making potassium (per) chlorate

[pyrojig]

excited to read it when your done .!! I too have suffered a overly heavy work load and feel bad I have not been able to contribute to the thread in a very long time . I miss the innovative minds at work here . I should be slowing down this winter a bit , and may be able to chime in on some experience or questions . WSM , please do keep me updated on the next additions your writing . I would like to add it to the collection as well as see your latest work.

[WSM]

I've started a purification experiment with potassium chloride. I want to see if purifying the KCl (water softener salt) works as well as it did with the sodium chloride salt used to make brine for the sodium cell experiment.

 

I used the second large brine tank and put in a 50 pound container-full (plus a bit more) of KCl water softener salt, and then added 12 gallons of distilled water (it needed 17 gallons but twelve was all I had on hand) and started the circulation pump about 7 PM two days ago.

 

The goals of this experiment are:

1. dissolve the KCl salt to roughly 350 grams per liter of pure water
2. filter out any insolubles or solid debris
3. treat the clear filtrate with potassium carbonate solution to precipitate any dissolved contaminates
4. let the cloudiness settle and then decant the clear liquid, plus filter out the precipitate
5. test the pH of the filtrate and if it's alkaline (as expected), neutralize it with HCl
6. store the purified KCl brine in a sealed container for later use

The purified potassium chloride brine can either be electrolyzed to potassium chlorate or used to react with other pure salt solutions to make pure potassium salts.

 

WSM

Edited October 14, 2017 by WSM

[WSM]

I was tired of looking at undissolved crystals on the bottom of the brine tank, so I bought and added six more gallons of distilled water.

 

A few days later all the crystals were dissolved and I could clearly see the debris on the bottom of the tank.

 

The next step is to filter the course contaminants out before treating the clear solution to remove unseen contaminants.

 

I'll post more later.

 

WSM

[WSM]

I should mention that my original calculation was for 17 gallons of water in 50 pounds of KCl to make up a stock solution of potassium chloride (350g/l), but since I added more KCl, the extra gallon was needed. I'll try to take more photos so you can see what I'm seeing.

 

More later...

 

WSM

[WSM]

I just submitted Homegrown Oxidizers Part 17 to the PGI for printing in their December-January bulletin. The subject varies from making oxidizers to purification of precursor, process and final product chemicals.

 

I feel the subject is important enough to dedicate an article or two to it. We may be happy just to be able to make our own oxidizers, but since we're going to the trouble to do so, why not make the effort to make them as pure as (or even purer than) commercial oxidizer salts?

 

I hope to cover this topic better in the future; maybe even start a separate thread covering purification of chemicals. It would greatly increase safety for amateurs, as well as offer an improvement to color depth and clarity of stars, too.

 

Any thoughts?

 

WSM

Edited November 18, 2017 by WSM

[WSM]

Sorry I've been so quiet lately. I've been very busy at work plus building a new workshop.

 

I have a lot more work to do on the workshop before it's ready to utilize properly, but I've got great plans for it.

 

My wife doesn't mind if I have stuff; she just doesn't want to see it , so into the shed (workshop) it goes!

 

I'll get back to my experiments after the dust settles...

 

WSM

[PTFE]

hey guys, merry Christmas!

Im very busy at the moment so i cant give you much details, but i will give you more information soon.

The 5V300A PSU is almost finished and i started to work out the plan for the cell.

 

 

 

 

Everything will be made out of Ti Gr2 . The sheets i've got are 2mm thick, i also have a bunch of M8 bolts so maybe no welding is reqired.

The smalest conductor will be 100mm²Ti (50x2x--) for the conection of each electrode.

 

I also have an d=20mm Ti Gr2 Rod. The cross-section is 314mm² so maybe i could figure out a way to conect it to the busbar in the Cell for easy feed-through.

Edited December 26, 2017 by PTFE

[Simoski]

Hey Guys, Merry Christmas.

 

I find it strange that no one makes cell arrays...

