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Burning salt water for fuel?

  1. Sep 11, 2007 #1

    Evo

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    Does anyone think anything will come from this?

    http://news.yahoo.com/s/ap/20070910/ap_on_sc/burning_seawater [Broken]
     
    Last edited by a moderator: May 3, 2017
  2. jcsd
  3. Sep 11, 2007 #2

    LeonhardEuler

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    I saw this in the news and searched here to see what has been said about it:
    https://www.physicsforums.com/showthread.php?t=172018&highlight=water+burn

    It seems that what's happening is that the RF beam separates the water into H and O, which is then combined back into water in a flame. Of course, you wouldn't get any energy out of the process: you have to use more energy in the RF generator than is given off as heat over the flame. I'm surprised how no one mentions this in the article. It seems clear that this process can not have a net generation of useful energy.
     
  4. Sep 11, 2007 #3

    Chi Meson

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  5. Sep 11, 2007 #4

    Evo

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    Thanks, nothing came up when I searched.
     
  6. Sep 11, 2007 #5
    Actually, it would have fantastic potential as a desalinization method. The burned H and 0 would be pure water and the heat generated could be used to help generate more radio waves.
     
  7. Sep 11, 2007 #6
    OH NO I just filled my gas tank up with salt water and strapped an old radio to it.:cry:
     
  8. Sep 11, 2007 #7

    Kurdt

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    I've been constantly amazed in all these water energy claims how nobody ever mentions the fact that one needs energy to split the molecule and unless your process is 100% efficient you will lose energy. There is no way you will ever gain any. The same with perpetual motion machines. Unless the process is 100% efficient it can't be perpetual and even then if you extract energy from the system it will eventually stop. So whatever is used to set the thing off may as well be used as the source of energy generation.
     
  9. Sep 11, 2007 #8

    Evo

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    Disclaimer: PF is not responsible for news articles linked to from this site.

    On the positive side, you now have a musical fish tank.
     
    Last edited: Sep 11, 2007
  10. Sep 11, 2007 #9

    You may just have something there. From salt water to fresh water in a flash. And solar could also be used to generate RF.
     
  11. Sep 11, 2007 #10

    Astronuc

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    I cringe when I see headlines like that. It's the hydrogen that burns, and the hydrogen comes from dissociated water. Electrolysis has been used to achieve the same result, so I don't see this as a necessarily new discovery.

    I imagine there's probably some chlorine gas and HCl around as well, and with H gone, the water would become more alkaline.


    I imagine the energy lost producing the microwaves and then lost in the dissociation process make for an inefficient process. The objective for hydrogen production is to have a fuel that can be transported or used in a tranportation process. Burning hydrogen at the source would be a wasteful use of energy. It would make more sense to collect the hydrogen in an inert carrier gas for storage or chemical synthesis.

    The overall scheme might be worthwhile if solar energy is used as the top level source of energy, but converting solar energy to microwaves may not be practical.

    Roy has been around a long time, and I remember his work for nuclear waste processing and waste forms from the 70's and 80's. He certainly knows how to get funding.

    http://www.rustumroy.com/
     
  12. Sep 11, 2007 #11

    Ivan Seeking

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    Geez, I jumped online and found two emails about this. Then I find two threads about it here.

    The generation of microwaves is a little over 60% efficient. Then you have the coupling to the water, and dissociation. I would bet that you would never do better than 30 or 40% efficient overall.

    Electrolysis is about 50% efficient in practice, so it seems very doubtful that this process would have an advanatage.
     
  13. Sep 11, 2007 #12

    Chi Meson

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    Rustum Roy appears to be a bona fide chemistry professor. Is he running a sham for funding? Or has he never stumbled upon the laws of thermodynamics? Or is it possible that there could be something there? Specifically, is there more than just the hydrogen burning?

    I just find it incredible that a university professor would risk his credibility on a PPM. Or am I naive?
     
  14. Sep 11, 2007 #13

    Ivan Seeking

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    Is he interested in the energy or the process?
     
  15. Sep 11, 2007 #14
    OK then I can see where this concept may show up on late night Television informercials..

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    But wait !! call now and receive a pint sized bottle of monkey urine absolutely free.

    HOLD ON!! Call In The next five minutes and also receive our free recipes for cooking with monkey urine over hydrogen

    That's the Guide book, the monkey urine plus the recipe book a $200 value for only $19.95

    CALL 1-800-EVO-HOME immediately


    am I in trouble or what?
     
