Let's get back basics. NaH is a material that decomposes to H2 and Na liquid containing dissolved H above 100°C. This is a process that causes the pressure of H2 to rise as temperature is increased according to the equation log P(atm) = 9.49-5070/T(K). As a result, the pressure of H2 goes from 22.5 atm at 350°C to 90.5 atm at 400°, within the region that the endothermic reaction is said to occur. At 650°, the pressure is 9932 atm, while the Na liquid contains considerable H.
Because of this behavior, a sharp endothermic reaction is not expected if the H2 is in equilibrium with the liquid, especially in the range measured. However, if the loss of H2 is inhibited, the loss rate might occur rapidly over a narrow range of temperature.
The pressure of H2 at the start of the exothermic reaction is higher than most normal devices can take. Therefore, either the pressure was reduced or a small amount of NaH was used so that the pressure remained in the safe range. This means that the liquid Na contained less dissolved H than its maximum. Unfortunately I could only find a value for the solubility of H in Na at 450°C, which is 4 atom %. The concentration increases with temperature.
So, the endothermic reaction appears to be caused either by a inhibited decomposition of NaH or a reaction with the container. My question is, what kind of material was used to contain the liquid Na during the test?
In the BLP reactor configuration, the liquid Na might fill the pores in the Raney Ni. Therefore, the gas would be in contact with Na liquid. Question, is the proposed reaction occurring between the Na(H) and Ni or between the Na(H) and H2? I don't know the partial pressure of NaH gas, but I expect it would be very low.
What are we to conclude in light of these expected behaviors? Ed On Oct 26, 2008, at 8:30 PM, Jeff Driscoll wrote:
Does someone have the capability of doing a Differential Scanning Calorimeter measurement on Sodium Hydride (NaH)? NaH can be bought from chemical suppliers where it is sold as 60% weight NaH and 40% weight mineral oil. The oil keeps air and water from contacting it and chemically reacting with it. There is no Raney Nickel involved. According to wikipedia, the oil can be rinsed off the NaH with pentane or tetrahydrofuran. Mills gets an exothermic reaction of 354 kJ/mole H2 (or 177 kJ/mole H) when he put .067 grams of Sodium Hydride in the Differential Scanning Calorimeter (reaction started at 640 C). That's 45% higher energy than the 242 kJ/mole for burning hydrogen in air - even though the sample volume had been flushed with helium twice before the start of the test. Is it possible that there was enough oxygen contamination (from leaking or whatever) to burn with the hydrogen? Could they have incorrectly measured the amount of NaH in their sample? If not, then this test (when carefully done) could be a verification method of Mills data. Just rule out oxygen contamination and weight measuring mistakes. Magnesium Hydride (MgH2) was used in a separate test and displayed the predicted endothermic reaction of decompisition and endothermic reaction of melting magnesium. Since this test didn't have oxygen contamination issues then I would assume the NaH test didn't either. look at page 21 here from BLP's paper regarding this differential scanning calorimeter test: http://www.blacklightpower.com/papers/WFC101608WebS.pdf One thing I don't understand is that there was an endothermic reaction at 350 C where sodium hydride decomposed before the exothermic reaction (hydrino creation) starting at 640 C. If the sodium hydride decomposed then all of the hydrogen has evaporated and there is no longer a NaH molecule. According to Mike Carrell the NaH molecule is necessary for the hydrogen shrinkage reaction because the breaking of the bond energy between the Na and H is involved in absorbing a portion of the 54.4 eV from the hydrogen shrinkage (along with double ionization of Na to Na++). Does the monatomic hydrogen released during decomposition recombine with another H to make H2? That would prevent the hydrino reaction. Somehow the monatomic H has to recombine with the Na to make NaH at 640 C so as to trigger the hydrino reaction. Does this mean you could coat sodium metal onto nanoparticles and expose them to hydrogen at 640 C and trigger the hydrino reaction? you can read about differential scanning calorimetry here http://en.wikipedia.org/wiki/Differential_scanning_calorimetry Jeff D.
