What about the current Geiger counters readings seem a bit high! 13.36 Move upwards!
The Geiger counter readings are consistently in the range of 40-50 CPM, with some diurnal variation. No short-term events like the neutron ones have been seen. The cell body of 2.5 mm thick stainless steel would block charged particles and most (>90%) photons below 100 kEv.
MR4.3 Update
During 24 hours at 200 watts, the cell still matched calibration temp (292°C) within ±1 degree. The pressure rose substantially during this interval, rising from 450 to over 1100 Pa. The rate of pressure rise appears to be tapering off rather than linear.
RGA analysis shows a wide range of masses, in clusters around the main fractions seen previously: Hydrogen at mass 2, 3 and 4; Oxygen and water at mass 16, 17, 18; Nitrogen at 28; and CO2 at 44. Understanding this complex gas composition will need help from someone skilled in the art of RGA analysis, but the presence of so much CO2 seems to indicate continued out-gassing rather than leakage as the primary mechanism involved.
To further test the source of rising pressure, the cell will be left at 200 watts for another day. The rate of pressure rise should continue to taper off confirming lack of air leakage into the cell. The live stream is still running after 6 days at https://www.youtube.com/watch?v=6NXCxsrwHOE
The question is where the Oxygen is coming from - CaC02?
The question is where the Oxygen is coming from - CaC02?
Thermal decomposition of CaCO3 (limestone) to CaO (quicklime) + CO2 is one of the oldest and most widely used chemical reactions in human civilization. In this case, it's probably helped by the catalytic properties of Ni and Pd, since lime kilns usually run at 900°C. The oxygen is probably stripped from metal oxides by hydrogen reduction.
MR4.3 Denouement
This test used two sheets of Ni mesh prepared with Pd according to the recipe of Rothwell and Mizuno. During six days of testing at up to 300°C, no excess heat or unusual radiation was seen. Substantial out-gassing of Carbon Dioxide and Hydrogen were observed when the cell temperature exceeded 200°C. Live video showing the data and thermal camera image was streamed to YouTube covering the entire duration of the test, but the video is unfortunately not available after the live stream ended. Post analysis and more details of the experiment can be found at https://tinyurl.com/vudbmro.
The complete .csv data files are available at https://tinyurl.com/y28dysc4
Great job, Alan. I very much appreciate the work you are doing. Very thorough and very open.
What is the next step with your apparatus?
Again, thanks for the persistence and the sharing.
What is the next step with your apparatus?
No definite plans yet, since there are some questions raised by the latest results that need analysis and discussion. One concern in particular is the wide temperature profile shown by the thermal camera display. The external heater coil is wound around the cell with uniform turn spacing. So the middle gets hottest, and the ends coolest. The rolled meshes are the entire internal length of the cell (250 mm), so they see a similar temperature profile.
A significant finding of this series of tests is that the core (thermowell) temperature matches the external temperature within a few degrees once equilibrium is reached. The rolled meshes are the entire internal length of the cell (250 mm), so they see a similar temperature profile to the exterior, aided by the high thermal conductivity of the deuterium gas in the cell.
As a consequence of this, if there is a critical temperature for certain things to happen (loading, crack formation etc.) it will only be seen by a small area of the mesh at any heater power. For example, there was a possible increase of neutron detection following about 10 minutes after each of several power bumps. That might result from a critical reaction temperature moving to a new area of mesh.
So one possible next step is to wind the heater coil on my second reactor in such a way as to cause a more uniform temperature profile along the tube. I envision the equivalent of how a Helmholtz coil creates a uniform magnetic field. There's no easy math for the thermodynamics of the physical cell, so trial-and-error, fine tuning, new calibrations, then more tests. This would mean a commitment to many months of work on my part, not to be made lightly.
thank you very much for your willingness to share
We're all starved for entertainment these days, and this site is more interesting than the usual reruns and sitcoms (other than The Expanse, which continues to amaze me).
But it's serious work and essential mental exercise more than just entertainment. So getting back on topic, I need some help understanding the
RGA plot shown in #2925 above. I suspect you spent a bit of time looking at such things earlier in your career, so please share any thoughts in that regard.
Most steel contains carbon. But what is the source of oxygen?? Leak?
Can you calculate the absolute mass of the components based on volume moved to mass spec?
Wyttenbach My answer when you asked the same thing yesterday remains: the CO2 comes from dissociation of CaCO3 deposits on the mesh. That in turn results from the last step in the mesh preparation recipe - a 1-hour soak in domestic tap water at 90°C. My local water, like Mizuno's has about 50 ppm of CaCO3, and that increases during the hot soak from evaporation of the water bath. I have SEM/EDX images that show the presence of Ca over the entire mesh surface after that treatment, and will post those when time permits.
