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Electrolysis using Displacement current?

  1. May 21, 2016 #1
    electrolysis.png
    The figure shows two insulated metal electrodes kept in pure water with a small gap between them.

    When sufficiently large voltage pulses applied between electrodes, there is a flow of displacement current through the insulators and water, but will this split the water molecules because of the E feild ?

    all your answers are welcomed !
     
  2. jcsd
  3. May 21, 2016 #2

    anorlunda

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    Normally, electrolysis occurs at the anode and cathode, not in the water in the middle. Your diagram shows an insulation layer that prevents contact of the water from the anode and cathode.

    What kind of electrolysis reaction are you expecting? The reduction reaction (see below) require electrons, but the number of free electrons in pure water due to displacement current will be exceedingly small. You should be able to calculate the energy needed for an oxidation reaction, and compare that with energy available from the displacement current in the immediate vicinity of an H2O molecule.

    It sounds difficult to make that work. But you did not specify the voltage level, and if we keep increasing the voltage pulse magnitude eventually something(?) should happen. Neither did you specify how much electrolysis is needed to declare success (a single molecule or more?).

    https://en.wikipedia.org/wiki/Electrolysis_of_water
     
  4. May 21, 2016 #3

    CWatters

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    Pretty sure the short answer is no...

    http://[URL [Broken][/url]

    More..


    Edit: Sorry about the formatting of this post. For some reason the editor is preventing me fix it.
     
    Last edited by a moderator: May 7, 2017
  5. May 21, 2016 #4
    well folks, this idea is nothing about chemical electrolysis that involve oxidation and reduction , its simply a "dielectric break down" of water due to strong electric feild.

    I called electrolysis because it produces similar effects of separating H2O molecule.
     
  6. May 21, 2016 #5

    anorlunda

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  7. May 21, 2016 #6
    Valuable Information @anorlunda...

    65 MV/meter is 65 KV / millimeter, we can use Flyback transformer.

    Plus heat and frequency will lower the Breakdown voltage.
     
  8. May 21, 2016 #7

    anorlunda

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    I'm not sure if there is a distinction between "pure water" and "distilled water" , if yes it might make a big difference. You should research it more for pure water.
     
  9. May 21, 2016 #8

    CWatters

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    Is the "strong electric field" across the water or across the insulators?
     
  10. May 21, 2016 #9
    across the water
     
  11. May 21, 2016 #10

    CWatters

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    For that to be true the water would need to have a higher impedance than the insulators.
     
  12. May 23, 2016 #11
    In general - dielectric breakdown yield a plasma, and a plasma underwater would at least be a steam explosion and considering you are separating into Hydrogen and Oxygen - and then you have a plasma (ignition source), really does not seem practical to do this. Part of the benefit of traditional electrolysis is the Oxygen and Hydrogen are generated at different locations. Distilled or De-ionized Water - ether may "work" if you measure the conductivity first.

    And then - As CW points out you still have the electrodes insulation - so as the water approaches a breakdown (effectively lowering the resistance of the water) then the the voltage applied will be across the electrodes' insulation.
     
  13. Jun 2, 2016 #12
    well ...i thought insulating the electrode will prevent the flow of Real Current (Amps), so that all we need for electrolysis will be Voltage... but as You say it sounds difficult to acheive.
     
  14. Jun 2, 2016 #13

    CWatters

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    You cannot electrolyse water with just voltage or just current. It takes power/energy.
     
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