Weird Crystals forming in chlorate cell with graphite

[Scorpion812]

Hi everyone,

So over the last 4 or 5 days, a little test of mine using three battery rods as anodes and a titanium stick as cathode has been running on KCl, and there is a lot of graphite contaminated (likely) potassium chlorate, but now there are alot of blackish (but still purer looking than the black dust under it) crystals forming which kinda have a needle-like shape. Is this Chlorate or hopefully not chloride? if its KCl, can someone please tell me what i should do next?

 

Thx

Edited September 3, 2017 by Scorpion812

[WSM]

Hi everyone,

So over the last 4 or 5 days, a little test of mine using three battery rods as anodes and a titanium stick as cathode has been running on KCl, and there is a lot of graphite contaminated (likely) potassium chlorate, but now there are alot of blackish (but still purer looking than the black dust under it) crystals forming which kinda have a needle-like shape. Is this Chlorate or hopefully not chloride? if its KCl, can someone please tell me what i should do next? Thx

 

That's a good question and hard so say without knowing more. If you can separate the crystals from everything else, that would be a good first step in analyzing them.

 

What sort of battery did you get the graphite rods from? Maybe the crystals are something entirely different (manganese chlorate?!).

 

Good luck.

 

WSM

Edited September 3, 2017 by WSM

[Scorpion812]

 

That's a good question and hard so say without knowing more. If you can separate the crystals from everything else, that would be a good first step in analyzing them.

 

What sort of battery did you get the graphite rods from? Maybe the crystals are something entirely different (manganese chlorate?!).

 

Good luck.

 

WSM

thank you for this information, i think it is Kclo3, the rods are from a manganese dioxide battery and i think its graphite, i am currently recrystallisting a small sample. if its manganese chlorate, would that be useful?

[Scorpion812]

So, I took this little test from my cell (around 2g or so) and tried drying, redissolving it in boiling water and then hot filtering it to get out the graphite. Now, i used an extreme excess of water and after filtration, i immediately set the glass inside some cold water, and then in a freezer, but it hasnt yet crystallized. Does anyone know what to do, and if it is chlorate?. I am sure it contains some, but it doesnt wanna crystalize. Maybe should i just dry some dirty crystal, crush them, mix it with sugar and see if it burns at all?

[MrB]

If you used an extreme excess of water, evaporating some of should do the trick? It wont crystallize if it isn't a saturated solution.

[AustralianPyromaniac]

Remember though MrB that the solubility of KClO3 is like 3g/100ml at 0*C so it should be possible to get some precipitation even if a large excess was used say 50ml. How much water did you use Scorpion?

 

Regards, AP

[Scorpion812]

I dissolved around 1-2g in about 200ml

[MrB]

Remember though MrB that the solubility of KClO3 is like 3g/100ml at 0*C so it should be possible to get some precipitation even if a large excess was used say 50ml.

Since he said extreme excess for an estimated 2 grams of chlorate, i just assumed that was the issue. it generally is.

 

I dissolved around 1-2g in about 200ml

If you are at the lower end of that scale, you are looking at about 33ml as the point where it starts to fall out of solution at 0c.You probably need to get down to something like 10-15ml to get significant returns. Honestly, i would probably just evaporate of all the water with a weak heat-source, or, better yet, a vacuum.

[AustralianPyromaniac]

I stand corrected MrB! That is an excess. You would never have gotten precipitation at that concentration! What source of KCl are you using Scorpion? Could that be the problem?

 

Regards, AP

[Scorpion812]

I am using lab grade Kcl. Thank you for this information! Now, I found out that our freezer cools thing to only around 6°C, so i will have to recalculate this. Are there any tests to find out if this contains alot of chloride or just is chloride itself, which i dont hope and also dont think it is. the bottom now has a 4cm high crust of blackish crystals, and they looks really needle like. In the videos i saw, the kclo3 was always kind of flakey, but are needle also kclo3 or are it kcl crystals, cause kcl becomes needle shaped under certain conditions

[AustralianPyromaniac]

It is really only possible in a home lab to determine if ANY chloride or ANY chlorate is present but it's not really possible to determine how much of one or the other there is. Let me ask this. How did you prepare your starting solution as in, what concentration of KCl/L?

 

Regards, AP

[Arthur]

100ml of water holds 3.3g of KChlorate in solution at 0C so all your possible chlorate is in the solution. What can filtered out isn't chlorate, so filter it out and evaporate the solution to more like 10 to 20ml.

 

Filter using the smallest filter you can! With so little product present you do NOT want to throw any away in the used papers.

 

Consider GFA circles! Chlorate soaked paper when dried is highly flammable, Chlorate soaked GFA much less so (it's sintered glass fibres) It's used flat as it doesn't fold without cracking.

