I have a question not strictly related with your plans: if you were to manually slowly admit hydrogen at this temperature (perhaps starting from a lower pressure level), would it be a relatively safe thing to do with your setup?
MFMP: Automated experiment with Ni-LiAlH
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Note that the temperature of the Swagelok compression connector at the end of the ceramic reactor tube is presently 56.8°C, well within the range of epoxy. The measurement is at the orange dot on the left. There are 3 holes for probes t go through the round aluminum clamping mount. The red dot is a reflection on the compression nut of the orange glow coming out of the insulated heater through the hole in the round clamp.
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can,
If I understand your question correctly, I believe you are asking if I had the plumbing to evacuate the reactor tube, and then by valve switch, admit H2 into the reactor tube, would it be safe? This is a good question to consider. I believe it would be safe - just as safe as having the H2 atmosphere in there now. The volume is less than 1mL on the reactor side of the valve and the O2 should have been largely removed. Where I do have a concern is my vacuum reservoir - about 20L. When the H2 is pulled from the reactor tube, it goes into this vacuum reservoir, which I know now is leaking air into it (yet another leak to find). So I am getting a mixture of O2 and H2 in my vacuum reservoir, along with a nice iron catalyst inside. I have the reservoir grounded and I am frequently emptying it by running the vacuum pump.
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Eventually I would like to have a gas control system that would allow me to insert H2 and D2 under computer control into the reactor tube and regulate the pressure. It would not be hard to do. I want to be able to create a script to be operating with one gas and be able to evacuate the tube and switch to the other isotope to see the effect on XH.
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you are asking if I had the plumbing to evacuate the reactor tube, and then by valve switch, admit H2 into the reactor tube, would it be safe?
Yes: I meant this, sorry for not being too clear.
In this case hydrogen admission was meant to be performed at a rate similar to that of a small leak; not all at once, but too slowly either.
At this temperature hydrogen diffusivity through the powder-fuel or any liquid layer if present should be rather high.
This is a good question to consider. I believe it would be safe - just as safe as having the H2 atmosphere in there now. The volume is less than 1mL on the reactor side of the valve and the O2 should have been largely removed. Where I do have a concern is my vacuum reservoir - about 20L. When the H2 is pulled from the reactor tube, it goes into this vacuum reservoir, which I know now is leaking air into it (yet another leak to find). So I am getting a mixture of O2 and H2 in my vacuum reservoir, along with a nice iron catalyst inside. I have the reservoir grounded and I am frequently emptying it by running the vacuum pump.
Having the gas statically contained within a closed environment is safer than making it flow from an external canister to a high temperature environent; this is the main reason why I asked. You also have to take in mind the remote possibility of anomalous or unexpected reactions causing rapid temperature increases in the system.
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Yes, there is some danger of catastrophic high temperature melting of the alumina - Zhang Hang has seen this with H2 present. These do not seem to be too explosive - which is a little surprising. My system minimizes the H2 dead volume in the system - there is less than 1mL in the whole system on the reactor side of the valve. That's why I use the small tubing. This tubing is available with 1/16" OD and 0.005" ID (tiny, capillary). The tubing is made primarily for gas chromatography systems.
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14:00 UTC graph update: round2-pdf-1491057910.pdf
It's stable.
EDIT: 15:00 UTC graph update: round2-pdf-1491060992.pdf
It would indeed be very useful to also be able to precisely control pressure and flow rate in an automated and controlled manner, once a hydrogen flow-dependent reaction has been established.
It would also be quite interesting if the alumina tube managed to melt, safety considerations aside.
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can,
Not sure why you think flow would be beneficial. The H2 flowed in would be cold and would create a tiny thermal shock, but not that much. It would also affect the power balance since the hot H2 taken out would carry away a small amount of heat.
Precisely controlling pressure and the ability to switch to D2 would be advantages of being able to regulate an inflow of gas. It is somewhat painful to control the pressure of such a small volume of gas. As it is, I have a 10 micron orifice at the outlet of the valve to control how fast the gas can escape to limit the overshoot due to the valve open/close time - and it still overshoots. It can be done a little better, but it is OK for now. Mostly I wanted to mimic Parkhomov's pressure vs. temperature curve which he got by having a leak - so I figured I needed a computer controlled leak (the back pressure regulator).
I have turned off the back pressure regulator because the system should no longer need regulation to mimic Parkhomov. This also allows me to leave the vacuum pump off which is really a pain to mind since it is manual at the moment.
