Cheaper Hydrogen Production

Discussion in 'General Science & Technology' started by ghost7584, Jun 9, 2005.

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  1. ghost7584 Registered Senior Member

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    I thought of a way to produce hydrogen much cheaper using less electrical energy.
    Practical Hydrogen production:
    Use radioactivity to change water into hydrogen peroxide [H2O2], then use electrolysis to change the hydrogen peroxide into hydrogen and oxygen. It should take less electrical energy to change H2O2 into hydrogen and oxygen than it does to change H2O into hydrogen and oxygen. Nuclear waste could be used to provide the radioactive material to do this. The hydrogen and oxygen separation facility could be placed close to a nuclear power plant. The cooling water that is used to cool down the atomic pile is subjected to high levels of radiation, and some of that must be changed into hydrogen peroxide. Run the cooling water from the nuclear power plant to the hydrogen and oxygen separation facility. Separate the hydrogen peroxide from the water (if you can economically do that), and use electolysis sending electrical energy into the hydrogen peroxide and separate that into hydrogen and oxygen. If you can't sepearate the H2O2 from the H2O, then use the electrolysis on the mixture; it would still take less electricity for separtation because some of the electrical energy is going to go into H2O2 molecules.
    Without using a nuclear facility you could just put radioactive waste into a large pool of water. Allow the radioactivity to change the water into hydrogen peroxide, and then separate the water from the hydrogen peroxide, and do the electrolysis on the hydrogen peroxide, separating it into hydrogen and oxygen. This should make hydrogen a practical fuel to use in engines world wide, making both hydrogen and oxygen much cheaper to produce.
    [As far as energy is conscerned, H2O2 is like an intermediate energy stage before you get to water. It should take much less electrical energy to convert that to hydrogen and oxygen. The energy from the radioactive waste is totally free, provided by the nuclear decay of the radioactive material.]
     
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  3. cato less hate, more science Registered Senior Member

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    uhhh, how does radioactivity turn h20 into h202? I am not a chemist, but I don’t see how it would happen.
     
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  5. ghost7584 Registered Senior Member

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    Radiation can directly interact with a molecule and damage it directly. Because of the abundance of water in the body, radiation is more likely to interact with water. When radiation interacts with water, it produces labile chemical species (free radicals) such as hydronium (H.) and hydroyxls (.OH). Free radicals can produce compounds such as hydrogen peroxide (H2O2) which subsequently exert chemical toxicity.
    http://radiologyresearch.org/radiationsafety/rso_fot_chapter_2.htm

    Radiation is alpha (2 protons and 2 neutrons), beta (fast electron), gamma (electromagnetic radiation)
    It looks like an alpha particle, knocks a hydrogen atom (which is a proton with an electron orbiting it) off of the H2O molecule, changing it to an OH and an H. These free radicals (highly interactive) react with H2O molecules, changing them to H2O2. That seems to be the mechanism based on what I read from that article.
    A long time ago I heard that hydrogen peroxide poisoning is a part of radiation sickness.
     
    Last edited: Jun 10, 2005
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  7. cato less hate, more science Registered Senior Member

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    you don't need to explain radiation, just the chemical part. I took chemistry, but physics was more my strong point. I guess that makes sense though. but you may as well not separate the water and h2o2. it would probably be cheaper to just do electrolysis to both, they will both produce hydrogen. By the way, an alpha particle is a helium nucleus (2 protons and 2 neutrons), not a hydrogen nucleus.
     
  8. Nasor Valued Senior Member

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    ghost7584: your scheme would work, but there’s one problem – you have to expend energy to create the radiation. In fact, if you do the calculations you will see that the amount of energy that you save in making the hydrogen from H2O2 rather than H2O will be exactly the same as the amount of energy that you put into your radiation!
     
