making potassium (per) chlorate

[taiwanluthiers]

Well, I do have white T shirts, just not ones that I want to throw away.

[Arthur]

http://www.ebay.co.uk/itm/Camlab-262-150mm-15cm-equiv-Whatman-GF-D-Filter-Circles-Pk25-Laboratory-Lab-/380714371285?pt=UK_BOI_Medical_Lab_Equipment_Lab_Supplies_ET&hash=item58a45848d5

 

Glass fibre filter circles.

[WSM]

http://www.ebay.co.uk/itm/Camlab-262-150mm-15cm-equiv-Whatman-GF-D-Filter-Circles-Pk25-Laboratory-Lab-/380714371285?pt=UK_BOI_Medical_Lab_Equipment_Lab_Supplies_ET&hash=item58a45848d5

Glass fibre filter circles.

 

The glass filter "paper" is a good suggestion. I wonder if a tight-weave fiberglass cloth (as used for resin-glass repairs) would work?

 

WSM

[WSM]

Well, I do have white T shirts, just not ones that I want to throw away.

 

There may be other inexpensive sources for used white cloth to use for filtering. Maybe you could expand your search, locally?

 

WSM

[WSM]

I'm putting the finishing touches on my Homegrown Oxidizers Part 5 article for publication in the next PGI Bulletin.

 

The article is about continuous potassium chlorate production, and is mainly the theory of the process, plus requisite materials and components. Article number 6 will address the practical aspects of building, setting up, running and fine-tuning a continuous system.

 

I'll try to get a blog started based on these articles, before long. Thanks for your patience.

 

WSM

[WSM]

No idea what the red stuff and the bag doesn't say. The problem is when I top up with fresh solution is that the process consumes chlorides faster than the water, so I'm basically doing this until the water overflows yet the solution is still depleted. I still need to add the salt to the solution without increasing its volume.

I have taken to filtering with colander and old T shirts, because it's faster and more efficient, and I don't need to burn up my vacuum cleaner trying to suck fluids through a funnel... the problem is the dye somehow gets bled into the solution, but the cell reaction ends up bleaching it off...

There are several ways to get the light vacuum needed to vacuum filter materials in a lab setup. One of the easiest is a water aspirator (try a google search). The one drawback to using the water aspirator the "traditional way" (running the water from a spigot, and down the drain) is the waste of water.

 

A way to overcome this problem is to set up a water pump and a closed loop water circulator in a bucket. That way you switch it on, it draws a vacuum and no water is wasted. Neat and tidy.

 

Cheers.

 

WSM

Edited June 2, 2014 by WSM

[taiwanluthiers]

it's not needed, though the fiberglass cloth idea seems good.

 

I managed to filter and recrystalize the KCl by using the same 1 liter of solution. I would boil it, dissolve the salt, filter, cool, decant the solution, boil, add salt, filter, repeat. I can get really clean salts this way.

 

By the way I noticed a weird phenomenon. I dissolved KCl in the cell liquor the other day and filtered it. Then I ran the cell. The cell ran for about 2 days but was full of loose crystals rather than tightly packed crystals I would normally get. I wonder what happened? I washed and cleaned the cell out but the yield wasn't all that great (about 200 grams maybe). It ran from 15 amps at the start to about 11 amps 2 days later. I also noticed fine black specks in the chlorate cell but there appears to be no change in the MMO. I wonder is the titanium cathode nearing the end of its life?

[Mumbles]

There was a seperate thread he openend Bout a month ago.

Where he mentions that it is a somewhat waxy stuff floating on top of his cell liquer like an oil

 

So never then?

[Mike]

So never then?

I think he meant about a month ago, where the red stuff got described as waxy and turns into an oil which floats on top of his cell.

Taiwanluthiers asked there for help and got some god answers.

Now he asked here again.

[taiwanluthiers]

I never said it turned into oil, I just said the red stuff feels a bit waxy and seems to float a bit. However upon further examination the red stuff is still somehow suspended throughout the solution and decanting doesn't seem to be an effective way to get rid of it.

