[Seeker]

quote:Originally posted by yop

Sodium borohydride is a hydrogen storage strategy. It's a safer alternative to transporting hydrogen under pressure in a cylinder. Unlike compressed hydrogen gas, sodium borohydride won't explode on you. The drawbacks are cost and the fact that sodium borohydride is a solid, which makes it harder to handle. For example, you can't pump it from place to place, like gasoline or hydrogen gas. Note that sodium borohydride has nothing to do with the original hydrogen generation. You still have to generate hydrogen somehow so that you can then synthesize sodium borohydride from borax and hydrogen.

Xogen's patent describes a hydrogen production strategy, generating hydrogen gas from water using electricity. Short powerful pulses of electricity should be more efficient than a continuous lower level of power. First, the periods when there is no electricity flowing gives the evolved gases a chance to get away from the electrodes, so you don't waste power by putting it into the hydrogen or oxygen gas bubbles that collect on the electrodes. You want the energy to go into water molecules to generate more hydrogen gas, instead of going towards heating up the hydrogen gas that you generated earlier. Second, a short powerful burst of electricity helps to minimize losses to the bulk water in the vessel. Ideally, you would put all of your energy into one O-H bond at the electrode until it broke, then move on to the next, etc. In reality, however, the energy that you put into the system at the electrodes is constantly bleeding away into the bulk water, heating it up. Eventually, that will give you steam, instead of the hydrogen gas that you want. Short powerful pulses help push the kinetics towards hydrogen gas instead of steam.

All that being said, I think that much of the Xogen patent is a load of BS. It talks about "ortho" and "para" hydrogen, which supposedly differ in their chemical properties because their nuclei have different spins. But nuclear spin has next to zero effect on chemical activity, as far as I know. Electron spins can have major effects, but not nuclear spins. My guess is that this ortho and para hydrogen junk is just a smokescreen to help them get around an existing patent.

Hi yop,

Thanks for these good insights. With the sodium borohydride, as I'm understanding it, this would be dissolved in water, and the solution could be used in much the same way as gasoline.Am I wrong about this ? As far as the ortho and para hydrogen goes, it sounds like these 2 forms have different physical properties, such as stability,boiling point,and thermal conductivity, however, their chemical properties are the same. I seem to recall that the Xogen people were claiming that one form of hydrogen was slow burning ,while the other was explosive... Hmmm?

Seeker