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Topic: Oxide build up on electrodes  (Read 4086 times)

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Offline gre

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Oxide build up on electrodes
« on: June 23, 2009, 12:39:04 PM »
Hello,

While performing (8V) electrolysis on a cell constructed of concentric 316L stainless steel tube electrodes, I noticed a thick white layer had  formed on anode (outside electrode)  in the cell gap..  And on the inside of the cathode tube (inner electrode tube) there was a dark gray layer...   What are these layers exactly?

Thanks in advance.


Offline Borek

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Re: Oxide build up on electrodes
« Reply #1 on: June 23, 2009, 12:51:14 PM »
Knowing electrolyte won't hurt...

But I doubt we will be able to help. Way too many possibilities.
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Offline gre

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Re: Oxide build up on electrodes
« Reply #2 on: June 23, 2009, 05:48:36 PM »
What are the variables?   Could it just be a 'cocktail' of oxides from the 316L composition?  I  was just using distilled water.



Offline gre

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Re: Oxide build up on electrodes
« Reply #3 on: June 24, 2009, 02:12:19 PM »
Anyone?

Offline gre

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Re: Oxide build up on electrodes
« Reply #4 on: June 25, 2009, 12:06:58 PM »
It seemed strange that a 'gray layer' would form on the inside of the cathode tube where current doesn't pass..   Is this normal?


Offline gre

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Re: Oxide build up on electrodes
« Reply #5 on: June 28, 2009, 12:47:15 AM »
Could the gray layer be hexavalent chromium?
 

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