The original clamshell design used an inexpensive stainless steel reactor tube that would directly seal with a 1/4" Swagelok and the tubes only cost $3.60 each. The problem I discovered was that the stainless could not withstand 1200C for any time - they would corrode through even with no fuel. The stainless steel tube can still be used for temperatures up to about 800C, and can still be used in this apparatus. To deal with the temperature, I switched back to an alumina reactor tube. But, doing that you have to face the ceramic to metal seal issue. The "heatsink" is the round aluminum 1/2" thick disk that the tube passes through. This is part heatsink and part centering mount for the tube end. The heatsinking is needed to keep the seal as cool as possible because of the ceramic-to-metal seals. Generally, ceramics have a thermal expansion coefficient about 10x less than metals, so you want to limit the temperature change at the seal.
MFMP: Automated experiment with Ni-LiAlH
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I take that the powder is in contact with the ceramic tube. Won't the lithium/lithium compounds in LiAlH4 react with the Al2O3? If it doesn't right away, it should eventually as temperatures are increased and the lithium volatilizes. I'm not saying that it's an undesired thing, only wondering if you recognize that it will happen.
For disclosure: my hypothesis is that various alkali-metal oxide phases have to form, but alumina may not necessarily work.
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Won't the lithium/lithium compounds in LiAlH4 react with the Al2O3?
I have run over 60 fuel mix tests using on occasions as much as 20% LiAlH4, LiH, Li chips in various proportions at temperatures of 800C+ for up to 4 hours in one session, and sometimes reheated them for further periods. The fuel load is always around 1 gm, and the tubes are 99% Alumina + 1% various metal oxides, with an average wall thickness of 0.7 mm. Never ever had a melt-through caused by lithium corrosion. I'm not saying it's impossible, but I have never seen it happen.
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With 800°C are you referring to an internal or external temperature?
EDIT: several sources are reporting the unsuitability of alumina to exposure to lithium metal and lithium metal compounds at even relatively mild temperatures, but I guess it's plausible that the reaction probably also depends on its purity and manufacturing quality. The following papers are a bit dated.
http://www.sciencedirect.com/s…icle/pii/0022311585904544
https://www.osti.gov/scitech/servlets/purl/4330702
http://www.iaea.org/inis/colle…Public/09/410/9410560.pdf
https://ntrl.ntis.gov/NTRL/das…tleDetail/UCRL50647.xhtml
Pages 21-22
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800C external...in the reactor ports.
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Have you ever tried using Lithium only (or Lithium and hydrogen) in one of your ceramic tubes to check for any sign of reaction at high temperature? I'm wondering if your tubes are particularly unreactive or if somehow it's the combination of internal conditions which prevents the lithium from reacting (significantly, at least).
Some users who attempted a replication in the past, like jeff (Nov 2015), have seen a reaction of Li with the ceramic tube:
jeff: E-Cat Replication Attempt (photo attached in the linked comment as a pdf file)
Clearly alumina does not work as a containment material when molten Li is present. See the attached photo. Based on a URL that I posted earlier today, the results were not unexpected. I'm just amazed by how reactive molten Li really is. I'll need to line the cell with a metal that is compatible. The previously mentioned article suggests pure Fe, ferritic stainless or Mo, Ta, W. Ferritic stainless is probably the easiest to get.
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There is some literature about corrosion due to high temperature containment of molten Li that comes from the hot fusion field. You hear them talk of "lithium blankets" for the reactor. So that is the reason for the materials research. Pure Fe (really hard to get today for lack of market) is one of the best materials. For the single run experiments I run with 99+% alumina, there should be no problem for a few weeks.
The use is stainless steel inside probably works OK because it is bathed inside and out in H2. Oxygen at high temperature is the bigger problem with stainless. I have also seen that a Ni foil canister works well inside as a fuel container bathed in H2 - this also serves to prevent contamination of the fuel that could confuse post-reaction metallurgical analysis.
I have seen results from an experiment where the alumina (of unknown quality) actually had a melt bubble form and burst. Funny thing, it was not over the bulk of the fuel, but at the edge. It appears that right at that edge alumina wool (high in silicates and metal oxides) was present as a plug for retaining the powder. It appears that the melted Li-Al wicked into the alumina wool and chemically reacted in a thermite-like oxygen exchange reaction that caused the temperature to rise quickly at that point and melt the alumina tube. I use a small plug about 0.1" thick of zirconia felt with a loose alumina rod to keep it in place. This will be the first time to try that. We'll see how it works.
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[...] For the single run experiments I run with 99+% alumina, there should be no problem for a few weeks.
The use is stainless steel inside probably works OK because it is bathed inside and out in H2. Oxygen at high temperature is the bigger problem with stainless. I have also seen that a Ni foil canister works well inside as a fuel container bathed in H2 - this also serves to prevent contamination of the fuel that could confuse post-reaction metallurgical analysis.
Sorry, but I don't quite understand from this if in the upcoming experiment you're going to let the Ni-LiAlH4 powder be direct in contact with the ceramic tube or if you're gong to use some kind of metallic foil or canister to prevent it.
