Sciencemadness Discussion Board

Some basic questions and clarifications on NaCl chlorate cell and potassium chlorate

Junk_Enginerd - 30-7-2020 at 01:46

I've just got my first chlorate cell up and running. Bought a ~30x120 mm MMO anode from eBay and made a crude first prototype of a cell to see how it worked. Stainless steel wire as cathode distributed mostly evenly around the anode, with significantly smaller surface area than the anode as per recommendations. About 700 ml capacity.

I haven't yet found any source of pure KCl, so right now I'm running it with NaCl. I just did my first extraction and test of the chlorate and I'm a little disappointed. I'd appreciate some help on what step may have failed.

What I did was run the cell for about 5 days and 2 A, so 240 Ah. Should end up with 50-100 g of chlorate as I understand it. It's pretty consistently been at 3 V in case that's important, and I'd estimate the temp to have been about 40°C in the cell. I've topped up with NaCl along the way the keep it saturated.

In the end I want potassium chlorate. I managed to find a 60/40 mix of NaCl/KCl in the form of a salt substitute. Now, the way I understand the conversion of Sodium Chlorate to Potassium Chlorate is that Potassium Chloride is added to the solution of sodium -chlorate and -chloride, everything mixes up, and Potassium Chlorate being poorly soluble in water will precipitate. I only have the 60/40 mix, which leads me to:

Question #1: Instead of adding pure potassium chloride, should it not work equally well to add a saturated solution of my 60/40 salt? After all, the cell solution is already full of sodium chloride anyway, so it should not make much of a difference? This is what I did, and I did get a precipitate.

Question #2: As I was doing this, it seemed like a redundant step. Could I not just electrolyze the 60/40 salt as is, and let the reaction happens as the cell goes? Any sodium chlorate that forms should automatically react to potassium chlorate, and if potassium chlorate is formed, well, that's what I wanted. Or will this disrupt the cell's function is some way I'm not aware of? Will a continuous addition of 60/40 salt eventually lead to some unwanted saturation because I keep adding sodium ions and removing potassium?

Once I had added the 60/40 salt and noted a cloudy precipitation, I put the solution in the fridge and let it settle. It smelled quite strongly of hypochlorite. Is this a bad sign? After decanting, I removed the solids from the bottom and dried them. To put it to the test, I ground it to fine powder and mixed it with finely ground sugar and set it on fire.

There was clearly some oxidating action going on, but nowhere near what I would expect. A mix consisting of about 70% "chlorate" and 30% sugar by volume left most of the sugar uncombusted in the form of char. The decomposition just barely managed to sustain itself in a hot fizzle. Let's say it was about 10% of the power output I'd get from a KNO3/sugar mix.

Question #3: Why the poor performance? What did I do wrong? Clearly there's some chlorate in there, and it's also clear that it is not very concentrated. How could I determine what the impurity is? I suppose the main suspects are NaCl or KCl, and I'm thinking it might be good to know which it is.

mysteriusbhoice - 30-7-2020 at 02:02

Answer 1:
60:40 mixed salt works fine and infact better than pure KCl and also better for your electrodes but is only recommended when using MMO or using graphite + CaCl2 pH control.

Answer2:
Yes you can simply just keep adding sodium chloride to push out all potassium salts from the cell liquor and eventually you will be making sodium chlorate.

The cloudy precipitate is due to additives in your salt and that storebought 60/40 salt has talc in it which causes all the clouding so filter your salts through a microfiltration mesh which can be conviniently purchased as "scotch brite microfiber pad" it doesnt look like cloth but this weird leathery absorbant wiping cloth.

