making potassium (per) chlorate

[royster]

The USB hypochlorite electrodes as from China should make chlorate given enough time and temperature. However most folk here want to make more than their 1amp current rating suggests. But at current China prices they are a good start, just harvest product after a month of 24/7.

I know i just thought it was really cute. It was on 24 hours and started producing, i took out about 1.5 grams. Added a little more water and saturated the solution again last night, now it looks like theres about 4-5 gram at the bottom.

 

Im just playing around. This thing supposed to go on for 5 minutes at the time, but i guess its defective it stays on until unplugged.

[Arthur]

If you have fully read Swede's posts in this thread and his blog on here you will find his calculations about the number of amp hours required per gram/mole or kilo of chlorate. (it's a big number)

[royster]

So I've been reading many many pages in this thread but i would still like to ask a few question.

 

I've been running a small 500ml chlorate cell for a few days, yesterday i filtered the goodies and then re saturated the juice with kci. After filtering there was a lot of precipitation happening, had to filter 3 times to get it clear. Is that stuff worth saving? Or worth recrystalizing? Is there a way to avoid it? Doesn't seem very pure.

 

Can perchlorate be made with 10A or 20A is crucial?

 

 

Has anyone worked an easy way to thermally decompose kclo3?

 

I tried doing that in 100ml porcelain crucible, took about 2 hours to fully decompose, my heat source was a portable burner lol, then i re crystallized it and ended up with about %30 weight of what i started with, and it probably still has a good amount of kclo3 in it. It stunk.

 

I want to end up with kclo4 as it seem more compatible for pyrotechnics and less likely to cause an issue if i make any mistake.

[WSM]

So I've been reading many many pages in this thread but i would still like to ask a few question.

I've been running a small 500ml chlorate cell for a few days, yesterday i filtered the goodies and then re saturated the juice with kci. After filtering there was a lot of precipitation happening, had to filter 3 times to get it clear. Is that stuff worth saving? Or worth recrystalizing? Is there a way to avoid it? Doesn't seem very pure.

Can perchlorate be made with 10A or 20A is crucial?

Has anyone worked an easy way to thermally decompose kclo3?

I tried doing that in 100ml porcelain crucible, took about 2 hours to fully decompose, my heat source was a portable burner lol, then i re crystallized it and ended up with about %30 weight of what i started with, and it probably still has a good amount of kclo3 in it. It stunk.

I want to end up with kclo4 as it seem more compatible for pyrotechnics and less likely to cause an issue if i make any mistake.

 

 

The required current is dependent on the surface area of the anode.

 

I had success applying 0.1 to 0.2 Amps per square centimeter of the (platinum or lead dioxide) anode for sodium perchlorate production from sodium chlorate solution. I was using a small laboratory power supply on constant current mode.

 

Adding potassium chloride (KCl, that's a lower case L, not an i) to the depleted electrolyte will recharge it for further running of the potassium chlorate cell.

 

WSM

[WSM]

If you have fully read Swede's posts in this thread and his blog on here you will find his calculations about the number of amp hours required per gram/mole or kilo of chlorate. (it's a big number)

 

 

Yes, that's true. The numbers can also be found in my blogs, Homegrown Oxidizers.

 

WSM

[WSM]

I know i just thought it was really cute. It was on 24 hours and started producing, i took out about 1.5 grams. Added a little more water and saturated the solution again last night, now it looks like theres about 4-5 gram at the bottom.

Im just playing around. This thing supposed to go on for 5 minutes at the time, but i guess its defective it stays on until unplugged.

 

 

Those small systems will be okay for a "Proof of Concept" small cell.

 

But, if your goal is to produce workable amounts of potassium chlorate in less time, I suggest using larger electrodes in a bigger cell (consider a "bucket cell" system) and run it at about 0.3A/cm^₂ of anode surface area. These types of cells usually need to be built by the operator and fine tuned as they develop. Some amateur electrochemists are able to buy electrodes ready-to-use on eBay or other sources. When laserred was still selling MMO on eBay, many were able to access bulk MMO anode material at greatly reduced prices, which could be cut to size and spot welded to power leads, to make their own custom electrodes.

 

WSM

Edited November 6, 2020 by WSM

[royster]

Im just a back yard pyro, i want to make some color stars and salute rockets maybe, whistle and strobe is something i hope to get into at some point, but i won't attempt that any time soon, so i dont really need large quantities.

[Arthur]

If you have no access to perc by commercial means, then chlorate production is easy, there are hundreds of compounds that used to be in general use that use chlorate, BUT usually they are more sensitive than perc comps. The full perc process once you have the knowledge (it's all here) and the skill, is just something that can largely be left to itself for days/weeks/months.

 

One US firm used to make DIY kits for the process apparatus but they are long gone. It's now necessary for you to have some serious interest in the lab work and a willingness to make your own apparatus. Fortunately titanium has arrived on the hobby market (mostly ebay) and MMO and PbO2 is available from China.

