Muzz1969
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Electrolysy Electrodes
Has anyone tried using Thoriated Tungstan rods as cathodes and anodes, in place of the usual carbon rods or platinum. Thorium and Tungstan are
resistant to most chemicals and extremely good conductors. They are available from welding suppliers at $25 for a pack of 10 x 200mm long. Any
thoughts ?
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m1tanker78
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Tungsten will form an insulating oxide skin and stop conducting current (at least at the anode).
Chemical CURIOSITY KILLED THE CATalyst.
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hissingnoise
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And dissolve in a chlorate cell to form the hexachloride . . .
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Muzz1969
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Yes tungstan on its own may, but only under certain very limited conditions as described here http://www.tungsten.com/tungcorr.html, but it seems to me that only happens in a very arrow field of operation making the rods still viable for
most reactions, also that these rods are not pure tungstan they are a mix of thorium and tungstan the whole point of the design is to stop oxidation
so that the current will continue to flow whilst welding. I have purchased a back and will let you know how they go during a Bromate work up .
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m1tanker78
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Quote: Originally posted by Muzz1969  | | ... the whole point of the design is to stop oxidation so that the current will continue to flow whilst welding. I have purchased a back and will let
you know how they go during a Bromate work up . |
Keep in mind that argon in the GTAW process not only protects the weld but also protects the electrode from oxidation. I imagine it would dissolve in
a chlorate cell as hissingnoise pointed out. I don't remember what I attempted this with but it just stopped conducting and I gave up on it.
Chemical CURIOSITY KILLED THE CATalyst.
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hissingnoise
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| Quote: | | . . . these rods are not pure tungstan they are a mix of thorium and tungstan the whole point of the design is to stop oxidation.
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Thorium is much too reactive to be of use in electrolysis ─ reactivity such that when finely divided the metal is pyrophoric . . .
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WGTR
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Added thoria lowers the work function of tungsten electrodes. This gives the electrodes better low current performance, and allows them to operate at
lower overall temperatures. This in turn improves service life. As far as I know, it doesn't do anything to improve corrosion resistance. The
electrodes are always protected from atmosphere with an inert shield gas during welding. Otherwise, the tungsten erodes away almost instantly.
Thorium is an alpha emitter, but is quite safe when in alloy form with the tungsten. If you use the electrodes in a manner other than the way they
were intended, it pays to ensure that one isn't inadvertently poisoning oneself. The dust is an inhalation hazard, and any soluble salts may be a
problem if ingested.
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m1tanker78
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Makes me wonder ... with all the lanthanated/thoriated tungstens i've ground in my lifetime. 
Chemical CURIOSITY KILLED THE CATalyst.
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Muzz1969
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Thanks for all the input guys , some interesting information to chew on.
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