Answer3:
Your poor performance can be caused by a bunch of factors with stainless steel as cathode you need to have chromates in solution to prevent that side reaction and also addition of CaCl2 5% of electrolyte by wt will allow for poor man's pH control keeping pH at 6.8 throughout the run however only starts working when hypochlorites reach a certain concentration before pH suddenly drops to 6.8 from 8.6 and precipitation Ca(OH)2 which also can prevent reduction of chlorate and is overall better to use CaCl2 than worry about toxic chromate additives.

recommendationgs:
Add CaCl2 into your cell and increase current from 2 amps to 3.5 amps.
Once cell liquor goes from yellowish(alkaline) to clear(neutral) after hours or days increase current to 5 amps for current density of 138ma/cm^2 and you can go higher up to 7 amps but that requires you to really watch the pH.
Chromates make visual identification of cell pH harder and only recommended if you have pH meter since pH paper ends up getting bleached!.

links to my chlorate cell videos:
passive pH control setup
https://www.youtube.com/watch?v=haJnkx2Gnqk

Old non pH controlled salting out cell using 60/40 KCl mix and adition of NaCl to push out KClO3.
https://www.youtube.com/watch?v=u-FwKO6tOoE

[Edited on 30-7-2020 by mysteriusbhoice]

B(a)P - 30-7-2020 at 02:25

First general question I have is did you add some form of dichromate? If not I would highly recommend doing this.
Second general question what was your power source?
Third general question did you monitor pH? If so what was it?
A general comment, potassium chloride is generally cheaply available as a water softener have you tried looking for such products? You could also source KOH and neutralise it with HCl.
Another general comment, recycle your decant water, it contains dissolved chlorate and hypochlorate, making your next run produce your product faster.

#1: I have have done similar to you with a product we have is AUS called diet salt 50:50 by weight NaCl:KCl. It works fine for the reasons that you describe and in the end I got decent yields and reasonably pure KClO3 after a recrystallisation.

#2: If all you have is 60:40 then just use that as the starting product. If you do this though, maybe do a couple of recrystallisations to make sure your product is pure. Hypochlorite smell is good it means you are heading in the right direction. Was your sugar/chlorate mix completely dry? If you have sodium in the mix it can become very hard to dry your product sufficiently.

#3: I suspect you have some NaCl and NaClO3 which has absorbed water preventing your product reacting as expected. Try a recrystallisation then thoroughly dry both the chlorate and sugar and try again. You don't want to run your cell down to low or no chloride, to protect your anode. For this reason you will always need a recrystallisation to remove chloride from your product.

Hope this helps. Best of luck.

markx - 30-7-2020 at 03:36

Quote: Originally posted by Junk_Enginerd  
Once I had added the 60/40 salt and noted a cloudy precipitation, I put the solution in the fridge and let it settle. It smelled quite strongly of hypochlorite. Is this a bad sign? After decanting, I removed the solids from the bottom and dried them. To put it to the test, I ground it to fine powder and mixed it with finely ground sugar and set it on fire.

There was clearly some oxidating action going on, but nowhere near what I would expect. A mix consisting of about 70% "chlorate" and 30% sugar by volume left most of the sugar uncombusted in the form of char. The decomposition just barely managed to sustain itself in a hot fizzle. Let's say it was about 10% of the power output I'd get from a KNO3/sugar mix.



I trust you may have copercipitated chlorides into your sediment...thus the low performance of the sugar mix. Chlorate sugar mix is best avoided, to be honest. It is a combination that is far from safe. There are better alternatives to sample your product: e.g. mix with carbon powder, a strip of paper soaked in the cell liqour and set on fire etc.
Try recristallising your product: heat the solution until all of the solid phase dissolves, add water as required to reach such condition. Then let cool slowly in ambient air. Potassium chlorate cristallises from the solution as opalescent thin platelets. It is a very characteristic and beautiful event, that once seen allows you to assess very quickly if the product is really potassium chlorate or something else.

About measuring the cell pH level: this is not a trivial task, as indicator papers are basically useless. And the same goes for pH meters....the electrodes die very quickly and display erratic numbers that are of no use and can mislead one badly. There exist special electrodes for measuring the pH of chloralkali cells, but their price is unreasonably high for amateur experimetation and also their lifetime is quite limited. So the actual pH control of such a type of cell is pretty much done blindly and by guesstimative assesment of the reaction rate.