 

My setup is 3 10l MMO Ti cells in series running off an inexpensive 12v 20amp power supply. That's 20amps through each cell so 60 amps production in total. 12 volt supplies are very common, 5/6 not so much. ( Well here in South Africa anyway ).

 

Have any of you built arrays?

[Simoski]

I just submitted Homegrown Oxidizers Part 17 to the PGI for printing in their December-January bulletin. The subject varies from making oxidizers to purification of precursor, process and final product chemicals.

 

I feel the subject is important enough to dedicate an article or two to it. We may be happy just to be able to make our own oxidizers, but since we're going to the trouble to do so, why not make the effort to make them as pure as (or even purer than) commercial oxidizer salts?

 

I hope to cover this topic better in the future; maybe even start a separate thread covering purification of chemicals. It would greatly increase safety for amateurs, as well as offer an improvement to color depth and clarity of stars, too.

 

Any thoughts?

 

WSM

I like the idea, like using alum as a flocculant to remove stearic acid binder from fertilizer grade chems...

[Arthur]

Simoski, Series stacks of cells are the commercial norm. Hobby wise there are few enough cells in production that there is no wisdom yet about balancing a series stack. There are probably no series cells except yours.

Edited December 26, 2017 by Arthur

[PTFE]

Hey Simoski

Your idea is very good. The industrial setup is the same. They use Cells connected in series to minimize the voltage drop and to save conductor material.

For me it was no option, because i don't like the idea of more than one cell.. Its the effort to make the cell as leakproof as possible which made the decision for me.

Another advantage of the idea of an array is, that you can carry the gases from the first cell through the second and the gases from the second cell through a third and so on. This will maximize your chlorine consumption and will lead to a better efficiency i think.

 

Something i thought about is a big tank with seperated cells in one tub, all immersed within the same Electrolyte but i don't know, how the currents will flow. Since the Resistance is quite high over a long distance, i think it will work quite well.

 

 

maybe i'll try it out in a very small scale 5x 50ml or so

Edited December 26, 2017 by PTFE

[WSM]

Hey Guys, Merry Christmas.

I find it strange that no one makes cell arrays...

My setup is 3 10l MMO Ti cells in series running off an inexpensive 12v 20amp power supply. That's 20amps through each cell so 60 amps production in total. 12 volt supplies are very common, 5/6 not so much. ( Well here in South Africa anyway ).

Have any of you built arrays?

 

I've considered it but haven't ventured to do so yet.

 

60 Amps is misleading. Actually, in series the voltage drops through each cell but the current is common throughout the system. The end result in a perfect world is each cell would get 4 Vdc and 20 Amps.

 

If you're able to, post photos of your setup. It would be interesting to see.

 

WSM

Edited December 26, 2017 by WSM

[WSM]

Simoski, Series stacks of cells are the commercial norm. Hobby wise there are few enough cells in production that there is no wisdom yet about balancing a series stack. There are probably no series cells except yours.

 

Possibly, but I wouldn't rule it out or be surprised to learn there are (or were) such systems out there.

 

WSM

[WSM]

Hey Simoski

Your idea is very good. The industrial setup is the same. They use Cells connected in series to minimize the voltage drop and to save conductor material.

For me it was no option, because i don't like the idea of more than one cell.. Its the effort to make the cell as leakproof as possible which made the decision for me.

Another advantage of the idea of an array is, that you can carry the gases from the first cell through the second and the gases from the second cell through a third and so on. This will maximize your chlorine consumption and will lead to a better efficiency i think.

Something i thought about is a big tank with seperated cells in one tub, all immersed within the same Electrolyte but i don't know, how the currents will flow. Since the Resistance is quite high over a long distance, i think it will work quite well.

xx.JPG

maybe i'll try it out in a very small scale 5x 50ml or so

 

An interesting idea. I like the idea of an experimental setup to determine the effect of ganged cells in a single chamber. Let us know if you set one up and the results.

 

WSM

[WSM]

hey guys, merry Christmas!

Im very busy at the moment so i cant give you much details, but i will give you more information soon.