 

http://www.gelifesciences.com/webapp/wcs/stores/servlet/CategoryDisplay?gclid=EAIaIQobChMIoJbOvfSK1gIV7rztCh2ZhAZ_EAEYASAAEgJvuPD_BwE&categoryId=11237&catalogId=10101&productId=&top=Y&storeId=12751&langId=-1

[Scorpion812]

It is really only possible in a home lab to determine if ANY chloride or ANY chlorate is present but it's not really possible to determine how much of one or the other there is. Let me ask this. How did you prepare your starting solution as in, what concentration of KCl/L?

 

Regards, AP

I made boiling water and added KCl until it started to crystallize on the pot and then stopped. I also mixed it with solution of an older run. There are alot of new crystals now.

Edited September 4, 2017 by Scorpion812

[Scorpion812]

my cells temperature is around 32-35 °C

[AustralianPyromaniac]

Ok that's your problem! You should have made a 400g/L solution but using that technique you would have got a much higher concentration than that. Then, I imagining, when the solution cooled in the cell the excess KCl presipitated quickly giving a fine powder and what deposited on top of that was chlorate and a little bit of chloride which mixed with the graphite as would be expected giving the observed result. One more question. How soon after the run started did you notice ANY crystals or powder forming? Not including the graphite.

 

Regards, AP

[Scorpion812]

crystals started to form i think 4 days after start but im not sure

so do i have any chlorate in this black stuff?

[AustralianPyromaniac]

That contradicts my theory. My opinion is that you likely have only chlorate and graphite deposited simply because I can't think of anything else it could be. Its unlikely to be chloride because it was all in solution for 4 days and there is no reason for the solubility to spontaneous decrease. Unless you added something? I recommend you just get it out of the cell, filter and recrystallised it then mix it with some fuel and see how it burns. That's probably the best test.

 

Regards, AP

[Scorpion812]

That contradicts my theory. My opinion is that you likely have only chlorate and graphite deposited simply because I can't think of anything else it could be. Its unlikely to be chloride because it was all in solution for 4 days and there is no reason for the solubility to spontaneous decrease. Unless you added something? I recommend you just get it out of the cell, filter and recrystallised it then mix it with some fuel and see how it burns. That's probably the best test.

 

Regards, Ap

I havent added anything, now, i spent the last couple hours getting the graphite out of the kclo3 and ended up with like less than 10 grammes of yield, but i havent boiled the liqour yet and havent collected the crystals that appear when you turn of the cell. i will test them later. I am kinda disappointed, as i expected around 100g kclo3. But i ordered a lead dioxide anode and an mmo, so that will probably be a better run.

i think there should be a complete step by step guide here on how to get the kclo3 out of a graphite KCl cell

[Scorpion812]

I just tested the stuff, it burns fast as hell with sugar, 5g gone in an instant

[Scorpion812]

I just tested the stuff, it burns fast as hell with sugar, 5g gone in an instant

Also is it normal if thsi stuff really smepls like bleach? Because i didnt destroy hypochlorites yet

[AustralianPyromaniac]

Well, congrats! You got chlorate. Chloride wouldn't have that effect. Also, that smell is completely normal and it isn't strictly nessasary to distory it so that's fine although it will decrease the yeild

 

You probably recovered the chlorate wrong to get such a small yeild or didn't run the cell long enough. The correct procedure is to heat the solution to get eveything to dissolve; filter; and cool slowly to 0*C. This should give very pure crystals of KClO3. Did you do this?

 

Regards, AP

[Mumbles]

I would consider it 100% necessary to destroy chlorite and hypochlorite before using it in any compositions.

[Scorpion812]

Well, congrats! You got chlorate. Chloride wouldn't have that effect. Also, that smell is completely normal and it isn't strictly nessasary to distory it so that's fine although it will decrease the yeild

You probably recovered the chlorate wrong to get such a small yeild or didn't run the cell long enough. The correct procedure is to heat the solution to get eveything to dissolve; filter; and cool slowly to 0*C. This should give very pure crystals of KClO3. Did you do this?

Regards, AP

Well, i sadly was very very stupid and didnt heat it because i dont have a hot plate and dont want tl use my stove. I just filtered all the dirty crystals out, collected the stuff that precipitated because of the cell cooling down, the calculated the water i had to use, got some boiling water, dissolved the black crystals, filtered it and immediately collected the crystals and didnt let it stand. I really sadly poured a lot down the drain, and i am embarrassed

[AustralianPyromaniac]

What is your reasoning for that Mumbles? I have always thought that the presence of chloride would make no difference in small quantities and the hypochlorite would act as a base neutralizing any acidic compounds decreasing the risk of spontaneous combustion. It is true that hypochlorite is a strong oxidizer but so is chlorate and metals aren't oxidised by chlorate when in a composition partly I belive becase of how reactive potassium is. Certainly not a chemist and would love to know if I am wrong.

 

Regards, AP

[Mumbles]

Chlorite isn't the same as chloride. Hypochlorites and chlorites are just more unstable than chlorate. It's mostly the mixing of hypochlorite with organics that would concern me. Bases are also more damaging to certain metals as well.

 

As an aside, but chloride contamination does increase the sensitivity of chlorate compositions too.