making potassium (per) chlorate

[WSM]

My research will be on hold for a while. I'm leaving to visit family for two weeks and when I get back, work is going to be super busy till the beginning of November. I'll see if I can do something in between but it'll be difficult till work gets back to normal.

 

I'll still read and post here, but my active research will be on the back burner till things calm down.

 

WSM

Edited September 30, 2016 by WSM

[greenlight]

@ WSM, thankyou for the replies..

 

So, I run the sodium chloride to chlorate with MMO anode, recharge cell and run again before switching to the PT anode and continuing to perchlorate.

I will use a larger 2-3 litre cell like you said instead of a small 1 litre cel.

Then I remove as much chlorate as possible before mixing with a sat. potassium chloride solution.

 

I will upload a photo of my previous tiny cell when I get a chance.

 

Is there any definite calculations for how long it will take to get a high concentration of NaClo3 from the NaCl using 5v 20 amp? There was a page I found a long time ago but I can't find it again.

Edited September 30, 2016 by greenlight

[WSM]

@ WSM, thankyou for the replies..

So, I run the sodium chloride to chlorate with MMO anode, recharge cell and run again before switching to the PT anode and continuing to perchlorate.

I will use a larger 2-3 litre cell like you said instead of a small 1 litre cel.

Then I remove as much chlorate as possible before mixing with a sat. potassium chloride solution.

I will upload a photo of my previous tiny cell when I get a chance.

Is there any definite calculations for how long it will take to get a high concentration of NaClo3 from the NaCl using 5v 20 amp? There was a page I found a long time ago but I can't find it again.

Don't forget to destroy residual chlorate before converting the sodium perchlorate to potassium perchlorate. I've had success using sodium metabisulfite solution and inject it slowly, deep under the surface of the electrolyte.

 

I've got a link to a runtime calculator, but it's on my computer back home and I'm on my smartphone while traveling.

 

WSM

[greenlight]

The destruction of residual chlorate is one thing I still have to figure out properly.

 

I have brought a 2.25 litre container for the perchlorate cell and everything is ready to go except I am waiting on some large alligator clips to replace the small ones I used before.

 

I had a go at working out the runtime using charts I found on a chlorates and perchlorates page on google: http://www.oocities.org/capecanaveral/campus/5361/chlorate/runtime.html

 

I have calculated that I can get about 807 g sodium chloride into the new size cell water.

The runtime for chloride to chlorate I have calculated for 5 volt 20 amp power supply at 54% efficiency using the chart to be:

 

807.75-(100×2.25)×15.27 = 2628 mins or 43.8 hours at 54% current efficiency.

or 64.05 hours at 40% current efficiency.

 

At this stage I will swap to the platinum coated anode.

 

From the same webpage and calculating runtime to convert 86% of the chlorate to perchlorate at 50% current efficiency:

 

2090.92 mins or 34.85 hours

 

Does this seem right as I have never had to calculate because I usually only run KCl to KClo3?

 

I have attached a picture of the old and new setup. On the left is the old 1L chlorate cell with MMO and Ti electrodes and on the right is the new 2.25L cell container with MMO and Ti electrodes and a Pt coated anode.

Edited October 4, 2016 by greenlight

[WSM]

The destruction of residual chlorate is one thing I still have to figure out properly.

I have brought a 2.25 litre container for the perchlorate cell and everything is ready to go except I am waiting on some large alligator clips to replace the small ones I used before.

I had a go at working out the runtime using charts I found on a chlorates and perchlorates page on google: http://www.oocities.org/capecanaveral/campus/5361/chlorate/runtime.html

I have calculated that I can get about 807 g sodium chloride into the new size cell water.

The runtime for chloride to chlorate I have calculated for 5 volt 20 amp power supply at 54% efficiency using the chart to be:

807.75-(100×2.25)×15.27 = 2628 mins or 43.8 hours at 54% current efficiency.

or 64.05 hours at 40% current efficiency.

At this stage I will swap to the platinum coated anode.

From the same webpage and calculating runtime to convert 86% of the chlorate to perchlorate at 50% current efficiency:

2090.92 mins or 34.85 hours

Does this seem right as I have never had to calculate because I usually only run KCl to KClo3?

I have attached a picture of the old and new setup. On the left is the old 1L chlorate cell with MMO and Ti electrodes and on the right is the new 2.25L cell container with MMO and Ti electrodes and a Pt coated anode.

When you run the sodium chlorate cell; after the first run, the sodium chlorate is at half the concentration required for a perchlorate cell. The chlorate electrolyte should be recharged with chloride and run again to boost the chlorate level to at least 600g per liter for a proper perchlorate electrolyte.

