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Can ionizing radiation split water?

  1. Dec 12, 2013 #1
    I was just wondering if ionizing radiation can split water into hydrogen and oxygen? Thanks in advance :)
     
  2. jcsd
  3. Dec 12, 2013 #2
  4. Dec 12, 2013 #3
    Cool thank you for the link:) do you know if it is more or less efficient then using the electric method?
     
  5. Dec 13, 2013 #4

    Astronuc

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    Radiolysis produces a variety of radicals, and the radicals will react with other species (e.g., cations) in the water. Once a water molecule splits into H + OH, it will try to recombine. One would need some way to collect H and O from the water in order to mitigate the recombination.

    For operating nuclear reactors, radiolysis in important with respect to the electochemical potential of the water - as are the soluble gases and impurities. Corrosion and corrosion products get activated in a neutron field.
     
  6. Dec 13, 2013 #5
    Ok so lets say one where to use a standard electrolysis and expose it to a high energy radiation source, would that help separate the ions? And would it help reduce the electrical energy needed? I have also thought about using ultrasound to help supply the energy needed but i dont know if it will work.
     
  7. Dec 13, 2013 #6

    SteamKing

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    Well, for one thing, you don't need a license to split water with electricity. If you start handling radioactive sources, all sorts of official regulatory and security bodies get concerned.
     
  8. Dec 13, 2013 #7
    Thats true, so can i use some kind of high energy EM radiation? Say Xrays, if i recall correctly old crt screens can be modified to emit Xrays and be set up to focus them at a single point.
     
  9. Dec 13, 2013 #8

    SteamKing

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    Any type of high-energy radiation like X-rays is dangerous. That's why X-ray labs and the personnel who work in them are shielded from exposure to X-rays. Again, using these techniques cause concern from regulatory and security agencies. It's not something to be fooling around with casually.
     
  10. Dec 13, 2013 #9
    Yes steamking i know that, and i wont be playing with radiation anytime soon. I have no interest in getting anyone hurt or myself. But my question still stands, Would Xrays used in conjunction with electricity work to split water more effectively then conventional methods?
     
  11. Dec 13, 2013 #10

    SteamKing

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    I doubt it, otherwise you would see all kinds of 'X-ray oxygen' all over town. It takes more than juking with second hand CRTs to create reliable, high-energy X-ray sources, plus the cost of the electricity to run them, which could be used directly to hydrolyze water instead of being fed into an X-ray machine first.
     
  12. Dec 13, 2013 #11

    Drakkith

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    If you're interested, here is a paper on the efficiency of electrolysis of water to produce hydrogen and several methods to increase the efficiency.

    http://www.electrochemsci.org/papers/vol7/7043314.pdf
     
  13. Dec 13, 2013 #12
    Thank you i will read it soon
     
  14. Dec 14, 2013 #13

    Astronuc

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    Radiolysis is absent in the cited paper, so there is an opportunity to review applications of radiolysis to electrolytic separation of hydrogen from H20. Radiolysis does provide energy (via ionization) to break the water molecule, and the ionziation of the water will improve the conductivity.

    One aspect of radioactive sources is that they cannot be turned off (decay is an ongoing process), and shielding must be used if humans (or other life forms) are in the vicinity of the radiation field.
     
  15. Dec 14, 2013 #14
    Forgive me if this seems to be a silly question I'm not a physicist, I'm a bio major. Will either of the products (H/O2) have a chance of being radioactive?
     
  16. Dec 14, 2013 #15

    Astronuc

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    The water would not be radioactive if the source emits beta (electrons) and gamma rays. They interact with the atomic electrons through ionization.

    Matter becomes radioactive when the nucleus is changed from a stable isotope/nuclide to an unstable isotope, usually by absorption of a neutron, or interaction with a high energy particle, e.g., proton, or other nuclear (subatomic) particle. The latter implies a spallation reaction, but they require high energy.

    In nuclear reactors which use the fission process, the neutron field is established through the fission process in which 2 or 3 neutrons are emitted from the fission, along with fission products. Otherwise, some initial neutrons are produced from (α, n) reactions, or (γ, n) reactions, or possibly through spontaenous fission reactions. Spontaneous fission is a decay mode of some transuranic nuclides.

    Ideally, radiolysis is acheived without a neutron field, but rather using gamma and beta particles.
     
  17. Dec 15, 2013 #16
    would it be possible to use a magnetic field to separate the H and O ions? I know that plasma can be guided with magnets? also what is the difference between beta particles and the electrons coming from an electron "gun" as found in a crt? (steamking I know you wanna fuss but relax i don't intend to actually build anything with a crt)
     
  18. Dec 16, 2013 #17
    If the water is moving and there is a magnetic field crossing the flow then the + and - ions will be pushed the opposite way withing the flow (MHD effect, google it). But: this is not a separation.

    There are just practical differences. Energy spectrum, randomness, amount, direction, focus, usage.
     
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