Either way one can easily do more harm than good trying to keep the cell pH near neutral. Not to mention that it requires constant babysitting coupled with a dosing system that tends to find ways to fail once you turn your back on it. Overdosing of acidic additives can lead the cell into a runaway reaction that destroys formed chlorates within seconds and liberates a serious cloud of free chlorine gas. I've lived through such a disaster once and it is no joke. If that were to happen in a closed room then the results from a 5L cell running away under overacidification are more that deadly.
Using alakali earth chlorides as a pH buffer is a safer approach, but I happily run my setups without interference to the pH level. Coupled with grade 2 Ti cathodes the reduction losses become negligible and there is no need to resort to chromates. When using Ti cathodes I also boldly ignore the reccomendation to keep cathode active surface area less than that of the anode. In fact I do the opposite having double the cathode area compared to the positive counterpart with no ill effect, on the contrary, the cell resistance drops and one can run more current through it at lower potentials and with less heat being generated.

[Edited on 30-7-2020 by markx]

mysteriusbhoice - 30-7-2020 at 04:23

Quote: Originally posted by markx  
Quote: Originally posted by Junk_Enginerd  
Once I had added the 60/40 salt and noted a cloudy precipitation, I put the solution in the fridge and let it settle. It smelled quite strongly of hypochlorite. Is this a bad sign? After decanting, I removed the solids from the bottom and dried them. To put it to the test, I ground it to fine powder and mixed it with finely ground sugar and set it on fire.

There was clearly some oxidating action going on, but nowhere near what I would expect. A mix consisting of about 70% "chlorate" and 30% sugar by volume left most of the sugar uncombusted in the form of char. The decomposition just barely managed to sustain itself in a hot fizzle. Let's say it was about 10% of the power output I'd get from a KNO3/sugar mix.



I trust you may have copercipitated chlorides into your sediment...thus the low performance of the sugar mix. Chlorate sugar mix is best avoided, to be honest. It is a combination that is far from safe. There are better alternatives to sample your product: e.g. mix with carbon powder, a strip of paper soaked in the cell liqour and set on fire etc.
Try recristallising your product: heat the solution until all of the solid phase dissolves, add water as required to reach such condition. Then let cool slowly in ambient air. Potassium chlorate cristallises from the solution as opalescent thin platelets. It is a very characteristic and beautiful event, that once seen allows you to assess very quickly if the product is really potassium chlorate or something else.

About measuring the cell pH level: this is not a trivial task, as indicator papers are basically useless. And the same goes for pH meters....the electrodes die very quickly and display erratic numbers that are of no use and can mislead one badly. There exist special electrodes for measuring the pH of chloralkali cells, but their price is unreasonably high for amateur experimetation and also their lifetime is quite limited. So the actual pH control of such a type of cell is pretty much done blindly and by guesstimative assesment of the reaction rate.

Either way one can easily do more harm than good trying to keep the cell pH near neutral. Not to mention that it requires constant babysitting coupled with a dosing system that tends to find ways to fail once you turn your back on it. Overdosing of acidic additives can lead the cell into a runaway reaction that destroys formed chlorates within seconds and liberates a serious cloud of free chlorine gas. I've lived through such a disaster once and it is no joke. If that were to happen in a closed room then the results from a 5L cell running away under overacidification are more that deadly.
Using alakali earth chlorides as a pH buffer is a safer approach, but I happily run my setups without interference to the pH level. Coupled with grade 2 Ti cathodes the reduction losses become negligible and there is no need to resort to chromates. When using Ti cathodes I also boldly ignore the reccomendation to keep cathode active surface area less than that of the anode. In fact I do the opposite having double the cathode area compared to the positive counterpart with no ill effect, on the contrary, the cell resistance drops and one can run more current through it at lower potentials and with less heat being generated.

[Edited on 30-7-2020 by markx]


CaCl2 is what I use for passive pH control and when you do not add chromates to your cell it can be seen once it starts working where your cell liquor goes from yellow to clear and Cl2 is continuously evolved throughout the run and hence my NaOH scrubber always ends up becomming yellow after each run.

Junk_Enginerd - 30-7-2020 at 04:35

Quote: Originally posted by mysteriusbhoice  
words


Great, thanks for confirming that.

Running it through 2x coffee filters 2 times gave a perfectly clear liquid. Good enough?

Right, the chromates. Almost forgot about them. Does it need to be specifically dichromate/hexavalent chrome? I had a go at synthesizing it but didn't succeed. Made it by stainless steel + HCl route. Something went wrong trying make it hexavalent with the chlorine. It either didn't oxidize or it was lost in the iron hydroxide sludge...

