How do I remove nitrogen from air?

  1. Hi All, Is there a type of airfilter!! that will remove nitrogen from AIR??

    if not can I force air through water to remove nitrogen?? If not

    How do I remove nitrogen from AIR

    Please keep it simple as I is STUPID

    goony
     
  2. jcsd
  3. chroot

    chroot 10,426
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    The typical way is to cryogenically liquefy air, and take advantage of the different boiling points of the different gases to separate them. You're not going to have any luck with a filter.

    - Warren
     
  4. Do you mean that by freezing air the nitrogen removes itself? during the freezing process

    goony
     
  5. chroot

    chroot 10,426
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    No, I mean that nitrogen and oxygen (and argon, etc.) boil at different temperatures. There's no freezing involved, only the phase change from liquid to gas.

    - Warren
     
  6. mgb_phys

    mgb_phys 8,952
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    To explain further, when you cool gases they turn into liquids - just like when you heat liquids the turn into gases (for example boiling water to make steam)
    To turn air into a liquid you have to cool it a lot ( -196deg C / -320F ), this takes a serious piece of industrial equipement.

    Then because nitrogen and oxygen turn into liquids at different temperatures you can heat the liquid air up until one of them (oxygen first) boils off, you ae then left with nitrogen, as chroot described.
    This is called distilling and is exactly the same process as boiling off water to keep the alcohol when making whiskey - that's why they are called distilleries.

    On a small scale you could also find some chemical that reaction with nitrogen but not oxygen and have that 'use-up' all the nitrogen in a sample, leaving just the oxygen. I can't think of anything suitable - most things react with oxygen better than with nitrogen.
     
    Last edited: Jun 27, 2008
  7. chemisttree

    chemisttree 3,721
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  8. Borek

    Staff: Mentor

    To some extent you may remove nitrogen using molecular sieves.

    Edit: looks like chemisttree beat me by 1 minute :frown:
     
    Last edited: Jun 27, 2008
  9. I have been working on a project for some time now. In cars gasoline is wasted because it is not fully atomized. The air mixture is mostly components that are not concentrated enough to ignite (Hydrogen) or inert components that are of no use (Nitrogen). The Oxygen content limits the reaction in it's current percentage.

    I've found that if you cool air that the process of simple dehumidification increases the efficiency of the combustion process. If that air is compressed and sent in through a sealed air-fuel mixture chamber there is further efficiency but less than I expected but it's still impressive.

    To describe it, think of trying to boil and egg in Colorado and then do one in Arizona. If you measure the energy spent for the outcome that is the result I demonstrated. O.K.- now that I've demonstrated that I passed the 3rd grade here is my question. Is there a way - using components currently on a vehicle (as I have done) to further enhance the oxygen to the engine?
     
  10. If one were able to safely compress and then decompress purified and dehumidified air would that be possible on a microscale in a lab?
     
  11. Q1: "How do I remove nitrogen from AIR"

    Q2: "Is there a way - using components currently on a vehicle (as I have done) to further enhance the oxygen to the engine?"

    The "Pressure Swing Absorbtion" method mentioned above is actually simple enough. it is used in oxygen makers used for medical purposes. It uses a compound called "Zeolite" to absorb (and remove) Nitrogen from air. At some point the compound becomes saturated and needs to be regenerated using heat.

    Waste heat from the exhaust and catalytic converter could be used to regenerate the zeolite intermittently. Since it is a cyclic process, you could use 2 or more scrubbers. One would be in use at all times, while the other(s) are regenerating.

    The "Pressure Swing Absorbtion" process also involves pressurization of air. As you mentioned, this alone leads to a small increase in efficiency. Combined with pure oxygen, it would be a large increase.

    An engine equipped with this system would not produce Nitrogen compounds formed during combustion as air respirated angines do. The expelled nitrogen could be mixed with exhaust gas downstream.
     
  12. my QUES is at WARREN:
    hi sir!
    How de we remove nitrogen from air at NORMAL ATMOSPHERIC CONDITIONS? ( Usin any air filter?) Pls reply
    shall v use LITHIUM COATIN
     
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