  9. cato less hate, more science Registered Senior Member

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    he is talking about using nuclear waste to do it, and thus kind of get the radiation for free. I think
     
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  11. ghost7584 Registered Senior Member

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    Yeah, I thought about that, the separation is not needful. You can put the electrodes close to the radioactive material where the H2O2 would probably be more concentrated.
    If OH interacts with H2O, to form an H and H2O2, then you would get 2 hydrogen atoms released every time an H2O2 molecule is produced, without using any electricity. The first when the H is knocked off the H2O, and the second when the OH and another H2O combine to produce an H and H2O2. So just by having the radioactivity acting on the water it should produce Hydrogen automatically, without needing any electrolysis.
     
  12. ghost7584 Registered Senior Member

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    You don't put any energy into the radiation. The energy from the radiation is free energy. It is supplied by the conversion of mass to energy as the radioactive waste decays. What you would be doing is using the energy from the radioactive decay to assist in the splitting of the hydrogen and oxygen. You might consider this a fundamentally new way of using nuclear energy. Instead of using the heat it produces, you would be using its energy to produce a hydrogen/oxygen fuel.
     
  13. Trilobyte Registered Senior Member

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    Sounds good, but I would make sure only alpha/beta/gamma radiation is used instead of neutrons (if possible) to ensure that only chemical and not nuclear changes occur so that you are not producing radioactive hydrogen and oxygen, then burning this to produce and release radioactive water( which to me seems worse than some extra co2 or sulphur dioxide). The good thing is nuclear facilities could pay you to deal with their waste at a lower cost than is currently required.
     
  14. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    I am a physicist, not a chemist, so I probably should not comment. As I recall the Ph of water is 7. I also recall the the Ph of any solution, water included, which is all I am talking about, is by definition the negative log (base 10) of the hydrogen ion concentration per liter. That is in a liter of pure water, there are 10^7 free protons in solution (and since water is electrically neutral) there are also 10^7 negative OH ions in each liter. (Please any chemist out there correct me if I am wrong.)

    You appear to think that free protons (hydrogen ions) will some how bubble up if the water is subjected to high energy flux. Assume that you could produce an order of magnitude increase in the free hydrogen ion concentrations by this energetic flux. I.e. make both the H and OH concentrations 10^8/ liter. It seems more reasonable to me to expect that having distorted the natural equlibrium concentrations the main effect produced would be a compensating increase in the rate that H and OH recombine to make H2O again.

    I doubt very seriously that there is any significant hydrogen gas bubbling up from the water that is sometimes used as convenient shielding about small reasearch reactors ("swimming pool reactors"). I know that this water is in intense energy flux. I have seen with my own eyes the lovely Chernkov radiation in it while standing on the platform above the reactor.

    As I recal there were not any "no smoking signs" arround. Hydrogen production by your proposted method seems very far fetched, but what do I know? - I am not a chemist. Do you have any reason, other than hope, to think significant hydrogen gas can be produced from old fuel rods stored in large water pools (as they commonly are today, while environmentalist block the development of safer storage means?)

    I say "safer" because there are many of the temporary fuel rod storage pools scattered around the country, approximatel one for each nuclear plant as just getting permission to ship the old rods to a reprocessing plant is tough. It would certainly take less than the 7/11 terrorist group to attack some power plant's spent fuel rod storage facility and pull out all the fuel rods and burn them up to make the area radioactive. Only a few would even need to be willing to die. - You can put your hand on a new fuel rod with no serious radiation damage to yourself (I don't know if this is true about spent rods.) You must wear gloves if you touch a new rod - the gloves are to protect the rod from your sweat, not to protect you. - They are much too thin to provide any shielding.
     