[oldmanbeefjerky]

hi all. I recently realized that i have no hobbies, no real ones where i acomplish anything much anyway, it seems ide much rather spend my free time procrastinating between work and sleep, rather than doing what i want, mostly since its so hard, inspite of the rewards, so i got to thinking, why not start up the whole pyro thing again, that was way fun, but im going to need more chlorate and my last cell went missing. While im in the process of building it, i may was well build a proper decent cell, none of that improvised temporary nonsense, i still have 5kg of chloride left which i intend to make use of. Anyways.

I cant seem to find any regular PVC in the size/fittings i need, but there is uPVC, given that it is unplasticized and therefore contains no additional additives and such, will it work as well as regular white, PVC? warping wont be an issue given what i have planned.
the lid and bottom are UPVC, however, the mid section of the cell is still pvc pipe. Incase its at all relevant, my chlorate cell is like a pvc bucket with a screw lid. so upvc end cap base, pvc pipe mid section and upvc lid and threaded fitting.

 

so, i shouldnt have any problem right?

[WSM]

hi all. I recently realized that i have no hobbies, no real ones where i acomplish anything much anyway, it seems ide much rather spend my free time procrastinating between work and sleep, rather than doing what i want, mostly since its so hard, inspite of the rewards, so i got to thinking, why not start up the whole pyro thing again, that was way fun, but im going to need more chlorate and my last cell went missing. While im in the process of building it, i may was well build a proper decent cell, none of that improvised temporary nonsense, i still have 5kg of chloride left which i intend to make use of. Anyways.

I cant seem to find any regular PVC in the size/fittings i need, but there is uPVC, given that it is unplasticized and therefore contains no additional additives and such, will it work as well as regular white, PVC? warping wont be an issue given what i have planned.

the lid and bottom are UPVC, however, the mid section of the cell is still pvc pipe. Incase its at all relevant, my chlorate cell is like a pvc bucket with a screw lid. so upvc end cap base, pvc pipe mid section and upvc lid and threaded fitting.

so, i shouldnt have any problem right?

I suppose it depends on how you do it. The PVC without plasicizers sounds like regular hard PVC (plasticizers are often process oils that make the polymer "rubbery").

 

Do you have dimensions you can share? Inside and outside diameters plus wall thicknesses are helpful (certainly better than us all guessing what your materials are like!). Thanks.

 

WSM

Edited June 3, 2014 by WSM

[WSM]

I submitted the draft for Part 5 of the series on Homegrown Oxidizers, this morning. If you're a current PGI member, look for it in the pre-Convention issue.

WSM

Edited June 3, 2014 by WSM

[oldmanbeefjerky]

well, my parts are 150mm upvc in standard thickness, varying from 3.5-6mm thick between parts. itle be the same as my last cell which worked famously, only difference is that its uPVC.

 

given the lack of plasticizer could i asume that it would be less prone to warping from heat? in any case im going to take measures to prevent warping but still.

[WSM]

well, my parts are 150mm upvc in standard thickness, varying from 3.5-6mm thick between parts. itle be the same as my last cell which worked famously, only difference is that its uPVC.

 

given the lack of plasticizer could i asume that it would be less prone to warping from heat? in any case im going to take measures to prevent warping but still.

So what is the ID of the pipe and the height? It's easier to calculate the volume of the cell with the right information.

 

As for the UPVC, I've got no information about it, nor any experience with it. Your description, so far, makes it sound like thin walled pipe.. Can you post a photo of the parts you're describing? Thanks.