 

There is so much to read here, -this thread from the start, -Swede's blog and WSM's blog to occupy you for the winter! However no-one will sell you a "complete apparatus" it's too small a niche to custom make a profit.

[rogeryermaw]

 

 

Those small systems will be okay for a "Proof of Concept" small cell.

 

(consider a "bucket cell" system) and run it at about 0.3A/cm^₂ of anode surface area.

WSM

 

um...sorry to ask a stupid question that has probably been answered here, but how do you calculate the surface area of expanded steel substrate?

 

i'd really hate to just completely destroy these nice new platinum plated anodes faster than i have to....

 

and is it better to use mmo to get to the chlorate stage and then switch to the platinized to push to perc?

Edited November 5, 2020 by rogeryermaw

[WSM]

um...sorry to ask a stupid question that has probably been answered here, but how do you calculate the surface area of expanded steel substrate?

 

i'd really hate to just completely destroy these nice new platinum plated anodes faster than i have to....

 

and is it better to use mmo to get to the chlorate stage and then switch to the platinized to push to perc?

 

The rule of thumb about MMO mesh is, due to the high surface area (on a microscopic level), it has roughly the same surface area as solid MMO. So the short answer is just measure the length and width in centimeters, then multiply the two numbers to get the square centimeters of one side. Multiply that number by 0.3A to estimate the current demand of the cell using a single cathode.

 

Also, if using two cathode plates (on opposite sides of the anode) then double the calculated Amps to figure the current demand of your cell.

 

Run lower current for your perchlorate cell than is used for the chlorate cell. I had success running perchlorate cells at 0.1 to 0.2 Amps per square centimeter.

 

I subscribe to the notion of using MMO for chlorates and either platinum or beta-form lead dioxide anodes for perchlorates.

 

WSM

Edited November 6, 2020 by WSM

[rogeryermaw]

you're the man! thanks brother!

[WSM]

The rule of thumb about MMO mesh is, due to the high surface area (on a microscopic level), it has roughly the same surface area as solid MMO. So the short answer is just measure the length and width in centimeters, then multiply the two numbers to get the square centimeters of one side. Multiply that number by 0.3A to estimate the current demand of the cell using a single cathode.

Also, if using two cathode plates (on opposite sides of the anode) then double the calculated Amps to figure the current demand of your cell.

Run lower current for your perchlorate cell than is used for the chlorate cell. I had success running perchlorate cells at 0.1 to 0.2 Amps per square centimeter.

I subscribe to the notion of using MMO for chlorates and either platinum or beta-form lead dioxide anodes for perchlorates.

WSM

 

 

To be clear, if my goal is potassium chlorate, I use potassium chloride electrolyte.

 

If my goal is potassium perchlorate, I start with sodium chloride, make sodium chlorate then make sodium perchlorate and finally potassium perchlorate. This is a very simplistic description without mentioning the various purification steps along the way. I find that taking the sodium route to KClO₄ is the most productive method without stressing my expensive and hard-to-find perchlorate anodes.

 

WSM

Edited November 6, 2020 by WSM

[rogeryermaw]

this is the part that trips me up. you know the strength of the sodium emission. for a lot of processes that is fine (rockets, salutes etc.) but for color stars it could be a problem. purification and recrystallization always cost some amount of product yield. how hard is it to fully eliminate sodium from the final product? also, i (guess i should do some research) am under the impression that most sodium salts are more hygroscopic than their potassium counterparts. is this true for perchlorate?

[Arthur]

Literature on the professional process indicates that the KCl should be added as a solution and the temperature, saturation and agitation of the mixing have effects on the crystal growth and the amount of sodium salt entrained in the precipitating potassium salt. Yes it's likely that washing the product would separate some sodium salt but it's not waste as with care what's left after removal of product simply goes back into feedstock for the process. The down side of recycling everything is that sooner or later even impurities from the cell start to build up. Then sulphates etc have to be removed. First you take all the chlorate out and recycle the chlorides (etc) then you take the perc out as K salt and recycle all the lower oxy chlorine products.

 

It's difficult to remove the last of the chloride from a cell by total electrolysis because the decreasing ion content get's harder and harder on the electrodes.

[rogeryermaw]

at some point, i imagine impurities will get to the point that your electrolyte must be discarded. how would you go about neutralizing such a chemical nightmare for disposal? or would you take it to a hazmat disposal center?

[Arthur]

Which is why WSM is careful to purify ingredients and use pure (RO ?) water etc.

 

The whole point is to work very cleanly so that waste that can be is fed back into the process, and waste that cannot be reused is minimised prior to disposal which should be neutralisation prior to disposal.

[WSM]

this is the part that trips me up. you know the strength of the sodium emission. for a lot of processes that is fine (rockets, salutes etc.) but for color stars it could be a problem. purification and recrystallization always cost some amount of product yield. how hard is it to fully eliminate sodium from the final product? also, i (guess i should do some research) am under the impression that most sodium salts are more hygroscopic than their potassium counterparts. is this true for perchlorate?

Absolutely.