I've read a whole bunch about PH control and I'm pretty disappointed in the quality of the information I've found online... I'm an engineer and I like my info concise and clear, and I honestly haven't even seen exactly what PH it is one would aim for lol, or even what the precise reasons to so is... Okay, so CaCl2 could act as a PH limiter at least, but then wouldn't I have an annoying situation where I have solid potassium chlorate mixed with solid CaOH?

What's the reasoning behind the specific current levels you suggest? Is there any reason to use a higher current/current density other than proportionally higher production? Right now I've settled at 2.5 A mostly due to cell limitations. I don't want to stress the anode with excessive temperatures(50°C ish now at 2.5 A), plus I haven't yet built anything that handles the corrosive mist, and at 2.5 A it's operating pretty clean so far.

[Edited on 30-7-2020 by Junk_Enginerd]

B(a)P - 30-7-2020 at 04:47

pH - slightly acidic is best
dichromates are not essential, but improve yield dramatically - they prevent hypochlorite to chloride reactions at the cathode.
Current translates to reaction rate. If you have non-ideal reaction parameters (pH temp ect) then if the current is too low it may not push the rate of production past the rate of degradation form other factors

Junk_Enginerd - 30-7-2020 at 04:49

Quote: Originally posted by B(a)P  
First general question I have is did you add some form of dichromate? If not I would highly recommend doing this.
Second general question what was your power source?
Third general question did you monitor pH? If so what was it?
A general comment, potassium chloride is generally cheaply available as a water softener have you tried looking for such products? You could also source KOH and neutralise it with HCl.
Another general comment, recycle your decant water, it contains dissolved chlorate and hypochlorate, making your next run produce your product faster.

#1: I have have done similar to you with a product we have is AUS called diet salt 50:50 by weight NaCl:KCl. It works fine for the reasons that you describe and in the end I got decent yields and reasonably pure KClO3 after a recrystallisation.

#2: If all you have is 60:40 then just use that as the starting product. If you do this though, maybe do a couple of recrystallisations to make sure your product is pure. Hypochlorite smell is good it means you are heading in the right direction. Was your sugar/chlorate mix completely dry? If you have sodium in the mix it can become very hard to dry your product sufficiently.

#3: I suspect you have some NaCl and NaClO3 which has absorbed water preventing your product reacting as expected. Try a recrystallisation then thoroughly dry both the chlorate and sugar and try again. You don't want to run your cell down to low or no chloride, to protect your anode. For this reason you will always need a recrystallisation to remove chloride from your product.

Hope this helps. Best of luck.


I did not add any chromate. I was going to, but the synthesis of the dichromate failed and then I forgot about it lol. Apparently CaCl2 works as well, so I might go that way instead.

My power source at the moment is an advanced battery charger set to constant current. It's just temporary. I'll make a proper setup once I know the ins and outs of the process. Don't know what I'll use but I have plenty to choose from or build from scratch.

No ph monitoring. Don't have the most basic equipment to do it, and it seems like a mostly optional hassle as far as I have read.

No, I'll have a look at what the water softeners here are, thanks. KOH is unfortunately not much easier to find(I have stumbled upon it a few times as odd brands of drain cleaner, but the majority is NaOH), plus it'd be a little silly cost wise compared to salt.

I think it was quite dry, yes. Dried it in the oven at 150°C. The sugar wasn't dried, but since it works well with nitrate straight from the cupboard, it should work at least passably with chlorate regardless.

What's the general process of recrystallizing in this context? Heat/cool or evaporation?

mysteriusbhoice - 30-7-2020 at 09:32

the funny part about using 60:40 NaCl to KCl by wt salt is that even with the same amount of CaCl2 it takes longer for pH to drop to neutral which means for some reason it takes longer than using pure NaCl electrolyte which is weird maybe due to heavier potassium chloride vs NaCl then again I dont fully understand the mechanism of CaCl2 pH control.
It for some reason behaves normally drifting to alkaline till a certain point after a few hours and from yellow(alkaline) it turns clear(neutral) and Cl is evolved suddenly and I gotta hook up my NaOH scrubber to it.
Test for Cl2 confirmation is when my pH paper thats wett turns red and then bleaches when in contact with exhaust vapors of the cell.
I wonder if som1 out there has a better idea of why there is a delay on pH regulation using CaCl2 when starting up the cell for the first few hours.