The 5V300A PSU is almost finished and i started to work out the plan for the cell.

DSC_03921.JPG

DSC_03731.JPG

300A 20L.JPG

Everything will be made out of Ti Gr2 . The sheets i've got are 2mm thick, i also have a bunch of M8 bolts so maybe no welding is reqired.

The smalest conductor will be 100mm²Ti (50x2x--) for the conection of each electrode.

I also have an d=20mm Ti Gr2 Rod. The cross-section is 314mm² so maybe i could figure out a way to conect it to the busbar in the Cell for easy feed-through.

 

A belated Merry Christmas to all.

 

Wow, PTFE. That is a beast of a power supply! Please keep us up to date on the progress and how everything works out (nice work, by the way).

 

WSM

[Simoski]

Chaps I'm definitely gonna put the electrode assemblies into a large vat of electrolyte in a gang and do some voltage/current tests to see if they short each other out or if the current runs consecutively through each electrode assembly as with my current cell arrays.

 

Let me see if I can work out how to embed images...

[PTFE]

Thank you WSM

For my 300A Cell i will make a full documentary. Also the Building of the PSU will be documented.

In the meantime i will try out the idea of ganged cells, if i could get some Cheap MMO Mesh and some 5mm Ti-Rods.

 

 

My next step is, to bring the Ti-sheets ive got to a company which offers water-jet cutting to get all the small Sheets with holes I need for the connections in the cell.

Edited December 26, 2017 by PTFE

[Simoski]

I can get the MMO to you PTFE, there is an electrode manufacturing plant near me... going to sell their MMO and Pt coated titanium mesh on eBay, as soon as I get home from holiday that is.

 

And well done on making a 300A monster supply, is that a rewound MOT, rectifier, Variac and ammeter?

[Simoski]

Here two MMO, stainless electrode assemblies in series. This was a test with a 12volt 1amp supply just to make sure there were no shorts. Note the yellow colour from potassium dichromate additive. ( I'm sure you know that di/chromate ions reduce corrosion of stainless steel and prevent reduction of hypochlorite and chlorate ions at the cathode )

Later the electrode assemblies were moved to larger cell bodies.

 

 

Here a close up of one of the electrode assemblies, note that the cathodes are insulated with PVC heat shrink on the one side, this allows electrons to enter the cell from the bottom and provides a more even distribution of electrons across the surface of the anode. Note too how close the anode and cathode are to each other < 5mm, this reduces the internal resistance and allows more electrons to flow through the cell.

Edited December 26, 2017 by Simoski

[PTFE]

I can get the MMO to you PTFE, there is an electrode manufacturing plant near me... going to sell their MMO and Pt coated titanium mesh on eBay, as soon as I get home from holiday that is.

 

And well done on making a 300A monster supply, is that a rewound MOT, rectifier, Variac and ammeter?

Hey dude, Thanks alot for your offer!

Please let me know what the prices are for MMO mesh 0,5-1mm

 

My Powersupply is built based on a 225mm Fan.

On top of the fan two DC-DC switching supplys from Nemic Lambda (312Vdc->5Vdc150A) where mounted to be connected in parallel.

On top of the two SMPS sits a Rectifier rated at 1200V/50A along with 2000µF Smmoothing caps to provide the input voltage of 300Vdc and a bunch of other stuff you will see later in the full documentary

The Variac would be kinda small for handling ~2Kva. Its a 230V/1.4Amp Variac to control the fan Speed to keep the Supply as silent as possible in case of operating small cells with lower amperage.

 

The output Amperage will be measured with a LEM current transformer which is capable of handling currents from -300A_0_+300A by giving an output of -4V_0V_+4V.

This Voltage signal (wich will vary between 0-+4V in this application) will be converted by an U/I-converter to an 0-20mA signal.

This signal is then evaluated by the Amperemeter to an Number shown on the Display

 

your setup looks nice, i wish i had the opportunity to do it inside.

Don't you worrie about the gases and the chlorine?

 

edit:

My very first supply was an rewound MOT which gets much to hot and is to lossy for high power applications.