    Last edited by a moderator: Jun 11, 2005
  15. ghost7584 Registered Senior Member

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    I am not suggesting that hydrogen is going to bubble up caused by any energy flux. I am suggesting that it would happen if the water is exposed to alpha radiation. It is Alpha that causes this reaction. What you are saying about the water surrounding the small research reactors does not apply to this argument. There is NO alpha radiation escaping into the water surrounding those reactors. [Alpha can be stopped by thick cardboard or something similar.] No alpha is escaping the metal container of the reactor.
    For this to work, you need a high alpha radiation source, like radium, and it must be in direct contact to the water. It can't be in any container. The reaction of producing the free hydrogen and the hydrogen peroxide will probably happen within 2 inches or so away from the alpha radiation source. Any electrodes for electrolysis on the hydrogen peroxide, should be placed close to the alpha radiation source, where the H2O2 is more concentrated.
    Use a nuclear waste material that is a high alpha radiation source and expose it directly to the water. It can't be in a container.

    According to this article, the situation is not as simple as you state:
    Radiation can directly interact with a molecule and damage it directly. Because of the abundance of water in the body, radiation is more likely to interact with water. When radiation interacts with water, it produces labile chemical species (free radicals) such as hydronium (H.) and hydroyxls (.OH). Free radicals can produce compounds such as hydrogen peroxide (H2O2) which subsequently exert chemical toxicity.
    http://radiologyresearch.org/radiat...t_chapter_2.htm

    Alpha radiation acting on water does produce hydrogen peroxide, which is one of the poisons that causes radiation sickness. It looks like the alpha particles energetically tearing the H2O molecules apart, is producing H2O2. During the production of this, one of the OH is lost to the H2O2 molecule and is no longer free. You would now have more free H than you have free OH, so it is out of balance and cannot just recombine faster to go back to H2O.
    According to this there should be hydrogen gas produced.
    Anyway, even if there is not significant extra Hydrogen produced by the radioactivity, the energy from the radioactivity producing the H2O2 will help reduce the amount of electricity needed to separate the water into Hydrogen and Oxygen. So you should still get cheaper production of hydrogen and oxygen using electrolysis on the H2O2.
     
    Last edited: Jun 11, 2005
  16. ghost7584 Registered Senior Member

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    The radioactive materials, that do spontaneous fission, are usually very heavy metals, or isotopes of heavy metals. I never heard of radioactive hydrogen or radioactive oxygen, two light gasses. (Double wt. and triple wt. hydrogen are not radioactive; not fissile.) Never heard of radioactive water either. There can be radioactive compounds in water, but the water itself is not radioacative.
     
  17. Trilobyte Registered Senior Member

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    Radioactive hydrogen (tritium mostly) is used for the longer term equivalent of carbon dating - so it does involve some measurable decay (eg beta decay). Oxygen can be even more radioactive than hydrogen. Fission will occur in any unstable isotope given time or stimulation. Also whether or not these elements are chemically combined ( making water) makes no difference to the radioactive properties.
     
  18. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    I'm sure you have an error here. I don't recall exactly, but the half life of tritium is something betwee 10 and 20 years while that radio active carbon (C14 - think is the unstable isotope) is hundreds, it not thousands of times longer. Tritium is a gas and this also makes it much less useful for radioactive dating - It easily migrates form the material you want to date. I am too lazy to look up the half lifes, but if you do, you will see that I am basically right.

    Your "most tritium" is also miss leading if detrium is stable, and I think it is, or at least it has a very long lifetime. There are only these three isotopes of hydrogen

    Please Register or Log in to view the hidden image!

    , pn, & pnn where "p" is a proton and "n" is a neutron.
     
