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Proton question

  1. Jun 2, 2008 #1
    Iam a maths student so forgive my lack of knowledge, for a project Iam doing I need some information..

    Is there such thing as a proton filter? eg a device that could take in as an input different types of gas (like oxygen) and output just protons?

    if there isn't something like this, is a device theoretically possible? and any idea how much energy would be required to do so?

    Thats probably too general... but any help would be ace!!
     
  2. jcsd
  3. Jun 2, 2008 #2

    Borek

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    Are you looking for a filter, or for a proton source?
     
  4. Jun 3, 2008 #3

    Gib Z

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    I suppose you might be satisfied with a chemical reaction taking in reactants with a product being a strong acid. Acids contain Hydrogen ions, which are essentially lone protons.
     
  5. Jun 3, 2008 #4
    @ Gib Z : either you didn't get him, or you were being lame.

    @author of thread.... search up about anode ray tube experiment.. that should give you some leads.
     
  6. Jun 3, 2008 #5
    I'm looking for a filter/vacum that would output only protons, given any sort of gas.
    Thanks for your help spidey, yeah the anode ray tube is kind of what I'm looking for..

    Ok what I'll say next is kind of related but in a 'outer space' context. This is highly ambitious but is something like this possible....

    (90% of particles in space are protons...generally speaking)

    a device which could take in high energy protons mix with electrons, produce hydrogen, fire out and burn as a fuel in space?? Is this wishful thinking...
     
  7. Jun 3, 2008 #6

    Borek

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    Where are you going to take oxygen from?
     
  8. Jun 3, 2008 #7
    sorry I should have made that clear, the new question I'm asking is if this process is possible in space. So taking protons from space and converting them into hydrogen..
     
  9. Jun 3, 2008 #8

    Borek

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    You have suggested you need to hydrogen to burn it out. To burn hydrogen you need oxygen, unless by burning you mean something completely different.
     
  10. Jun 3, 2008 #9

    Astronuc

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    Well the proton is simply the nucleus of a hydrogen atoms, so unless puts a proton in the storage ring of an accelerator, it will likely find a free electron from the local neighborhood and become a hydrogen atom. Now in the elemental form, hydrogen atoms like to hang out in pairs, in the form of a diatomic molecule H2. However, hydrogen is very reactive, and is most often combined with oxygen in the form a hydoxyl ion OH, or water H2O. In inorganic compounds, hydrogen is often found in hydroxides or hydrates (and numerous other compounds), and in organic forms, hydrogen is found in natural gas (methane, ethane, . . .) and petroleum.

    To obtain free hydrogen on earth, one can extract hydrogen from hydro-carbons, which is the most common method, or one can use electrolysis or radiolysis of water or other hydrogen-bearing molecule.

    http://www.chemicalvision2020.org/pdfs/h2_report.pdf

    Hydrogen cannot be obtained from oxygen or nitrogen gas, unless one bombards the nuclei with high energy neutrons, or other high energy subatomic particles, to knock a proton out of the nucleus. If thats the case, then one might as well simply collect the protons from the solar wind and neutralize them to hydrogen.
     
    Last edited: Jun 3, 2008
  11. Jun 6, 2008 #10
    Yeah my design would have a supply of oxygen for burning hydrogen..

    That is exactly the point I was trying to make, thanks alot for your help.
     
  12. Jun 6, 2008 #11
    Dankelly, this is certainly a very original idea. And at the moment I cant see a reason why it should not be feasible, at least in theory.

    However, I doubt that you could sell it to NASA. Hydrogen (H) has an atomic weight of about 1, oxygen (O) an atomic weight of 16. So water (H20), the product of burning hydrogen, has an atomic weight of 18. So the hydrogen has only a 11% part of the total weight, so saving 11% of the weight is all you could achieve with your idea. For a practical application, this would be partially compensated by the additional weight of the device you would need to collect and process the hydrogen from space.
     
  13. Jun 6, 2008 #12
    Furthermore, then one's propulsion would be entirely dependent on proton density (assuming there were even enough ambient protons to make sufficient fuel). This inconsistency in fuel levels could potentially wreak havoc with any precisely calculated flight path.
     
  14. Jun 6, 2008 #13

    Astronuc

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    This is a key point - how much hydrogen and at what rate one can collect it? Then compare that to the propellant consumption rate.

    There have been proposals for spacecraft with large magnetic fields (something like a magsail) that would interact with the solar wind (transfer of energy/momentum) and with an onboard propulsion system, used the collected hydrogen as propellant, without oxygen necessarily.

    A H2-LOx system would need liquid oxgyen and a cryogenic storage system, and this adds mass. It would be preferable to simply use the H2 and use a solar or nuclear power system without the addition of LOx.
     
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