 

WSM

Edited June 3, 2014 by WSM

[oldmanbeefjerky]

ill take some photos later, but, its 150mm pvc pipe with upvc fittings, so the ID of the cell, of the pipe, would be 150mm, the height however, i am still thinking about, but i think 30cm seems reasonable. basically i just want it just deep enough that theres little chance of chlorate precipitating and building all the way up to the electrodes. the inner dimensions of the cell i guess would just be that of the pvc pipe, since the fittings just go around/ontop of it.

the pipe though will be regular pressure pipe. since the ID of the fittings is 16cm, i can only asume the pipe will have a thickness of 4-5mm

[WSM]

ill take some photos later, but, its 150mm pvc pipe with upvc fittings, so the ID of the cell, of the pipe, would be 150mm, the height however, i am still thinking about, but i think 30cm seems reasonable. basically i just want it just deep enough that theres little chance of chlorate precipitating and building all the way up to the electrodes. the inner dimensions of the cell i guess would just be that of the pvc pipe, since the fittings just go around/ontop of it.

the pipe though will be regular pressure pipe. since the ID of the fittings is 16cm, i can only asume the pipe will have a thickness of 4-5mm

 

Okay, so the maximum volume will be ~5.3 liters (pi x r² x h). With the added information, I'll guess it's about sched. 20 or 40 PVC (or is that UPVC?). I have a length of 6" thin wall PVC that sounds roughly equivalent to the pipe you're describing. With 1/4" PVC plate (sheet), it makes a decent cell.

 

Where in the cell do you place the electrodes? I ask because if it's in the upper portion of the cell, you'll get thermal layering in your cell (hot liquor in the top end and cool below) unless you stir things by some means. If the electrodes are in the lower portion of the cell, good mixing will occur due to "hydrogen lift" off the cathode(s); but beware of crystals shorting the electrodes if they reach them.

 

If you can draw us a picture of your cell (either verbally, sketch a drawing or take a photo), we can offer worthwhile suggestions !!!

 

WSM

[Mumbles]

While you're working on getting all your supplies together, you might also want to work on getting your spelling and capitalization together as well.

 

Most PVC pipe is actually measured by the OD, and given a nominal size for the ID. The ID will probably be in the ballpark of 150mm though. At least schedule 40 and 80 PVC will be 168mm OD. I believe the stuff sold for sewer pipes is smaller in the OD.

[oldmanbeefjerky]

ive already given it considerable thought on how i intend to construct my cell.

 

The electrodes will just hang from the lid and resemble an upright chlorinator cell, two cathodes, one anode, standard jar style setup.
The lid will have a tube comming from it, for venting gas, and possibly another, for bubbling air directly below the electrodes, or to put some titanium wire through so only the tip is exposed .

 

im still deciding about wether to be using hydrogen, or air, for generating bubbles to provide some flow, to stop the chlorate creeping up to the electrodes.

With hydrogen, there wouldnt be much gas flow since im using wire, unless i can bond one of my pool chlorinator cathodes to one of the two main cathodes, but it would be fairly easy to set up, while with air, ill need to use a pump, which i already have, but ide rather not use it since it makes the whole setup bigger and introducing air might cause more chlorine to diffuse from the water in the cell.

 

ill probably also mount a fan on or near the lid.

 

and beyond that ill trick the thing out with whatever i have laying about, like tempurature control and whatnot.

[WSM]

well, my parts are 150mm upvc in standard thickness, varying from 3.5-6mm thick between parts. itle be the same as my last cell which worked famously, only difference is that its uPVC.

given the lack of plasticizer could i asume that it would be less prone to warping from heat? in any case im going to take measures to prevent warping but still.

 

I'm not sure about UPVC, but PVC is rated to 60^oC, but Swede commented once that the temperature was for a rated pressure. Since we're operating at ~1 atmosphere, it can probably safely handle more heat without deformimg.

 

Keep an eye on it in any case...

 

WSM

[WSM]

ive already given it considerable thought on how i intend to construct my cell.

The electrodes will just hang from the lid and resemble an upright chlorinator cell, two cathodes, one anode, standard jar style setup.

The lid will have a tube comming from it, for venting gas, and possibly another, for bubbling air directly below the electrodes, or to put some titanium wire through so only the tip is exposed .

im still deciding about wether to be using hydrogen, or air, for generating bubbles to provide some flow, to stop the chlorate creeping up to the electrodes.

