Chemgineer
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Perchlorate cell cathode
I have been running a sodium perchlorate cell with a PbO2 anode and a Ti mesh cathode, One thing that keeps happening is the cathode gradually bends
and curves away from the anode.
This doesn't happen with my chlorate cell with MMO and Ti.
Has anyone else had this happen?
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Rainwater
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When I was testing reaction conditions, using 22awg titanium wire coated in PbO and high current I noticed this, figured it was a thermal expansion
effect, like with a bi metal strip
"You can't do that" - challenge accepted
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yobbo II
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I think its hydrogen absorption on one side more that the other.
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Chemgineer
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That could be right because eventually the cathode fails and it might be because of hydrogen embrittlement.
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mysteriusbhoice
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Quote: Originally posted by Chemgineer | I have been running a sodium perchlorate cell with a PbO2 anode and a Ti mesh cathode, One thing that keeps happening is the cathode gradually bends
and curves away from the anode.
This doesn't happen with my chlorate cell with MMO and Ti.
Has anyone else had this happen? |
I actually want to know how to get a Ti mesh to become like this because they make for a very good substrate.
Anyways this is why i've stopped using Ti cathodes apart from it's terrible H2 evolution potential causing it to reduce the electrolyte lowering
efficiency.
Use a copper or nickel cathode for perchlorate cells as it's much better. Lead cathode is even worse than Ti has highest H2EP. Steel is decent if
nickel plated or carbon steel.
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