  19. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    Good, we agree on this.
    Until provided with some evidence I have my doubts about it bubbling up even in a rich alpha flux. I tried to read your only reference but my browser reports that site does not exist. Please see if it does for yours.
    Here we agree also -I.e. certainly the alpha particle can rip appart any chemical compound. Where we may have serious disagreement is about what is likely to happen to the fragments produced from that "ripping apart." It even seems possible to me that some collisions of alpha partice with H2O may produce three separated atoms (H & H & O). Certainly many will produce only two (H & OH) - the same pair that have equlibrium concentrations in pure water of 10^7 per liter. I suspect that in the "three atom case" (H & H & O) the O rapidly does make OH with one that is near by and free (probably not either of the two Hs that were produced by the alpha collision as there is a lot of momentum to be conserved and the three (H & H & O) will be blasted considerable distance apart - I.e. their initial "recoil" will almost immediately cause secondary collisions with other H2O molecules (some of these secondary collisions may do more chemical splitting of H2O - like muons in a cosmic shower increasing in total number as they lose energy in secondary collisions.) That is, if initally three three atoms are produced, they will "quasi random walk" away from each other and hence (I think) when the O takes a new H partner to become OH radical (a negative ion) it is likely that H is one of the 10^7 /L already there, not the H that was freed in the alpha collision.

    Note the three separate atoms case is less probable that the two separate (H & OH) case and even when (H & H & O) is produced, the fragments rapidly (in microseconds I bet) convert to the two only (H & OH) case. Thus the best you will do is to increase the natural concentration (10^7/L) to something like 10^8/L max. Probably much less as the rate alphas are produced by the mix of radioactive isotopes in old (spent) fuel rods is very much less than the rate the natural 10^7/L concentrations of H &OH are recombining. Summary of this point: Your alpha particles will not change significantly the concentration of positive H ions and negative OH ions. (See later section to learn how you can dramatically and cheaply increase the H ion concentrations.)
    I think you do not understand electrolysis very well. In this process, as you do know, two electrodes and a DC current are used. The electrodes establish an electric field in the water and this electric field gives a net drift to the natural Brownian motion (a random walk with much faster speeds than the induced drift) of the charged particles (the ion content only) in the water. The electric field exerts no force on the neutral H2O2. The electrolysis will be only slightly more efficient if you can increase the concentrations of charged particles = ions in the water. I just explained why the low rate of alpha production from spent fuel isotopes will produce little change in the concentration of these ions.
    Here we agree also, (except for your "high alpha source"), but I for one would be very opposed to taking the mix of radioactive isotopes found in spent fuel rods out of their containment cases and making a water solution of them (Most would have little solubability in water so you would need to grind into a fine powder and constantly stir your "alpha particle/ electrolysis tanks.) The expense of grinding a mix of radioactive isotopes, without air release, would very likely greatly exceed the economic value of you might obtain via your postulated increased efficiency of electrolysis - which I doubt is even real. Thus you should not expect any economic advantage for your proposed process but should expect "regulatory headaches" beyound belief, from "enviromentalists."

    In the current world, I would be very opposed to your mix of water and radioactive isotopes in solution and as particles stired to prevent settlement to the bottom. All a terrorist need do the spread fear and great economic loss would be to toss a stick of Dynamite into the pool, like some people do when illegally "fishing." Summary: Your idea appears ill-founded and very dangerous.

    That may be true, but as H2O2 is not charged it will not directly participate in the electrolysis. It and many other things you can add to pure H2O will shift/change the Ph from 7. If you want to use something that is a waste product, why not old battery acid? That I know will make a big change of Ph. I.e. greatly increase the H ion concentration, easily by a factor of 1000. I am no expert on electrolysis, but I think that is what is actually done to increase the water conductivity, H ion concentration.

    The generator in your car, if the voltage regulator fails, will do electrolysis very well on the acid solution in your battery.
     
    Last edited by a moderator: Jun 11, 2005
  20. ghost7584 Registered Senior Member

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    I went an researched about radioactive hydrogen and oxygen on the web.
    Oxygen is no problem at all. Radioactive oxygen is only produced by the extremely high energy of a cyclotron. It would not be produced by radioactive substances in water.
    Radioactive hydrogen is only in the form of tritium. It is supposed to be rare. It is produced by neutron bombardment of heavy water (deuterium oxide) or Li6 in a reactor. The ammount of heavy water occuring naturally in water is very small. If any tritium would be produce by having the radioactive substance in the water, it would only be minimal and not a problem. Also tritium only decays into a weak bata particle that can't go through paper. It also occurs naturally already in the air by cosmic rays acting on deuterium.
    It looks like a very small and insignificant amount of radioactive hydrogen would be produced, and it should cause no serious problems.
    Also, perhaps the neutrons could be controlled in some way to help stop thelm from entering the water, or you could use a radio active source that is high in alpha radiation and produces no neutrons.
     