  16. Sep 11, 2007 #15

    Evo

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    He seems to have a number of papers concerning microwaves. Perhaps that is his interest.
     
  17. Sep 11, 2007 #16

    Evo

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    You're in trouble, it's possum urine, monkey urine just sounds more exotic.
     
  18. Sep 11, 2007 #17
    He has a patent on: Method and apparatus for microwave phosphor synthesis
     
  19. Sep 11, 2007 #18

    You are such a good sport, :wink: I just could't resist. I'm tring to wind down from a long day.
     
  20. Sep 11, 2007 #19
    It all appears to have started with this man.



    It seems like the chlorine in the salt water might make some noxious fumes. Could it end up with some form of Hypochlorite??
     
    Last edited by a moderator: Sep 25, 2014
  21. Sep 11, 2007 #20
    Why do you think the department of defense is interested in it? Probably because it has some obscure potential as a weapon. Bullets can't go through walls, but radio waves can right? Imagine a weapon that lights enemies on fire through walls with just the use of radio waves. After all the human body is what, 70% water?
     
  22. Sep 11, 2007 #21
    Yipes, and the electrolytes in the blood are comprised of salts.
     
  23. Sep 12, 2007 #22

    Astronuc

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    Roy is a bona fide chem professor, and he is quite credible. He can also afford to stick his neck out. I am sure that he would be trying to optimize the process. One problem would be recombination, which competes with dissociation, but that could be mitigated with inert gas like Ar being pumped through the system. Then if Cl2 is produced, one has to deal with that, so the process would have to done without light present.

    As edward mentioned in his post, with an acqueous salt solution, in addition to hydrogen, one will get Cl2, ClOx (x=1, hypochorite (bleach); x=2, chlorite), maybe HCl. The ClOx compounds would stay in solution. IIRC, chlorine is produced from seawater anyway.

    Sea water has dissolved salts of which most is NaCl, with some Mg, K, Br.
    http://hyperphysics.phy-astr.gsu.edu/hbase/chemical/seawater.html
    http://en.wikipedia.org/wiki/Seawater

    Desalination of seawater is already in place in parts of the world. Saudi Arabia probably has the biggest program and the largest plant is apparently in UAE.
    http://en.wikipedia.org/wiki/Desalination
    http://www.coastal.ca.gov/desalrpt/dchap1.html [Broken]
    http://www.dow.com/liquidseps/prod/sw.htm - Dow sells membranes for reverse osmosis systems.
     
    Last edited by a moderator: May 3, 2017
  24. Sep 12, 2007 #23
    Of course energy is conserved: you can't get more out than you put in.

    Actually, that's not an accurate statement. It should be "You can't get more out than was put in." If I burn a tree, it wasn't necessary for me to physically put the energy I get out of the tree into it. The sun did most of that work. Likewise, I didn't have to physically imput the amount of joules that running my truck represents into the truck myself: the sun did most of that work.

    It isn't necessarily the case, in principle, that you can't get more out of this process of dissociating water by radio waves than you expend in generating the RF. It depends on what energy has gone into the present state of the saltwater, including whatever ambient heat it has stored. If the RF is dissociating the H20 it is probably also affecting the salts and dissolved gasses:

    From: http://www.seafriends.org.nz/oceano/seawater.htm#salinity

    If you go to the link and click on the various categories you'll see there is a complex soup of stuff here. How all this might be affected by RF and how it all might recombine, is beyond my level of chemical knowledge, but the first thing anyone needs to do is make some precise measurements of joules in verses joules out. There is some chance that salt water represents a rock sitting on a cliff edge whose energy can be harvested by a push from the RF. I know that seems doubtful, but it should be systematically investigated, rather than dismissing the notion based on the meme "You can't get something for nothing." We get energy from the sun for nothing all the time. In any case, it's an interesting enough phenomenon to investigate in and of itself, and figure out exactly what's going on.
     
  25. Sep 12, 2007 #24
    The military is already aware of the destructive properties of RF:

    http://www.safetycenter.navy.mil/acquisition/RFR/default.htm

    I'm sure it's potential as a weapon has already been thoroughly investigated.
     
  26. Sep 12, 2007 #25

    baywax

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    Is this going to work as an efficent way to separate H from O in producing hydrogen for fuel cell energy production? As was mentioned, solar can provide cheap energy for the production of radio waves

    ..... come to think of it, you don't have to plug in a crystal radio. How about using a really big one?
     
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