 

WSM

Edited November 7, 2020 by WSM

[rogeryermaw]

swear i'm not trying to derail anything here and it is likely this is not well known here... i have always had my curiosities about electrolysis of various compounds and anyone who has been here a while knows what got me started in pyro.

 

i have long wanted to experiment with copper chlorate. it can be made with a simple ion exchange but the low solubility of barium chlorate is prohibitive in that gallons of reaction solution would have to be processed to obtain useful amounts.

 

given Mumbles' background in advanced chemistry, he may know this off the hop, but is it possible to make copper chlorate from a solution of copper chloride? (by electrolysis of course...derp)

Edited November 6, 2020 by rogeryermaw

[SeaMonkey]

It is known that Copper Salts tend to Electroplate when electrolyzed.

 

Would a mixture of Calcium Chlorate and Copper Sulfate precipitate Calcium Sulfate?

[WSM]

this is the part that trips me up. you know the strength of the sodium emission. for a lot of processes that is fine (rockets, salutes etc.) but for color stars it could be a problem. purification and recrystallization always cost some amount of product yield. how hard is it to fully eliminate sodium from the final product? also, i (guess i should do some research) am under the impression that most sodium salts are more hygroscopic than their potassium counterparts. is this true for perchlorate?

 

 

Where sodium chloride and potassium chloride solubilities are nearly equal, sodium oxy-chloride salts grow more soluble as the oxygen count goes up, and potassium oxy-chloride salts grow less soluble as the oxygen numbers increase. For example, sodium perchlorate is about 100 times as soluble as potassium perchlorate.

 

When potassium chloride solution is poured into purified (chlorate-free) sodium perchlorate solution (all at STP [standard Temperature and Pressure]), fine powdered potassium perchlorate instantly drops out of solution, making the originally clear starting liquids look opaque white.

 

The newly formed KClO₄ is then separated from the clear liquid residue by vacuum filtration (search Buchner funnel and vacuum filtration) and then the process of removing sodium contamination begins. Over four years ago, I found that simply rinsing the potassium perchlorate powder (in the Buchner funnel) with distilled water while the vacuum was still running, was inadequate for total (soluble) sodium contaminant removal.

 

My research has been on hold since then, but my thoughts are that repeatedly soaking the fresh perchlorate crystals in a volume of chilled distilled water followed by vacuum filtration, can dilute the sodium residue to imperceivably small amounts (essentially sodium free). I still need to try this. If I do, I'll report the results in this thread.

 

WSM

Edited November 7, 2020 by WSM

[WSM]

It is known that Copper Salts tend to Electroplate when electrolyzed.

Would a mixture of Calcium Chlorate and Copper Sulfate precipitate Calcium Sulfate?

 

 

Likely, yes; but the production of calcium chlorate by electrolysis sounds hazardous.

 

I seem to recall something about calcium chlorate being sensitive or dangerous when dry (perhaps it was calcium chlorate contamination of potassium chlorate)?! The traditional method of producing Ca(ClO₃)₂ was by bubbling chlorine gas (!) through calcium hydroxide solution, then filtering and drying the product. I haven't researched the nature and characteristics of calcium chlorate.

 

I don't know the solubility of barium chlorate, but calcium is in the same period of the periodic table and calcium chlorate may be similarly soluble (more or less). I would research this further before deciding on following a course of action...

 

Safety First.

 

WSM

[royster]

Quick question.

 

I ran a saturated solution of sodium chloride on 5volt and about 8A average for 6 full days, it was about 750ml and 1x4 inch platinized titanium anode and cathode, then i filtered it, boiled it to about 300ml (too much i think). I then added to it about 500ml of saturated potassium chloride solution, it started precipitating instantly, left it in the fridge for about 2 hours, filtered it off, re crystallized it and filtered at around 40c. I ended up with 220g of small white crystals.

 

What did i end up with? Lol

 

I got methylene blue coming in the mail i couldnt wait im doing things a55 backwards

[Arthur]

Methylene Blue is available here from aquarium shops. IIRC it cures some fish diseases.

[WSM]

Quick question.

I ran a saturated solution of sodium chloride on 5volt and about 8A average for 6 full days, it was about 750ml and 1x4 inch platinized titanium anode and cathode, then i filtered it, boiled it to about 300ml (too much i think). I then added to it about 500ml of saturated potassium chloride solution, it started precipitating instantly, left it in the fridge for about 2 hours, filtered it off, re crystallized it and filtered at around 40c. I ended up with 220g of small white crystals.

What did i end up with? Lol

I got methylene blue coming in the mail i couldnt wait im doing things a55 backwards

 

"Small white crystals" makes me think sodium chloride, or at best some sodium chlorate (but I am kind of doubting it. I hope I'm wrong!).

 

Methylene blue tests for perchlorates, and won't turn purple unless they are there.

 

WSM

[WSM]

Methylene Blue is available here from aquarium shops. IIRC it cures some fish diseases.

Hi Arthur,

 

Is that a solution or in the powdered form?

 

WSM