B(a)P - 30-7-2020 at 12:31

Quote: Originally posted by Junk_Enginerd  


What's the general process of recrystallizing in this context? Heat/cool or evaporation?


Take advantage of the solubility at elevated temperature. In water at 100C 53 g/100 mL will dissolve and at 0C only 3 g/100 mL. Add just enough DH2O that your product will dissolve at 100C then heat to that temperature. Filter then allow to cool. You should see little plate crystals coming out of solution. Chill the solution down to ~0C and leave it for 24 h. Filter again, wash the crystals with a little chilled DH2O and you should have some pretty pure product. Retain the liquid and use that again in your cell as it will still have a little chlorate and likely chloride. The crystals should be nice and clear, no colour and plate like in form.

Junk_Enginerd - 1-8-2020 at 05:29
Quote: Originally posted by B(a)P  
Quote: Originally posted by Junk_Enginerd  


What's the general process of recrystallizing in this context? Heat/cool or evaporation?


Take advantage of the solubility at elevated temperature. In water at 100C 53 g/100 mL will dissolve and at 0C only 3 g/100 mL. Add just enough DH2O that your product will dissolve at 100C then heat to that temperature. Filter then allow to cool. You should see little plate crystals coming out of solution. Chill the solution down to ~0C and leave it for 24 h. Filter again, wash the crystals with a little chilled DH2O and you should have some pretty pure product. Retain the liquid and use that again in your cell as it will still have a little chlorate and likely chloride. The crystals should be nice and clear, no colour and plate like in form.


Hm. Well, I had another go at it. This time I managed to synthesize some sodium dichromate which I added into the cell. This was added about 50 Ah into this round. At the time of extraction I had about 80 Ah logged for ~500 ml of saturated solution of mixed NaCl and KCl, after checking again it's actually 35% KCl, 60% NaCl and the rest unspecified. I filtered off some cloudiness before using it.

I heated it to a boil in a stainless steel pan. This apparently wasn't the best idea as some reaction took place. I assumed most constituents won't react with stainless steel, but I've read now that at least dichromate does. Anyway, the contact with the stainless steel was a few minutes at most, so I'm hoping it doesn't have too bad adverse effects.
From what I could tell, some iron oxide or -hydroxide precipitated in small nodules on the pan, and I slowly saw a small amount of iron hydroxide "floof" precipitate in the liquid, and also noted a color shift in the liquid from pale yellow chromate color towards looking a bit more red/brown.

I then filtered it and left it in a glass jar to cool off. Then the weirdest thing started happening. It started fizzing. As crystals started forming, gas was also evolved. It looked very much like a had a big jar of champagne, the same kind of bubble trails that you get in carbonated beverages. Really pretty to be honest, except the gas was chlorine from what I could tell. It wasn't a lot of gas though, certainly not enough that I felt any need to set it outdoors. The smell wasn't only chlorine, there was another component to it that I couldn't quite identify. The best description I can come up with is chlorine combined with a hint of... metallic fart? Not a sulfurous smell, just... farty.

It's been sitting the fridge overnight now and I've certainly gotten a lot of crystallization. I was gonna start describing the crystals but at least here I can use a photo to convey my senses lol. It looks mostly like other pictures of potassium chlorate to me at least. Some more iron hydroxide has precipitated as well from what I can see. The liquid still has a heavy sickly chlorine smell.

I would appreciate some insights from others at this point. Why the the chlorine fizzle take place during cooling? Is that normal? What did I miss regarding the solutions reaction with stainless steel? Is it just the dichromate, or are other components reactive as well? Sure, I'll use glass the next time, but I would prefer to understand the reaction nonetheless.

[Edited on 1-8-2020 by Junk_Enginerd]

20200801_122836.jpg - 2.1MB

[Edited on 1-8-2020 by Junk_Enginerd]

mysteriusbhoice - 1-8-2020 at 08:07

Quote: Originally posted by Junk_Enginerd  


Quote: Originally posted by B(a)P  
Quote: Originally posted by Junk_Enginerd  


What's the general process of recrystallizing in this context? Heat/cool or evaporation?