  21. ghost7584 Registered Senior Member

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    Got this from the web:
    Secondary reactions occur after free radicals have been produced in the irradiated water. The free radicals want to combine with other free radicals to become more chemically stable. There are three possible combinations: 1. A hydrogen free radical combines with another hydrogen free radical to produce hydrogen gas. Cells already have a measureable amount of dissolved hydrogen gas present so this reaction has little impact. 2. A hydrogen free radical combines with a hydroxyl free radical to produce water. As we know, the introduction of another water molecule is not a problem. 3. A hydoxyl free radical combines with another hydroxyl free radical to produce hydrogen peroxide. If you think this sounds harmful to the cell you are right! The hydrogen peroxide is poisonous to the cell as well as the peroxide radicals that can be formed which in turn attack other bio-organic molecules to form stable organic peroxides. The organic molecule that was attacked may have been imperitive to the cell's cycle and is no longer available for utilization, eventually causing the cell's death.* *Source: Basic Radiation Protection Technology, 1994.

    Since two OH combine to form H2O2 instead of an OH and an H2O like I thought, it would only produce half of the hydrogen from the radioactivity alone than I thought.
    [The accident at Chernobyl was precipitated by a hydrogen explosion. They used a different type of reactor.]
    It was pointed out to me by several people that it takes a lot of electrical energy to split the H2O molecule into hydrogen and oxygen and this is one of the major problems with producing hydrogen fuel. I decided, use the free energy from radioactive decay to change the water to hydrogen peroxide and then use less electrical energy to split that into hydrogen and oxygen. That is the original idea. This would make the hydrogen fuel practical, whereas now it is not practical.[Water is a highly stable molecule; hydrogen peroxide is not. Less electricity should rip it apart.]
    Whatever they use for increasing the conductivity for water electrolysis would probably also work with H2O2 electrolysis.
    The idea is that you are using some free energy from nuclear decay to assist in the tearing apart of the water molecule. So you need less electrical energy to do it. This makes hydrogen fuel really practicle.
    Working out the details of how to really do it would require experimental trial and error, like working out the details of anything else.

    I am not suggesting mixing the isotopes in a powder and water form. I am suggesting putting them uncontained in the water in whole pieces, and placing the electrolysis electrodes close to them where the hydrogen peroxide should be most concentrated. The shielding is provided by the water. [I think you need something on the order of 150 pounds of anything per square foot, for shielding?]
    Half life of tritium is 12.5 years. Deuterium completely stable.
    Radioactive oxygen produced only by cyclotron.
    Insignificant amount of tritium should be produced. Only decays into a weak Beta particle anyway.
     
  22. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    To Ghost 7584:
    I don't want to discourage you from thinking (dreaming?) about new ways to use, generate, and/or store hydrogen. I am glad you are turning to the web to get some of the facts straight, but you need to do a lot more of this still.