Since ive wound a very thick Secondary I used it for Spot welding of 1mm Ti because of its capability to deliver something around 700-800A when shorted.

 

The Nice thing about SMPS is, they are small and wheightless, silent, efficent and very powerfull but also more expensive.

Ive got mine for 160$ each, so its a rather expensive project.

But like WSM said pages ago, The Electrolysis is a great hobby with great fun, so i dont care much.

I could stay at my 100A Cell, but i want to know, whats the maximum an amateur could go with single phase power supplys.

Sure i could go much higher with three phase transformers but my limit is the handling of the electrolyte and 16L cell volume is quite a lot of stuff too treat.

Edited December 26, 2017 by PTFE

[PTFE]

Can someone give me some information if PVC tubing will withstand the cell environment?

I think about using aquaristic pvc-tubing for the cooling-spiral inside but i don't like the idea of an leak in the Tube, pumping the cooling water into the cell.

My 100A Cell uses a PTFE Tube as cooling tube but its to expensive for a large project like this

Edited December 26, 2017 by PTFE

[Simoski]

PVC is extremely resistant to chlorate electrolyte PTFE. Build away! Grab the PVC at any large hardware store and or plumbing supply shop. Maybe watch some videos on YouTube where guys partially melt the PVC tubing and turn then into recurve bows for an idea of how to shape it... https://youtu.be/lfeOcIagnD0

 

I added KOH to my cell before testing it so only H2 escaped. No Cl2 to worry about oxidising all the metal in the room. Only ran at 1 amp overnight then I put the 2 assemblies outside in their own 10l Perspex cell bodies.

 

What do LEM and SMPS stand for ?

 

As for pricing I can have it manufactured to size... Just need dimensions to get you a quote... Don't forget I live in South Africa so there will be shipping charges... Either way let's work it all out in the new year

Edited December 26, 2017 by Simoski

[PTFE]

PVC is extremely resistant to chlorate electrolyte PTFE. Build away! Grab the PVC at any large hardware store and or plumbing supply shop. Maybe watch some videos on YouTube where guys partially melt the PVC tubing and turn then into recurve bows for an idea of how to shape it...

 

I added KOH to my cell before testing it so only H2 escaped. No Cl2 to worry about oxidising all the metal in the room. Only ran at 1 amp overnight then I put the 2 assemblies outside in their own 10l Perspex cell bodies.

 

What do LEM and SMPS stand for ?

 

As for pricing I can have it manufactured to size... Just need dimensions to get you a quote... Don't forget I live in South Africa so there will be shipping charges... Either way let's work it all out in the new year

Lem is a company located in swizerland. They manufacture current transformers for high quality applications all around the world. They use the hall-effect to be capable to measure DC and high frequency currents.

The one i use is the LEM-HAS300-S

 

SMPS stands for Switched-Mode-Power-Supply.

 

For cooling i like to use the standard Aquaristic tube inside the cell

http://i.ebayimg.com/images/g/Z7kAAOxyzi9SioJG/s-l300.jpg

Since i´ve used it for venting my first cells i´ve noticed, they became much harder after some chlorine exposure.

Maybe someone with a running cell can insert a pice of PVC-tube for a resistantce test.

[Arthur]

Rigid PVC is resistant to the cell fumes, and will last a long while. Soft PVC is less resistant to cell fumes and may need frequent replacement.

[MrB]

Something i thought about is a big tank with seperated cells in one tub, all immersed within the same Electrolyte but i don't know, how the currents will flow. Since the Resistance is quite high over a long distance, i think it will work quite well.

 

I'm not sure it makes any sense to put them in separated cells. At the most you need a inert plastic barrier between the cathode and the next anode, but in reality i think you would get away with just spacing them appropriately. But you would need a means of conductive connecting point to tie the par together, and something none conductive between the working pair... I'm thinking plastic, and titanium, bolts, and spacers. Main issue. Making holes in the anode without damaging them more then you have to, and then not damaging them when bolting it together...