dangerous amateur
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Chlorate Cell: Questions about Anodes
Hi,
I'm beginning to be interested in homemade chlorate.
If you have those MMO mesh sheets - do you protect the cutting area of the sheet? And if, how?
And if I cannot get hold of MMO sheets - I can get MMO alloy in chunks. Has somebody ever tried to coat something else with MMO?
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Bot0nist
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Check out the search function on this site. Anodes (especially MMO) and chlorate cells have many dedicated threads already here at SciMad, all chock
full of information.
U.T.F.S.E. and learn the joys of autodidacticism!
Don't judge each day only by the harvest you reap, but also by the seeds you sow.
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White Yeti
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I agree with Bot. You're new here, so I'll tell you that the search engine is your best friend. The search function is right below the SciMad logo.
There's this one page about PbO2 anodes that's so long, you'll need hours to read the whole thing:
https://www.sciencemadness.org/whisper/viewthread.php?tid=24...
Another page is on cobalt oxide anodes:
http://www.sciencemadness.org/talk/viewthread.php?tid=9572
Another thread is just on anodes in general:
http://www.sciencemadness.org/talk/viewthread.php?tid=5050
I've actually tried making chlorate, but I make it a little differently. I make bleach first (by electrolysing a brine solution with carbon
electrodes) and then I boil the bleach down until the bleach disproportionates into salt (that precipitates out) and sodium chlorate. I then
precipitate it out of solution with potassium chloride, filter and dry.
Have fun, and be careful
"Ja, Kalzium, das ist alles!" -Otto Loewi
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Bot0nist
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While the thermal disassociation of a sodium hypochlorite solution into sodium chloride and sodium chlorate is an easy way to get a little chlorate,
it is terribly inefficient. Only a small fraction of the NaClO goes to NaClO<sub>3</sub>. An electrochemical cell is by far the best route
to homemade potassium/sodium chlorate.
U.T.F.S.E. and learn the joys of autodidacticism!
Don't judge each day only by the harvest you reap, but also by the seeds you sow.
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White Yeti
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You're absolutely right, but an electrochemical cell is only good when you have a good anode. I don't have access to MMO and my MnO2 anodes have
failed horribly in the past and I didn't try to make them again ever since. I certainly don't want to experiment with PbO2 given that I can't even
make MnO2 anodes at this point.
I experiment with little amounts of chlorate at a time, so I don't need an industrial scale electrolytic cell that churns out hundreds of grams of
chlorate every day. I use chlorate as an oxidizer in a new kind of battery that I'm developing. It hasn't worked out too well so far, but I'm getting
closer and closer to a finished product.
"Ja, Kalzium, das ist alles!" -Otto Loewi
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sxl168
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I don't even bother making Lead anodes. I just use a bar/rod/plate of Lead as an anode. If the accumulation of flaked off PbO2 concerns you, just
decant off or filter your solution, collect the PbO2 and dump it inside a junk Lead Acid battery and send it off to the recycler. Lead is easy to
melt, mold, form, and cheap and suits my needs for this application. Keeping the current under 100 mA/cm^2 of surface Lead area helps keep shedding
down.
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dann2
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Great. Another easy Anode for Chlorate (and Perchlorate too!) production.
Can you tell us how many grams of Chlorate you have made with the Lead Anode. Is it Sodium or Potassium Chlorate?
How long does the Lead last, that is, how much if it corrodes away for every KG of Chlorate that you manage to make.
etc etc etc etc
Dann2
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sxl168
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I don't have any specific numbers as i've only dabbled a little bit with it. I was electrolyzing NaCl and Na2SO4 solutions. My experience is that a
few grams to tens of grams of PbO2 is shed per 100 AH. I wish I had more specific info to give, but I never bothered to record detailed info and it
was just small experiments here and there.
I have easy access to Lead, so I offered that as a solution since many others have easy access to it as well. It works well so long as you don't mind
the fact that it will shed off PbO2 and the anode will be consumed. PbO2 settles fast and easy to filter which makes it 100x better than carbon rods.
BTW, don't use battery plates for the anodes as they will crumble quickly. I use the battery posts and the interconnecting Lead straps inside of
batteries as the anodes, or better yet, a Lead brick if you can get ahold of those. Note also that the battery posts used on car batteries is usually
a 5% or so Antimony Lead alloy for hardness. Googling around turned up results saying that this alloy and Lead-Silver alloys are used in industry to
slow down shedding.
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cyanureeves
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howdy! i'm using one of those mmo mesh anodes right now and i dont cover or protect the mesh that exposes the titanium because as you may know
titanium passivates. true to the fact, it does form a coating and the mesh has been going for about a month now. i've made three different cells and
am still using the same anode.
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dann2
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O Dear,
I was being a bit sarcastic when I said that Lead was a great Anode.
Are you sure it works to make Chlorate?
How much Chlorate have you made (in grams) using a Lead Anode?
I would be inclined to think you will end up with a toxic mess of Lead Chlorate + some insoluble Lead compounds.
Will have to try it. It's one of those Anodes doing the rounds for years with some claiming quite good success and others (myself) stating it is
useless.
It appeared in one of the 'black books' way back in time.
It would be useless for Perchlorate IMO.
Dann2
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