    I am too lazy to look things up there and tend to rely on my memory for information. I knew tritium would not be a problem in your scheme and only remembered it half life was more than 10 and less than 20 years (Thanks for informing me it is 12.5)
    The only reason I mentioned it is you erroneously said it could be used to make radioactive dating of objects older than radioactive carbon could. (I still don't recall the half life of c14, but am almost sure it is at least 1000 times longer than tritium, so I knew your claim for it "reaching farther" back into the past than tritium was erroneous.
    C14 is continiously produced by cosmic ray hitting CO2 in the high atmosphere. It is especially useful for dating old bones because animal's bodies treat the normal, stable, C12 and the radioactive C14 exactly the same (in their chemical food processing).
    The continuous production and decay of C14 establishes a fixed concentration of C14 in the air (assuming the atmospheric CO2 and cosmic ray flux remains constant). I.e. the ratio of c12/c14 is fixed and known. I don't know what this ratio is, but lets guess it is 10 million. That means two of every 20 million carbon atoms in the animal's body on the day it dies (stops eating grass or meat etc = stops its intake of carbon). If one finds some old skin or bones and measures that, for example, there is now only 1 c14 for every 20 million C12s, then one knows that from the day it died until now, one half life of C14 has passed. We can now agree to say no more on this issue (but if you trouble to find the half life of C14, tell me.)

    I will respond to your most recent post about using H2O2 for electrolysis in separate post.
     
  23. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    Your first paragraph, taken from web source, which I have not reproduced above, appears basically OK. I am sure that ordinary water ("pure water") is not just H2O molecules. I have several times told that in each liter of water there are 10^7 H ions and 10^7 OH ions. I don't know the number, probably it is less than 10^7/ L, but I am sure there are some electrically neutral H2O2 molecules as well.

    The electrical neutral molecule H2O2 does not move towards either electrode in an electrolysis cell. Only charged ions move under the influence of the applied electric field. Thus, I have little reason to think that your basic idea:
    "to change the water to hydrogen peroxide and then use less electrical energy to split that into hydrogen and oxygen."
    is a correct idea. I can guarentee you that if you could put electrolysis electrodes in truely pure H2O2 (i.e. a non-existent liquid with only H2O2 molecules present - no H or OH ions, etc.) then no current would flow between the electrodes and ZERO Hydrogen would be produced.

    Your hope/ wish / dream to the contrary, does not cancel this physical fact.

    I don't know if it is easier or harder to split H2O2 than H2O. All I know about H2O2 is that it is reactive (used to bleach colors out of cloth etc.) and that it has consider energy that can be extracted becaues it is reactive. - In WWII, the germans used H2O2, as fuel in some of their submarines, instead of electrical batteries, to run below the water surface without a "snorkel pipe" above the surface (without exposure to RADAR). You can surely drive a car on H2O2 fuel. You will spend energy to make hydrogen from H2O2. You can drive a car on H2O2, without this expenditure of energy (and you never recover 100% of the energy you expend to make Hydrogen from anything) The fact that H2O2 can be used as a fuel, has been known for at least 100 years. It is not attractive, and less attractive after passing thru your scheme, even if your scheme would work! (You need to do more research and a little less dreaming. In another post I will give you an idea that may have some merit about hydrogen, but I doubt it and have not explored it much. - I'll let you do that if you like.)

    I am no chemist, but bet it is true that it takes less energy to split H2O2 than H2O, but this would make no difference in your scheme. The alpha particle has at least a million times more than the required energy for splitting either. To give you an analogy: Suppose you want to smash ants and there are big strong ants and small weak ones. If your smashing tool is a feather, then it may make a difference which type of ant you try to smash. If your smashing to is a wrecking ball droped from 100 meters above the ant, then which type of ant your are smashing makes no difference. The alpha particle is like a wrecking ball, not a feather, when the task is to break apart any chemical compound.

    You said: "Chernobyl was precipitated by a hydrogen explosion." This is incorrect. The "accident" may have ended this way, I forget if there was a hydrogen explosion or not. I may be confusing the fear of one at three mile island - which as I now understand it was baseless, but a very real fear for a day or two at the time.