I have seen results from an experiment where the alumina (of unknown quality) actually had a melt bubble form and burst. Funny thing, it was not over the bulk of the fuel, but at the edge. It appears that right at that edge alumina wool (high in silicates and metal oxides) was present as a plug for retaining the powder. It appears that the melted Li-Al wicked into the alumina wool and chemically reacted in a thermite-like oxygen exchange reaction that caused the temperature to rise quickly at that point and melt the alumina tube. I use a small plug about 0.1" thick of zirconia felt with a loose alumina rod to keep it in place. This will be the first time to try that. We'll see how it works.
That sounds like an interesting reaction going on, worth investigating more in detail; who knows if there wasn't actually more than a simple chemical reaction, given the reaction environment. It's worth noting that in his first experiments that kickstarted the worldwide Lugano replication efforts, Parkhomov didn't use pure alumina tubes, and he didn't even use a vacuum pump to remove adsorbed gases and the initial atmosphere. His Ni powder was probably partially oxidized as well.
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Here are some photos of Glowstick reactor tubes after exposure to molten Li for a week or more. tubes made of Mullite show considerable degradation, probably due to leaching of the ~30% silica from the ceramic (first image). The tubes made of high purity Al2O3 showed no penetration or degradation from the contents (second image).
Regarding BobH's comment about Ni foil, I saw considerable degradation of a Ni foil fuel capsule in GS4 (third image).
https://drive.google.com/open?…xJkjesxe4kRzdHaGlOeDdQems
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These are good data points, Alan, and add to the science of what we are doing.
I would like to mention why mullite was used - it was because we believed that Parkhomov used mullite and we wanted to reproduce what Parkhomov did using nearly the same materials. At that time, Parkhomov had not started using the stainless steel canister for his fuel. Afterwards, it became clear that the reaction did not depend upon the mullite substrate. We all knew that high alumina would be a better choice for durability but we were unsure at the time whether the mullite's silicates were participating in Parkhomov's reaction.
I believe the use of containers for the fuel was initially begun to try to keep the reactor tubes from being single use devices by providing a means to remove the fuel without damaging the apparatus. Of course, re-use also meant that the container had to protect the tube. It hasn't seemed to work out well for those purposes because the fuel containers usually leak, and getting the reactor tube clear again usually damages the tube. I have planned instead to use the reactor tubes only once. The tubes will be dissected at the end to extract the fuel.
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We know from several years of attempts that lithium is corrosive and presents difficulties that must be worked around when building a garage apparatus. Is there any basis other than Lugano and Parkhomov for continuing to use lithium? It is true that hydrogen and nickel by themselves have not shown results, but there are many other possibilities beyond NiH and Ni/H/Li that have not been explored here but still fall within the broad category of nickel-hydrogen systems. For example, there are the "Polonium, Thorium, Uranium, Plutonium, Americium and a transuranic metal in general, or a combination thereof" mentioned in one of Piantelli's patent applications.
Could it be that lithium is making things unnecessarily difficult?
ETA: I note that lithium is mentioned in the Piantelli patent application, and it also makes an appearance in the Unified Gravity patent application (arguably unrelated to the kind of apparatus we're discussing here). So this is not to say that there's no basis for exploring lithium. But it also does not appear to be a critical ingredient, and there may be others that are easier to work with.
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Interesting photos. It looks as if in picture #2 lithium reacted with the internal surface, forming a sort of passivating layer preventing further Al2O3 from reacting. I guess that modern high purity alumina must be denser and tougher than what was commonly used a few decades ago as shown in the papers I previously linked.
But I think I'm being misunderstood here so let me clarify: what I'm ultimately saying is not that the exothermic reaction of lithium with the ceramic tube is responsible for the observed excess heat, but rather that Parkhomov didn't seem to care too much about having a clean, oxide-free environment for the reaction (almost the opposite, actually). These oxides would for the most part react with the lithium in the LiAlH4, forming not easily reducible complex alkali/alkali-metal oxides.
The possibility that the fuel in its active form is composed of mixed metal/alkali metal-oxides has not been thoroughly explored yet in these replications. -
But I think I'm being misunderstood here so let me clarify: what I'm ultimately saying is not that the exothermic reaction of lithium with the ceramic tube is responsible for the observed excess heat, but rather that Parkhomov didn't seem to care too much about having a clean, oxide-free environment for the reaction (almost the opposite, actually). These oxides would for the most part react with the lithium in the LiAlH4, forming not easily reducible complex alkali/alkali-metal oxides.
A couple of points about Parkhomov. He did almost certainly use a S/Steel fuel capsule inside his reactors -certainly by the time of ICCF-19 where he showed me one. Also, it has since been discovered that he does do some (unknown) degree of fuel preparation.
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A couple of points about Parkhomov. He did almost certainly use a S/Steel fuel capsule inside his reactors -certainly by the time of ICCF-19 where he showed me one. Also, it has since been discovered that he does do some (unknown) degree of fuel preparation.
I'm aware too that he did later on start using stainless steel capsules (I think the intention was initially to make the powder easier to extract). If the powder was prepared to obtain what I believe could possibly have more chances of working (= metal/alkali-metal oxides), that would not be important however.