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Without going into details about why *I* think it could be beneficial, have a look at these excerpts from one of Piantelli's granted patents:
Quote[0048] Advantageously, during said step of bringing hydrogen into contact with said clusters, the hydrogen flows with a speed less than 3 m/s. Said hydrogen flows preferably according to a direction that is substantially parallel to the surface of said clusters. In such condition, the hits between the hydrogen molecules and the metal substrate occur according to small impact angles, which assist the adsorption on the surface of the clusters and prevents re-emission phenomena in the subsequent steps of H- ions formation.
Quote[0053] In particular, said step of triggering said nuclear reactions provides an impulsive triggering action selected from the group comprised of:
- a thermal shock, in particular caused by a flow of a gas, in particular of hydrogen, which has a predetermined temperature that is lower than the active core temperature; [...] -
Yes, there is some danger of catastrophic high temperature melting of the alumina - Zhang Hang has seen this with H2 present. These do not seem to be too explosive - which is a little surprising. My system minimizes the H2 dead volume in the system - there is less than 1mL in the whole system on the reactor side of the valve. That's why I use the small tubing. This tubing is available with 1/16" OD and 0.005" ID (tiny, capillary). The tubing is made primarily for gas chromatography systems.
The Rossi melt-downs in Italy and NC were not explosive events. A loud 'pop' is all you get. I think this is because while there might be high-energy events in a reactor, there is not the blast wave or high-speed shrapnel projection we normally associate with our idea of an explosion, since that is caused by large expanding volumes of gas produced by the rapid-phase-change of (say) TNT to gas.
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16:00 UTC graph update: round2-pdf-1491064933.pdf
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I'm sorry I was not clear. Use the image icon on the tool bar to alleviate the need to download and open a pdf. Provide the image directly.
Maybe I am missing a MIME type for the default action on how to handle pdfs. I just see a link, is this how you do also? or do you see the image generated directly?
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When I upload an attachment I usually also click on "insert into message" in order to be able to include the link exactly where I want, which is useful when editing comments over again to add a new updated pdf.
I too only see a link and not directly the pdf. When I click on the link a new browser tab opens with the pdf file displayed, or I could also right-click on the link to download it.
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can,
In the case of Piantelli and his rod-type experiments, he uses the thermal shock to trigger a thermal wave resonance. The thermal wave is a means that he uses to stimulate LENR on the surface of his rod, but it is not fundamental to LENR as a whole. This won't work on a pile of powder. Thermal waves are an obscure phenomenon - the velocity is slower than the speed of sound.
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What do you think about this? It hasn't to do with thermal wave resonance:
https://www.google.com/patents/EP2754156A2
Quote4. A method according to claim 3, wherein said step of ionizing said hydrogen (31) comprises the steps of:
- prearranging an electron-donor material (75) that comprises at least one electron-donor chemical element, proximate to said primary material (19);
- conveying and impacting said hydrogen (31) on said electron-donor material (75),
Quote5. A method according to claim 4, wherein said at least one electron-donor chemical element is selected from the group comprised of: Cesium, Barium, Strontium, Rubidium, Lithium, Sodium, Calcium, Potassium,
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can,
Piantelli believes that the H- anion, adsorbed onto the surface of the Ni is the fuel made available to the reaction. Here he has written a patent with a method to increase the reaction by supplying more H- anions. It is not required, because the Ni itself will catalyze splitting of H2 on its surface, but this might be a way to stimulated the reaction by making more available. Note that the mean free path of an H- anion at the pressures involved is not very far - a micron, so the alkali metal would have to be very close to be effective. In the case of Ni + LiAlH4, the liquid Li-Al-H metal completely coats the Ni. Li-Al-H is an ionic hydride and inside the liquid metal, the H exists as H-. So, in this case, the Li-Al-H coating is what is exposed to the H2, it breathes in some amount depending on the temperature and the amount of H already in solution, and converts all of the H2 into H- anion.
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17:00 UTC graph update; temperatures have been increased to 1150°C.
EDIT: 18:00 UTC update:
Even with this LiAlH0.x coating hypothesis, wouldn't providing an active flow of hydrogen diffusing through this layer allow the underlying Ni to be exposed to more H- per unit of time? Besides, how much breathing might be occurring during static conditions?
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can,
Sorry I had to take a nap.
The Parkhomov reaction has been shown to operate at low pressure, and not at higher pressure. How would having "fresh" H2 make a difference by circulation in the Li-Al-H takeup of H? It may prove desirable to have some stimulus, but circulating the H2 probably isn't it, just like having a tiny circulating fan is not going to make any differenc. Due to the light weight of the H2, the gas is already moving very fast inside due to thermal kinetic motion. Coming up there will be some changes in the power to the reactor during the TEST command. I am hoping these will serve as a stimulus. Pressure cycling would be another possible stimulus, but since I don't have a gas source connected, I cannot provide that in this experiment.
