KClO3 drying right now.

Letda

I guess I’m kinda of an unusual person, I’m a psychology major with a weird fascination with astrophysiology and aeronomics, so I guess I’m not trying to make "just" fireworks for the 4th of July but I want to use concepts from these basic principles to further my know how in such matters....

So, when boiling the bleach, do you just boil until no liquid is left or do you get the crystals before that, and are they what I need in pyrotechnics? And I’m totally unfamiliar with electrolytic, is that just like putting a positive charge on one end of the cup and neg. on the other end??? As you can see, at 17, I think I'm a little behind, I was too cool to take chem. serious in school.... how sad huh!

mrjeffy321

The bleach boiling method is easiest to understand.
Bleach is a solution NaOCl (sodium hypochlorite), and generally it has alot of other stuff in there too, I know that clorox bleach is 6% NaOCl, 5.63% NaCl, and .015% NaOH, and the rest it is just inert stuff and/or water. All you are concerned with right now is the NaOCl.
When you boil bleach, the NaOCl decomposes to form NaClO3 and NaCl,
3NaClO --> NaClO3 + 2NaCl
Sodium hypochlorite is very soluble in water (100 g / 100 mL), but sodium Chloride not so much by comparison. So the trick is getting the maximum possible amount of NaClO3 dissolved in the smallest amount of water possible and not have very much "other" stuff in solution, like NaCl.

This page,
http://www.wfvisser.dds.nl/EN/chlora...therm_starting
gives instructions on how to make chlorate both using electrolysis and thermal decomposition of hypochlorites.

You will see in those instructions that you are suppose to boil 1 L of 4% bleach down to 140 mL. If you do the math (and I have), you will find that this is alot more than is really necesary to hold the amount of NaClO3 you will have left after decomposing the NaOCl. The reason is because there is all that other stuff in solution too. Actually, in practice, if you follow those instructions, there will be NaCl comming out of solution even before your done boiling.

Anyway, so now you have a solution of NaClO3 and some NaCl. But you wanted KClO3, not NaClO3!! to turn the sodium chlorate into potassium chlorate, you can use a double replacement reaction between the NaClO3 and KCl. The potassium ion will push the Sodium out of the NaClO3 and replace it, and then the Na ion will join up with the Chlorine ion,
NaClO3 + KCl --> KClO3 + NaCl

After you do this, you should notice a white percipitate forming. This because unlike NaClO3, KClO3 is not nearly as soluble, not even close.
But to maximize yeild, we want to get all the KClO3 out that we can, so we cool the solution down to just around 0 degrees celcius, and then filter out the percipitate, which will be mostly KClO3 and some NaCl.


The Key to the whole reaction is that bleach (NaOCl) will decompose and form NaClO3, which can them be turned into KClO3.

the electrolytic method is much more complex, but is explained in the web page provided above.

Letda

I understand this alot better than before, so thnx. But, where do you get potassium chloride, is that the salt substitute? and is the NaCLO3 worth anything in that form or must the Na be replaced with the K?

mrjeffy321

I buy my Potassium Chloride as a salt substitute, called, "NoSalt", there are also salt substitutes (I think called "LoSalt"), but these also contain a large part sodium chloride, you want to get the one with as much potassium chloride as possible.
Sodium Chlorate is in itself worth something. It will react very similar to KClO3, but because of its high solubility, it is hard to extract. alot of the time in chemical formulas for pyrotechnic things, KClO3 and NaClO3 are interchangeable.

Letda

so let me make sure im understanding this. When you boil the bleach, you get NaClO3 crystals after filtering the liquid, or is the liquide the NaClO3?

mrjeffy321

by boiling bleach, you make NaClO3 AND NaCl.
Since NaClO3 is so much more soluble than NaCl, most (or all) of the crystals that percipitate out will be NaCl, and the NaClO3 will remain in solution.

Then when you add KCl, you make KClO3 and NaCl. this time NaCl is much more soluble than KClO3, so most of the percipitate is KClO3 and then NaCl remains in solution.

Letda

Thnx,i just bought everthing 10 mins ago so ill be testing everything tomorrow, ill let you knogw how things o. thnx for all of the help.

Letda

well, my first run was a complete and utter failure....all i got was a bunch of brown and black stuff. I filtered it out, added the KCl and recooked...same thing...and i got no noticable crystals the first time? i guess ill start round two here in a bit...any suggestions?

Letda

ok, i managed to get KCl pure crystals using the boiling process, but i dont know how the bleach is suppposed to work, i boil and all i get is a bunch of brown and balck crap. no crystals form, im i boiling to much or not enought or what?

mrjeffy321

Are you following the instructions in the link I provided a couple posts back,
http://www.wfvisser.dds.nl/EN/chlora...therm_starting
I found if you follow these instructions pretty closely, you will have very good results, although some deviation can be made to see what works best.

You should boil the bleach in a pyrex / heat resistant glass container optinumy, definatly not metal.

Letda

i was using metal, it said stainless steel on the site if i remeber right. i guess ill get glass then. Ill get back to you when i use the glass.

mrjeffy321

I used to use stainless steel, and I kept getting some brown stuff in the mix while boiling. At first I thought it was a product from the reaction, although I couldnt explain what it was, and now I realize that it was most likely Iron Oxide being made when the bleach oxidized the Iron in the pan (my first clue is when it ate throught the pan and I had a big hole in it).

Glass is definatly best, although you need to be more careful with it. I use a old coffee pot that can take the heat.