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Well, what you said is not quite true. Piantelli's early results were with pure Ni and isotopically natural H2. He only used a Li shell later as an afterburner to get more heat out of his emitted high energy protons, but even this was not in his initial experiments that showed XH. Mizuno's low pressure plasma experiment was the same - pure Ni wire and isotopically natural H2.
We have seen a lot of no-XH-found experiments from garage shop experimenters who used just plain Ni. I have a working hypothesis under evaluation for why Ni-H LENR has not been reproducible.
There is nothing that says that Li is a magic ingredient, but it has been present in many successful experiments (including Pd-D). Most importantly it was part of Parkhomov's successful experiments where he fully reported his fuel. Once you have a setup that allows you to try lots of fuel mixtures, evaluation of other ingredients seems reasonable. However, putting together an apparatus for controlled experimentation is not easy or cheap. If adequate controls are not placed on the experiments, then alternate fuel evaluations would be very frustrating. One way to evaluate multiple fuels is to do something like what Alan did where there is more that just one control location. For example, suppose you had a Glowstick with 5 sections, 2 of which are controls, and the other 3 are for evaluating fuels. You could just look for the one that is the hottest (and it better not be a control). This provides a quick means for evaluating multiple fuel compositions in the same approximate conditions. Looking for one that is the hottest (all in the same tube, absolute numbers not important) could be done with a thermal camera.
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Yes, Parkhomov's early work and the Lugano test both seemed to suggest that in-situ fuel processing (vacuum, H2, etc) may not have been necessary if the starting ingredients are properly prepared. The molten Al is a very strong oxide getter and will soak up and lock up O2 inside the reactor as Al2O3, one of the most stable oxides. The fact that the early Parkhomov and Lugano experiments were done with no in-situ processing suggests that there is a valuable trick to be found in the fuel pre-treatment. If my hypothesis for what this treatment comprises and why it is valuable proves useful, I will write-up my entire thinking about it for everyone else to try. If I were to just explain my thinking now, aside from all of the possible meals of crow I would have to eat, it may send other researchers in the wrong direction. Even if I cannot verify it, I will still say what I believe is important after I have had some soak time with it and have gathered the evidence for my case.
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[...] If I were to just explain my thinking now, aside from all of the possible meals of crow I would have to eat, it may send other researchers in the wrong direction. Even if I cannot verify it, I will still say what I believe is important after I have had some soak time with it and have gathered the evidence for my case.
How is discussing the idea in an internet forum with the appropriate disclaimers going to send other researchers in wrong directions?
I'll tell you mine, which is very simple: there's at least one case in the mainstream scientific literature where the fuel, or better the active component which produces the fuel, is a commonly employed alkali-metal oxide mixture. The theory of operation does not focus on that specific mixture, it's more or less general to catalytic alkali/metal-oxide systems; there's therefore a strong suggestion that it might be also applied to relatively "dirty", Parkhomov-like Nickel-Lithium systems. By now you've probably already guessed what I'm talking about.
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Keep in mind that both the Glowstick and Parkhomov reactors used LiAlH4 in the fuel, rather than pure metallic Li. Thus the molten metal present was LiAl, not pure Li.
In GS5.2, about 100 mg of Nanoshel passivated Li was used in addition to the LAH, and that experiment produced the most interesting results to date. The attached image may show the effect of even such a minute amount of pure metallic Li in the fuel. This was after several weeks of elevated temperature cycling, up to 1300°C in the core. The effect on the 316L stainless steel capsule was also clearly severe.
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Keep in mind that both the Glowstick and Parkhomov reactors used LiAlH4 in the fuel, rather than pure metallic Li. Thus the molten metal present was LiAl, not pure Li.
That does makes sense.
But I thought of this. The second step of LiAlH4 decomposition is according to Wikipedia the following:
2 Li3AlH6 → 6 LiH + 2 Al + 3 H2
If the so-formed 2 Al readily react with available oxides (as the reaction occurs in a non-ideal environment), wouldn't this make for a larger Li fraction than a 50% mixture of Li and Al?
In GS5.2, about 100 mg of Nanoshel passivated Li was used in addition to the LAH, and that experiment produced the most interesting results to date. The attached image may show the effect of even such a minute amount of pure metallic Li in the fuel. This was after several weeks of elevated temperature cycling, up to 1300°C in the core. The effect on the 316L stainless steel capsule was also clearly severe.
It looks like the Li (and/or other metals?) diffused almost all the way through the tube thickness.
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can I'm not convinced the Wiki article correctly describes the decomposition. I think other references show at least one alternate path involving formation of LiAl*Hx as an ionic solution. This may be a distraction from the thread (Bob's current project), and crowd thinking seems pointed towards plasma right now. But it's still worth remembering what we discussed and did in 2016.
We've discussed the properties of LiAl several times in the past, particularly its curious quasi-ionic structure. Here's an excerpt of an interesting paper I just found that notes its lower reactivity compared to Li, and describes other unusual properties of this alloy.