Take advantage of the solubility at elevated temperature. In water at 100C 53 g/100 mL will dissolve and at 0C only 3 g/100 mL. Add just enough DH2O that your product will dissolve at 100C then heat to that temperature. Filter then allow to cool. You should see little plate crystals coming out of solution. Chill the solution down to ~0C and leave it for 24 h. Filter again, wash the crystals with a little chilled DH2O and you should have some pretty pure product. Retain the liquid and use that again in your cell as it will still have a little chlorate and likely chloride. The crystals should be nice and clear, no colour and plate like in form.


Hm. Well, I had another go at it. This time I managed to synthesize some sodium dichromate which I added into the cell. This was added about 50 Ah into this round. At the time of extraction I had about 80 Ah logged for ~500 ml of saturated solution of mixed NaCl and KCl, after checking again it's actually 35% KCl, 60% NaCl and the rest unspecified. I filtered off some cloudiness before using it.

I heated it to a boil in a stainless steel pan. This apparently wasn't the best idea as some reaction took place. I assumed most constituents won't react with stainless steel, but I've read now that at least dichromate does. Anyway, the contact with the stainless steel was a few minutes at most, so I'm hoping it doesn't have too bad adverse effects.
From what I could tell, some iron oxide or -hydroxide precipitated in small nodules on the pan, and I slowly saw a small amount of iron hydroxide "floof" precipitate in the liquid, and also noted a color shift in the liquid from pale yellow chromate color towards looking a bit more red/brown.

I then filtered it and left it in a glass jar to cool off. Then the weirdest thing started happening. It started fizzing. As crystals started forming, gas was also evolved. It looked very much like a had a big jar of champagne, the same kind of bubble trails that you get in carbonated beverages. Really pretty to be honest, except the gas was chlorine from what I could tell. It wasn't a lot of gas though, certainly not enough that I felt any need to set it outdoors. The smell wasn't only chlorine, there was another component to it that I couldn't quite identify. The best description I can come up with is chlorine combined with a hint of... metallic fart? Not a sulfurous smell, just... farty.

It's been sitting the fridge overnight now and I've certainly gotten a lot of crystallization. I was gonna start describing the crystals but at least here I can use a photo to convey my senses lol. It looks mostly like other pictures of potassium chlorate to me at least. Some more iron hydroxide has precipitated as well from what I can see. The liquid still has a heavy sickly chlorine smell.

I would appreciate some insights from others at this point. Why the the chlorine fizzle take place during cooling? Is that normal? What did I miss regarding the solutions reaction with stainless steel? Is it just the dichromate, or are other components reactive as well? Sure, I'll use glass the next time, but I would prefer to understand the reaction nonetheless.

[Edited on 1-8-2020 by Junk_Enginerd]



[Edited on 1-8-2020 by Junk_Enginerd]


use ceramic coated or teflon coated pots only!!
you can also use aluminum pan if your cell is pH controlled as the neutral solution wont eat the aluminum.

markx - 1-8-2020 at 12:12

Stainless steel is incompatible with halogen bearing solutions, like the one originating from a chlorate cell. That goes pretty much to most metals and alloys....except perhaps pure Ti and some noble metals of the PMG . Use glass or PE PP plastic vessels to handle and store the solutions.

As for what caused the chlorine evolution in your "primordial stew" shall probably elude a clear explanation. The causes can be manifold considering that you had a chromate doped cell liqour reacting with a stainless alloy. Perhaps the metallic constitiuents of the mix promoted the breakdown of residual hypochlorite and even some of the chlorate contained in the solution. Many redox processes arise in such a complex mix. I would suggest to keep things as simple as possible to eliminate the numerous possibilities to failure/detrimental sideractions that always arise if one decides to include a lot of variables simultaneously.

By the way your cristals look suspiciously like KClO3, so probably you succeeded in extracting some of the wanted product :)

RogueRose - 1-8-2020 at 15:44

I'm wondering if we could order a 12" x 36" (or more) MMO for the site and split it between members. I've seen some suppliers that offer BIG discounts on larger orders like this, coming out at like 20-40% the cost. I know I would like a decent sized one, maybe 2 that are 30-48" sq each.