 

I decided to run my sodium chlorate cell over and over, and harvest crystalline sodium chlorate as part of the purification process; before making new electrolyte from it with distilled water, for the perchlorate cell.

 

WSM

Edited October 7, 2016 by WSM

[greenlight]

 

Thankyou for your help.

So I can either run it multiple times and crystallise out the solid sodium chlorate to make a new electrolyte or run for the time required to make chlorate once, recharge with salt and run again for the same amount of time before changing the anode to a Pt one?

Edited October 7, 2016 by greenlight

[Arthur]

Take a saturated chloride electrolyte, pass current for about 60% completion, add 50% of the chloride salt that you first added, pass current again (60% completion amp hours) add another 50% of the amount of chloride that you first used, electrolyse that lot.

 

As the chloride content goes down by conversion to chlorate the current efficiency goes down and electrode damage goes up.

[WSM]

Thankyou for your help. So I can either run it multiple times and crystallise out the solid sodium chlorate to make a new electrolyte or run for the time required to make chlorate once, recharge with salt and run again for the same amount of time before changing the anode to a Pt one?

Perchlorate cells are happiest with high chlorates and low chlorides. Whatever you do, see if you can achieve those conditions and you'll be okay.

 

WSM

[WSM]

Take a saturated chloride electrolyte, pass current for about 60% completion, add 50% of the chloride salt that you first added, pass current again (60% completion amp hours) add another 50% of the amount of chloride that you first used, electrolyse that lot.

As the chloride content goes down by conversion to chlorate the current efficiency goes down and electrode damage goes up.

This sounds like a good idea to get the chlorate levels as high as possible. Keeping the chloride level up as you make chlorates is always a good idea.

 

As attractive as it sounds to run directly from sodium chloride to sodium perchlorate, most successful perchlorate makers do in two steps; first chlorate and then perchlorate.

 

WSM

[Arthur]

MY aim would be to electrolyse chloride, adding more chloride as the reaction progresses, until there is approximately a saturated solution of chlorate with some chloride.If you chill this lots of chlorate should ppt out as nice crystals ready to be redissolved in minimal water for electrolysis in a separate cell to perc then you can ppt out the KPerc by adding saturated KCl solution. Every time you add KCl you can send the electolyte back to the chlorate cell to react the chloride to chlorate again.

 

You'd need to evaporate water off, or the electrolyte volume would increase, getting messy.

[greenlight]

Thanks for all the replies,I'm just waiting on some big alligator clips for the next cell and I will start.

I will run to 60% completion and recharge maybe 3 times and then go from there. Either crystallise the sodium chlorate or run the last chlorate cell for longer maybe 86% completion and turn it into a perc cell.

Will post results as they come.

Edited October 10, 2016 by greenlight

[Arthur]

Many of us would be satisfied with a chlorate cell, good chlorate is very usable -just chose the formulae carefully.

[greenlight]

I think I will have two seperate 2.25 L cells, one for chlorate and one for perchlorate.

 

One problem I have noticed is that Pt-coated anode is only half the size of the titanium cathode. Does this mean I can only insert the Ti cathode halfway into the solution so they are submerged at equal lengths or does it not matter?

[taiwanluthiers]

There aren't a lot of published chlorate formula because people fear them.

 

The few that are there burns REALLY fast. even a 3/8" star would burn out in less than .2 seconds and it's really unsuitable for shells, maybe as roman candles. It's also not very bright as well.

 

I'm sure Zambelli or others have secret chlorate formula that works really well for shells, burns bright, great colors, and burns at the right rate, but nobody knows what they are and they're trade secrets.

 

So a lot of experimentation is needed... ideally for a bright star that are green or red, you want metal fuel. I don't know how chlorate deals with metal fuel, however do not do a 1:1 substitution with perchlorate because both chemicals give out different amount of oxygen and reacts differently to different fuels or binders, so a substitution would make a very drossy and dirty star.

 

Perhaps for metal fueled carbonate based red or green, you will want to increase chlorate content, decrease chlorine donor (chlorate itself makes decent chlorine donor so you will not need as much parlon) and maybe make adjustment to the amount of metal fuel or strontium carbonate (in the presence of magnesium or magnalium strontium carbonate acts as an oxidizer, so it doesn't have much perchlorate to begin with)

Edited October 11, 2016 by taiwanluthiers

[OldMarine]

There's around 100 chlorate based formulas on Passfire. Most are organic fueled blues and purples but there are quite a few metal fueled ones in there as well.

[WSM]

Many of us would be satisfied with a chlorate cell, good chlorate is very usable -just chose the formulae carefully.

Chlorates are useful and powerful oxidizers. The most common chlorate used in pyrotechnics is potassium chlorate.