The oxygen probably comes from reduction of surface oxide on the Ni mesh, which has been stored in air for two years or more. The rise in water and other hydroxyl ions is evidence of that process.
I have had plenty of experience hydrogenating nickel powder of various types, ranging in size fron 2.5 to 50 microns. Normally this was done at temperatures up to 300C and using 5 cycles of vacuum, hydrogen admission (atmospheric pressure) and heating and then unforced cooling. Generally the first 3 cycles would produce visible condensed water vapour. As both the hydrogen and the vacuum equipment was very carefully dried, so it would seem the most likely source for the condensate was the reaction product of surface oxides and adsorbed free oxygen on the nickel. This was pretty much confirmed by the absence of condensate by the final cycle.
Alan Smith Thanks. The current run (4.3) was preceded by two cycles of bake-out, then two prior experiment runs (4.1 and 4.2) with added hydrogen (Deuterium). Your experience suggests that several more cycles may be needed to remove remaining traces of oxides and adsorbed gases and water. That's easy enough to do, and can be monitored from anywhere that has internet access.
So the short answer to Nick's question above is, more of the same: pump out, cool down, add Deuterium, add heat and see what happens. Up next MR4.4
Your experience suggests that several more cycles may be needed to remove remaining traces of oxides and adsorbed gases and water.
Some Japanese Researchers said bake-out can last 3-4 weeks! Of course with different phases like removing oxides (if needed) out gazing Hydrogen/carbon, nitrogen etc... Must be quite boring and needs good planning!
Wyttenbach I was aware of that, and did several cycles of bake-out followed by several cycles of oxide reduction (MR4.1 and 4.2) prior to this run.
I found at the start of this project that the "official" recipe presented by Rothwell resulted in deposition of Calcium Carbonate on the Ni mesh, and that is unique to the Mizuno recipe as far as I know. It results from using tap water, concentrated by evaporation of the open bath, and leads to the generation of copious Carbon Dioxide when heated above 250°C. Conventional lab practice would be to use deionized water in a closed container, and to give some reason or goal for the treatment. I found this departure from normal practice to be curious from the beginning, and asked about it several times but received no further clarification.
that is unique to the Mizuno recipe as far as I know.
No! Takahashi does calcination since at least 2 years. He also reports that they must redo this step after some time. Key is to get excess heat far below the decomposition point of CaCO3. The other point Ca should be close to Pd!
But the whole receipt for me looks like a creative fantasy. If CaCO3 is needed, then you have only one chance to ramp up the reaction. Without knowing how to do this step you walk in a desert.
Wyttenbach : calcination has nothing to do with CaCO3. Those 2 are complete different things
Palladium on CaCO3 is known as a Lindlar Catalyst. It's widely used for hydrogenation in synthesis of organics such as Vitamin A. In such applications a "catalyst poison" is added to reduce the hydrogenation to a single bond. What I see in my prepared mesh is a very crude form of such a catalyst, where the Calcite is mixed into the deposited Pd by the burnishing process. Details of this structure can be seen in the image below, from my paper from August 2019.
I have changed the 120 V lamps (in the bank of four) inside the calorimeter.
They are as follows from left to right: 75 W Sylvania Black Light, 200 W Sylvania, 150 W Sylvania, and one of the original 25 W Sylvania lamps from previous (in the same position). This gives many input power configurations, currently in mid test.
The tests will proceed with the following increments: 75 W, 150 W, 200 W, 250 W (75+25+150), 300 W (75+25+200), 350 W (150+200), 375 W (25+150+200), 425 W (150+200+75), and 450 W (75+25+150+200), each for at least two hours, sequentially.
Currently, the 300 W step is running.
Also, the earlier 100 W lamp used is not made by Sylvania as previously noted. It is a generic, bulb probably Chinese in origin, and I suspect it is actually rated at 130V although it is marked 120 V.
The Sylvania lamps seem to be performing very close to the rated power, (likely almost exactly if normalized to 120 V from the actual experiment voltages) so that brand is currently being used exclusively where possible.
I also have acquired a 1200 W, adjustable 0-120 V DC power supply with current and voltage limiting. I need to change the current and voltage datalogger setup before it can be tested above 5 A or 70 V, so that will have to wait for a bit.
Palladium on CaCO3 is known as a Lindlar Catalyst. It's widely used for hydrogenation in synthesis of organics such as Vitamin A. In such applications a "catalyst poison" is added to reduce the hydrogenation to a single bond. What I see in my prepared mesh is a very crude form of such a catalyst, where the Calcite is mixed into the deposited Pd by the burnishing process. Details of this structure can be seen in the image below, from my paper from August 2019.
I have seen platinum and palladium with native silver and gold naturally occurring in carbonate (mostly calcite) veins, associated with selenium.
That’s all I am saying about that other than it is true.