    What participated the Chernobyl event, was really the cold war and in some sense the US should shair some of the blame for the accident. The russian were afraid US would conduct a "preemptive strike." (A doctrine Presendent Bush supports even today.) They needed to be able to have enough nuclear weapons to be confident that they could survive a first strike and still make it so costly for the US to make a "pre-emtive first strike", which was publicaly advocated by many, especailly before the Russian set off their first hydrogen bomb and the US had Hydrogen bombs, that the US would not make as first strike. I.e. both sides adopted the "MAD policy" (Mutual Assured Destruction)

    As is the case today with North Korea, the Russian (USSR) government (via its physicists) knew that the quickest way to get material for nuclear bombs is to run a nuclear reactor desiged to produce as much pultonium as possible; I.e not one designed for efficient production of electric power. Unfortunately, most if not all such "plutonium production reactors" have what is called a positive temperature coefficient. The one built at Chernobyl certainly did. It was designed to make plutonium the ussr needed for MAD.

    A positive temperature coefficient reactor can be run safely. If the temperate goes up alittle and the reaction rate increases as a resullt, you jsut put the neutron absorbing "control rods" in a little deeper. Likewise if the reactor core coolant is at 200 degrees C,(in pressure pipes and still liquid that when the pressure is redced will flash into steam for the turbins driving the electric generations - I am omitting the heat exchanges that are always used, even at Chernoble) and you pull the control rods out a little, immediately the reaction rate will increase (essentailly step like increase) and then more slowly the temperature of the core will increase. Because the design has a "positive temperature coefficient," - the reaction rate will have a slow increase as the core temperature increases.

    Even at Chernoble, there were automatic controls that increase the coolant flow to prevent the temperature from increasing and causing the reaction rate to increase. The "engineers" running the reactor on the night of the "accident" wanted to measure the temperature coefficent and these automatic controls were frustrating their efforts, so they shut them off.

    The plan was to pull the control rods out a little, note immediate step up in power production (reaction rate) and them watch the realtive slow increase in reaction rate increase caused by the relatively slow increase in temperature of the core. After the tempurture and reaction rate increase caused by the the temperature rise had been measured, they planned to plunge the control rods back in deeply and essentially kill the reaction rate. This experiment was done late at night when the suddend drop in power from Chernble reactor could easilly be compensted by incresed electric power production at other reactors and thermal power plants.

    I am not sure what went wrong, perhaps no one is. A very good possibility is that some of the fuel rods got so hot that the passageway for control rods was partiallly blocked, perhaps by pieces of fuel rod case that had come off or loose with the excess thermal heating of the rods. In any case, they could not "crash" the reactory as they had planned and the rest is history. - With a positive thermal coeficient, it entered a "run away" mode and parts of the core melted. etc.

    I will conclude this post with a few words about your statement:

    "I am not suggesting mixing the isotopes in a powder and water form. I am suggesting putting them uncontained in the water in whole pieces..."

    As you correctly observed in another post, alpha particles don't penetrate much. Thick alumium foil will stop them. Even thiner foil of heavy atoms will also. Most atoms in the spent fuel are heavier than aluminum. Thus if you want a significant fraction of the alphas produced by the radioactive decay of the spent fuel to enter the water, your "pieces" should have diameter significantly smaller than the thickness of aluminum foil. That is, what i'd call a "powder," but if you want to call it "pieces," I will not object.
    The point was the fuel rod is full of "pellets" about a centimeter in diameter and/ or length and you must grind them up to get your "pieces" (my "powder"). The cost of doing this, with the care that environmentalists would demand to avoid any air born release of radioacive dust, is so high that even if everything else in your process were absolutely free, I bet your hydrogen fuel would be at least 100 times more expensive than gasoline on an equal energy content basis. (when nuclear power plants were first being designed and no one realized how many years the environmentalist could delay/block construction the plan was to charge a low fixed rate for the power (big house pay more and factories would be metered if they used a lot of power.) This was because for the typical house, the capital cost of the meter would be more tha the cost of the electricity the house used. "Too cheap to meter" was the phrase that was used, before the economic impact of the environmentalists was understood.
     
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