CrimpJiggler
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Chlorate cell - Why mixed electrodes?
I was just reading about the electrochemical synthesis of chlorates using cells with a mixed metal oxide anode and a stainless steel cathode.
Electrochemistry fascinates me but my experience with it is limited to generating Cl2 via the electrolysis of NaCl solution using a pair of graphite
electrodes. What advantage would using 2 different types of electrodes have? In a chlorate cell, does the anode wear down faster or something?
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Diablo
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In a chlorate cell (and electrolysis in general) the anode wears down or is dissolved unless it is inert. Carbon works and is cheap, but it erodes
quickly. Platinum works very well, but it is very expensive, so MMO anodes are used. They are an affordable alternative to platinum and should work
nearly as well.
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cyanureeves
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yep. i got the mixed metal oxide anode and it has been working non stop for months. i use a titanium cathode because it also lasts forever it seems. i
read that in cold temps my cell makes alot of hypochloride so i just let it work through until it warms during the day. i get tired of switching on
and off.
[Edited on 7-2-2012 by cyanureeves]
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Vikascoder
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Generally multi metal oxides are used because one of them is strong oxidizing agent which oxidizes the metal on which it is coated so to prevent this
different oxiders are used one of the oxide doesnt oxidise the metal so first it is coated on metal then other metal oxide on the previous layer of
oxide
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