Or if anyone here can make them, it might be worth asking if there is interest. If I had access to rutherium and iridium and palladium at reasonable prices, I'd do it. I may be able to get Pt and Pd actually from a local jeweler if that would help out.

mysteriusbhoice - 2-8-2020 at 04:30

Quote: Originally posted by RogueRose  
I'm wondering if we could order a 12" x 36" (or more) MMO for the site and split it between members. I've seen some suppliers that offer BIG discounts on larger orders like this, coming out at like 20-40% the cost. I know I would like a decent sized one, maybe 2 that are 30-48" sq each.

Or if anyone here can make them, it might be worth asking if there is interest. If I had access to rutherium and iridium and palladium at reasonable prices, I'd do it. I may be able to get Pt and Pd actually from a local jeweler if that would help out.

MMO electrodes can last for 20 years of continuous use at 200ma/cm^2 if you have pH control via CaCl2 or HCl drip system.
running at lower current density like 100ma/cm^2 due to temperature constraints in my cell particularly it can last 40 years of continuous usage though I notice my cathode is erroding as titanium encounters hydrogen embrittlement much sooner.
my electrodes are 2 years old and it appears my cathode is suffering way before the anodes do.
there is this 1 shop that seems to sell eletrodes
https://electrodesupply.com/electrodes/
they appear to be the same ones I got way back when.

Junk_Enginerd - 5-8-2020 at 00:16

Quote: Originally posted by markx  
Stainless steel is incompatible with halogen bearing solutions, like the one originating from a chlorate cell. That goes pretty much to most metals and alloys....except perhaps pure Ti and some noble metals of the PMG . Use glass or PE PP plastic vessels to handle and store the solutions.

As for what caused the chlorine evolution in your "primordial stew" shall probably elude a clear explanation. The causes can be manifold considering that you had a chromate doped cell liqour reacting with a stainless alloy. Perhaps the metallic constitiuents of the mix promoted the breakdown of residual hypochlorite and even some of the chlorate contained in the solution. Many redox processes arise in such a complex mix. I would suggest to keep things as simple as possible to eliminate the numerous possibilities to failure/detrimental sideractions that always arise if one decides to include a lot of variables simultaneously.

By the way your cristals look suspiciously like KClO3, so probably you succeeded in extracting some of the wanted product :)


After a second extraction, I can at least confirm that the boiling in the stainless steel pot was probably connected to the chlorine "carbonation" fizzle. Nothing like that happened when I this time boiled it in a glass pot.

And oh yeah it was chlorate. Stirred up a teaspoon of the extracted and ground powder with charcoal powder and lit it up, and daaamn. I'm all giddy now. That little pile produced an instant 50 cm little mushroom cloud. Time to get that other project going and have my ball mill start churning metal powders...

Quote: Originally posted by RogueRose  
I'm wondering if we could order a 12" x 36" (or more) MMO for the site and split it between members. I've seen some suppliers that offer BIG discounts on larger orders like this, coming out at like 20-40% the cost. I know I would like a decent sized one, maybe 2 that are 30-48" sq each.


What do you need such a big one for? I was wondering if I should have bought a bigger one, but at a lowly 2-3 Amps my cell seems to spit out like 30-50 grams per week now, and I haven't even tried to refine and effectivize any of the steps yet. I don't think I'll ever catch up to the production tbh. Is it just for big booms, or are there other projects that consume large amounts of chlorate?

markx - 5-8-2020 at 08:09
Quote:

And oh yeah it was chlorate. Stirred up a teaspoon of the extracted and ground powder with charcoal powder and lit it up, and daaamn. I'm all giddy now. That little pile produced an instant 50 cm little mushroom cloud. Time to get that other project going and have my ball mill start churning metal powders...


Congrats! Just be careful about mixing the stuff.....it is awe inspiring how much of a punch chlorate formulations pack. A good teaspoonful of flash type going off on top of a rocket at the right altitude is enough to trigger car alarms and dogs over an entire village :D

But yes, the experimentation with even moderately sized electrosynthesis setups shall usually stock one up with product way faster than can be reasonably consumed. Unless you just dump it into a bonfire by the jarful...

[Edited on 5-8-2020 by markx]