 

If unfamiliar with the character or nature of potassium chlorate, it's important to proceed slowly and cautiously until it's well understood. For safety, work with small amounts of material and on a small scale until you understand the potential of these materials.

 

It's tempting to scale up too soon, and this can get dangerous. Small accidents are easy to walk away from, but large ones; not so much. Be very careful when working with high energy mixtures and avoid incompatible combinations.

 

If unsure, ask.

 

WSM

[WSM]

I think I will have two seperate 2.25 L cells, one for chlorate and one for perchlorate.

One problem I have noticed is that Pt-coated anode is only half the size of the titanium cathode. Does this mean I can only insert the Ti cathode halfway into the solution so they are submerged at equal lengths or does it not matter?

The relative sizes of the electrodes is more critcal in industry where they work on a large scale, but less critical on a small, experimental scale.

 

I think you'll be okay with your mismatched electrodes in the small cell you plan to run. I imagine any inefficiency will be minimized due to the small scale you're operating at. Try it and see.

 

WSM

[WSM]

There's around 100 chlorate based formulas on Passfire. Most are organic fueled blues and purples but there are quite a few metal fueled ones in there as well.

There are lots of effective and beautiful effects possible using potassium chlorate. Learn about the hazards involved in using chlorates and proceed with caution.

 

Lots of good formulae can be found in the classic literature, as well as in sites like Fireworking. The books by Dr. Shimizu and Hardt are excellent references, too.

 

WSM

Edited October 11, 2016 by WSM

[greenlight]

Thankyou WSM, I will do that and post results thankyou for all you guys help here

[WSM]

Thankyou WSM, I will do that and post results thankyou for all you

 

I just re-read your post. Since we're talking about a sodium perchlorate cell, I might caution about using a power supply with constant current capability so the platinum anode will last longer.

 

If you limit the current to 0.2 Amps per square centimeter, I think the system should work okay.

 

WSM

[WSM]

There are lots of effective and beautiful effects possible using potassium chlorate. Learn about the hazards involved in using chlorates and proceed with caution.

Lots of good formulae can be found in the classic literature, as well as in sites like Fireworking. The books by Dr. Shimizu and Hardt are excellent references, too.

WSM

I should also mention, if you can find a copy of the Pyrocolor Harmony by Joel Baechle, it has a wealth of pyrotechnic color design information and many formulas, including chlorate star compositions.

 

WSM

[greenlight]

I will get the sodium chlorate cell recharged a few times to get a nice crop for the second perc step and figure it from there.

Is 5v 20 amp too much current for the perchlorate conversion with the Pt anode?

[WSM]

I will get the sodium chlorate cell recharged a few times to get a nice crop for the second perc step and figure it from there.

Is 5v 20 amp too much current for the perchlorate conversion with the Pt anode?

 

If your platinized titanium anode is about 5 cm x 8 cm, I figure the current demand (at 0.2 A / cm²) to be about 16 A, and should be fine. Good luck and let us know how it goes.

 

WSM

Edited October 13, 2016 by WSM

[WSM]

MY aim would be to electrolyse chloride, adding more chloride as the reaction progresses, until there is approximately a saturated solution of chlorate with some chloride.If you chill this lots of chlorate should ppt out as nice crystals ready to be redissolved in minimal water for electrolysis in a separate cell to perc then you can ppt out the KPerc by adding saturated KCl solution. Every time you add KCl you can send the electolyte back to the chlorate cell to react the chloride to chlorate again.

You'd need to evaporate water off, or the electrolyte volume would increase, getting messy.

 

This is a good, brief description of how it may be done. What might be unclear is why the electrolyte can be sent back to the sodium chlorate cell, after the metathesis with KCl.

 

When the (chlorate-free) sodium perchlorate solution is mixed with potassium chloride, potassium perchlorate is formed instantly, dropping out of the solution as fine, white crystals (almost powder, actually); and the resulting sodium chloride solution is left behind. If everything is done stoichiometrically, there should be very little, if any, potassium salts left; so in theory, Arthur's comment above is absolutely correct.

 

In practice, it may be trickier and messier than that, but it's possible. With the low cost of sodium salt, many amateur electrochemists would dispose of the perchlorate cell filtrate and start fresh by recharging the "depleted" sodium perchlorate cell liquor with more chloride and continue making more sodium chlorate with it.

 

Concentrating the NaCl solution by evaporating the surplus water, is a viable option; if the economy of it fits your circumstances. In a small cell it's certainly affordable, but if running a 100 liter monster cell, it can quickly get too expensive. To each their own...

 

WSM

Edited October 14, 2016 by WSM

[Arthur]

Dropping 50litres of weak chlorate into a small village sewage system would kill the bio activity and be very bad. the same 50l in a big urban drain system would be less of a problem.