4-Stroke
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Making Extremely Cheap Carbon Electrodes for Chlorate Production (Without Graphitization)
Hello everyone!
The production graphite electrodes, primarily for use in chlorate cells, has been an ongoing project for quite a while now. Of course, they can be
purchased, but even graphite electrodes are relatively expensive, especially if they are needed in large amounts, and even more so now that the export
of (high quality - you can still buy gouging rods and the like) graphite electrodes has been banned by China. So, the only option that remains
cost-effective for large scale production of chlorates is making your own electrodes.
The Current Method of Producing Carbon Electrodes
So far, the current DIY process of producing graphite electrodes pretty much boils down to taking a conducting carbon powder (graphite/charcoal/etc.),
combining it with a soluble binder (such as sugar) that carbonizes at high temperature, combining the dissolved binder with the conductive carbon,
pressing it together, carbonizing the binder by heating the electrode to very high temperature, repeatedly soaking and carbonizing the electrode, and
finally impregnating it with a suitable resin. There are a number of problems with this approach, such as:
-Very high temperature (that also has to be in a non-oxidizing environment as otherwise the electrode will burn) is required to carbonize the binder.
-The electrode has to be repeatedly saturated with a binder solution and carbonized to achieve an acceptable conductivity, density, and strength.
-Many binders, such as sugar, leave weak foam-like carbon, which also decreases strength, conductivity, and mechanical strength.
-The process is only really suitable for cylindrical electrodes, which are much less preferable than thinner rectangular electrodes (in my opinion).
-The produced electrodes are of a lower quality and degrade relatively fast, even if impregnated with a resin.
-The process is generally much more labor intensive
The Proposed Method of Producing Carbon Electrodes
Now, the much simpler method that I think could potentially work for producing carbon electrodes basically consists of combining a conductive carbon
powder with a non-soluble (e.g. plastic) binder that is left there and not carbonized. The binder
itself could be pretty much anything, as long as the electrode itself stays conductive and the binder used would not rapidly degrade in the
environment it's being used in (e.g. an aqueous solution NaCl and NaClO3). The fact that such electrodes could be made has been proven many
times, but whether they would survive in a chlorate cell remains unclear, although I don't see any reason why they wouldn't. Here are some example of
such electrodes being made:
https://www.youtube.com/watch?v=CJnWq3MzMNo (Graphite + carbon black + PVA glue --> flexible carbon electrodes)
https://www.youtube.com/watch?v=ht0eZsSHUDA (Graphite + EPS foam in acetone --> rigid waterproof graphite electrodes with lower resistance)
https://www.youtube.com/watch?v=sgnGdj6CFe8 (Graphite + epoxy --> strong, stiff, and even more conductive electrode)
I could post more example (which can be found), but I think you all get the point. Conductive carbon powder + polymer binder --> carbon electrode.
Now, all of the example above (and all other ones I could find) were intended to be used in batteries, where they performed well. But it is still
unknown whether the electrodes would perform as well in a chlorate cell. If it does end up working, this method would be superior to the conventional
way in pretty much every aspect, as it:
-Does not require high temperature or any equipment at all
-Can be mass-produced very easily and cheaply while being much less labor intensive
-Can be used to make rectangular, thin plates, and also results in electrodes with much better mechanical strength
-Proven to produce reliable electrodes with (sufficiently) low resistance
-Pretty much any binder can be used, such most plastics soluble in any solvent, thermoset epoxies, most waterproof glues, varnishes/lacquers/other
solvent-based coatings, other resins, maybe even molten plastics.
The only problem I can foresee is the possibility that once the carbon particles ablate, unlike normal graphite electrodes that simply "shed" their
entire surface slowly and are completely made of conductive graphite, in those electrodes the polymer structure could remain and eventually result in
an unacceptably high resistance of the cell. This could easily be fixed simply by scraping it with sandpaper, but if this were to happen too fast,
that would make the electrodes unusable.
I don't know if such a thing would even occur (maybe, for example, the bubbles formed during electrolysis would also ablate the fragile remaining
polymer structure mechanically and thus prevent it from forming a thick "mesh" on top of the electrode's conductive surface), but if it does, I think
that it could be mitigated simply by using a significantly lower current density (<10mA/cm2) to slow down the degradation process
considering how easy and cheap the electrodes are to produce.
Any thought?
Thank you
P.S. I know that magnetite anodes are suitable for both chlorate and perchlorate production, and also that steel forms
a layer of it during electrolysis in NaOH. So could a steel anode that was electrolyzed at very high current density for some time and formed a
relatively thick magnetite coating be used as an anode for chlorate or even perchlorate production?
Ukrainium
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Hexabromobenzene
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Have you seen my thread? Charcoal from laminate flooring scraps, acid-hydrolyzed flour, or a mixture of sugar and bone glue with a little acid. Then
impregnate with paraffin or a polypropylene paraffin solution. It couldn't be cheaper.
Carbon electrodes have good durability. Even with poor impregnation and a simple sugar binder without the addition of amines for cross-linking, 20mm
diameter electrodes last for 2-3 days in a sulfuric acid solution. A graphite welding electrode deteriorates within a few hours.
The technology is simple. You'll need a simple forced-air furnace to heat the charcoal to just 1,000 degrees Celsius. That's not much. You will burn
some of the coal but get conductive coal. To insulate the electrode from the air, use an iron sheet from an aerosol can.
https://www.sciencemadness.org/whisper/viewthread.php?tid=15...
Also, if you want to produce perchlorate, you can try lead electrodes. You'll need chlorate that's as pure as possible, free of chloride, and some
sulfate added to the solution. This might work.
[Edited on 8-11-2025 by Hexabromobenzene]
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Hexabromobenzene
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Posts: 262
Registered: 27-4-2021
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Electrodes shown in the video will be quickly destroyed by electrolysis. You need thick electrodes for durability. You can use electrodes from
electric train pantographs. These are typically made of graphite powder with phenol-formaldehyde resin, but they may be even less durable than baked
electrodes. Baked electrodes do not disintegrate into powder but delaminate. And you can slow down this process very much with a good impregnation.
[Edited on 8-11-2025 by Hexabromobenzene]
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