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Using lightning for electrolysis

  1. Jan 14, 2007 #1
    I was wondering what would happen if you somehow were able to harness a bolt of lightning into an electrolysis reaction? Normally you would use DC current and put 2 electrodes in a bucket of water. The water will split into 2 hydrogen and 1 oxygen molecule. With the lightning, you would have the lightning source current for one electrode and somehow attach the other electrode into the ground to make a large potential difference.

    My question is: If you wanted to create a massive volume of H2 gas, could you put a lightning rod into the air and have the strike ionize the water and capture this into a tank that would store it? Assume that if you made too much H2 that there would be a bypass to stop the tank from exploding from the pressure
  2. jcsd
  3. Aug 27, 2015 #2
    Lightning does react with elements, but not by electrolysis, one good example is that the extreme heat of a lightning breaks N₂, and O₂ bonds in the air, then these atoms rearrange resulting in O₃ and NO₂, nitrogen dioxide reacts with water and becoms nitric acid. Maybe a lightning striking the ocean may result in electrolysis since salt water does have a good amount of ions.
  4. Aug 27, 2015 #3
    I think that the voltage would be so high you'd get a mess of side reactions that wouldn't be possible at regular voltages. Also due to the high voltage, the current would be high enough to heat the water to very high temperatures. Wikipedia says this: At elevated temperatures water molecules split into their atomic components hydrogen and oxygen. For example at 2200 °C about three percent of all H2O molecules are dissociated into various combinations of hydrogen and oxygen atoms, mostly H, H2, O, O2, and OH. Other reaction products like H2O2 or HO2 remain minor. At the very high temperature of 3000 °C more than half of the water molecules are decomposed, but at ambient temperatures only one molecule in 100 trillion dissociates by the effect of heat.

    Using distillation methods... and some kind of bypass, it would definitely be possible to extract H2 in this way.

    Also, using multiple electrolytic cells in series would decrease the voltage at each one.
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