With hydrogen, there wouldnt be much gas flow since im using wire, unless i can bond one of my pool chlorinator cathodes to one of the two main cathodes, but it would be fairly easy to set up, while with air, ill need to use a pump, which i already have, but ide rather not use it since it makes the whole setup bigger and introducing air might cause more chlorine to diffuse from the water in the cell.

ill probably also mount a fan on or near the lid.

and beyond that ill trick the thing out with whatever i have laying about, like tempurature control and whatnot.

 

I noticed that when I bubbled air in a 3 liter cell (using an aquarium air pump) that the cool air caused the end of the tube to jam with chlorate crystals. One solution to this problem: run a coil of the air tubing in a hot water bath (to heat the air being fed to the bubbler) before it runs into the cell. Perhaps the crystal jamming will stop.

 

Also, for safety, be sure the fan near the top of the cell is non-sparking (wouldn't want the hydrogen to explode and mess up the cell)!

 

WSM

[WSM]

it's not needed, though the fiberglass cloth idea seems good.

I managed to filter and recrystalize the KCl by using the same 1 liter of solution. I would boil it, dissolve the salt, filter, cool, decant the solution, boil, add salt, filter, repeat. I can get really clean salts this way.

By the way I noticed a weird phenomenon. I dissolved KCl in the cell liquor the other day and filtered it. Then I ran the cell. The cell ran for about 2 days but was full of loose crystals rather than tightly packed crystals I would normally get. I wonder what happened? I washed and cleaned the cell out but the yield wasn't all that great (about 200 grams maybe). It ran from 15 amps at the start to about 11 amps 2 days later. I also noticed fine black specks in the chlorate cell but there appears to be no change in the MMO. I wonder is the titanium cathode nearing the end of its life?

 

When I first ran a cell with MMO, I used a one gallon, thick-walled polyethylene, wide-mouth jar for the cell. Without pH control (running alkaline), I got fine black specks in the chlorate formed. Research showed that PE polymers break down in a strong alkaline environment.

 

I changed the cell body to a one gallon (3.785 liter) glass pickle jar with a 4" PVC pipe cap for a lid, and the problem dissappeared.

 

If your cathodes are wearing, what sort of condition do they appear to be in? I'd expect pitting and some type of corrosion. Let us know (or better, post a photo). Thanks.

 

WSM

Edited June 5, 2014 by WSM

[Arthur]

pH control may be more important than we first thought. While pH has effects on the current efficiency of the cell, it also has effects on the degradation of the cell wall (etc). A strong chlorate solution may oxidise, but a strongly basic solution will add lots of other degradation mechanisms. A cell using a glass vessel and some of Swede's electrodes died suddenly and it seemed that there were traces of electrolysed silicates (from the glass) plated onto the electrodes.

 

IMO when using a glass vessel pH control may be essential not just an option.

[taiwanluthiers]

I am using PP container and have not experienced any erosion of the container. Just use whatever they use to put bleach into because that's essentially what a non PH controlled cell is...

[WSM]

pH control may be more important than we first thought. While pH has effects on the current efficiency of the cell, it also has effects on the degradation of the cell wall (etc). A strong chlorate solution may oxidise, but a strongly basic solution will add lots of other degradation mechanisms. A cell using a glass vessel and some of Swede's electrodes died suddenly and it seemed that there were traces of electrolysed silicates (from the glass) plated onto the electrodes.

IMO when using a glass vessel pH control may be essential not just an option.

All very good points, Arthur. I did run my pickle jar cell w/o pH control and noticed no problems. I ran it with distilled water plus KCl, and used a regulated power supply, and never saw any degradation of the electrodes or glass jar.

 

But, like you, I'm inclined to agree that pH control is beneficial for more than just current efficiency (CE).

 

WSM

Edited June 7, 2014 by WSM