Tried with lead electrodes, 500 mL tap water and some NaOH to get about 15V, 0.7A, 11W.
No Carbon in the tank I take it? We have avoided strong bases btw, best results with carbonates - sodium or potassium - or even sodium bicarbonate, so not sure what might be happening in your tank. Sounds like pxidation/plating though. Tap water is fine btw.
For the catalytic nature, any idea of the turn-over number? Units of g carbon/g aluminium consumed or g H2 produced would be helpful.
For the catalytic nature, any idea of the turn-over number? Units of g carbon/g aluminium consumed or g H2 produced would be helpful.
DAK. There's no point in me posting stuff if you don't read it.
Since the reaction looks like this 2Al + 6H2O = 2Al(OH)3 +3H2 you can see that 60 grams of Al give you 6 grams of hydrogen, and as a by product just over 160 grams of hydroxide. If we up the scale a little, you can see that 1 tonne of aluminum scrap costing $850 would yield 100kgs of H2,and something like 2.5 tonnes of smutty hydroxide worth at least $250 to a smelter. So the hydrogen element costs around $6/kg in material costs- which is stinking cheap!
I am not familiar with the expression 'turnover number', but as it is essentially catalytic the carbon is not consumed. In fact, if you use 5-micron carbon black to make the CC a 1% by weight suspension in water will go on producing hydrogen for as long as you want to feed it aluminium and water. One of the group has kept such a system going intermittently for more than a year. As it's a catalyst btw, surface area helps, but it is so cheap and easy to make, and required in such modest amounts that we have never worried about measuring any losses, but have checked for loss of activity over time. That has not been seen yet, batches of CC prepared up to 3 years ago and left to dry out still work very well.
No Carbon in the tank I take it? We have avoided strong bases btw, best results with carbonates - sodium or potassium - or even sodium bicarbonate, so not sure what might be happening in your tank. Sounds like pxidation/plating though. Tap water is fine btw.
No carbon. Tried to simplify it, but got nothing. So carbon may be necessary, or some other stuff.
I did read you post. Turnover number is a measure of the effectiveness of the catalyst which reflects in the cost of the whole operation. It is a common metric for an industrial process. In your case you can express it as either grams of hydrogen/grams of carbon or grams of aluminium used/gram of carbon. Hydrogen would be easier to work with.
There is no catalyst that I know of where the turn-over number is infinite. However, I should temper that with the statement that I am not a catalyst expert. I guess in your case, the amount of carbon affects the rate of hydrogen production. You can test if the catalyst degrades by measuring the rate of production vs. time assuming that aluminum is in vast excess over the carbon. You also need a blank.
I guess in your case you are aiming for hydrogen production and not the by-product of alumina. At $6/kg that is not cheap. The cost of hydrogen is tied to the cost of natural gas. At the 2012 prices it was retailing for about $3.50/kg. Now is it under $1.50/kg.
You can of course make it from any carbon source and water. Those are not industrial prices so you factor in a lot of extra costs.
A crap-grade (99%) cylinder costs somewhere at $20 (I forget as I buy it so infrequently and the cost is low enough to ignore) and contains about 700g of H2 but these are not industrial prices and includes delivery of single cylinders. Thus, I believe the above estimates are reasonable. If you have other figures, let me know.
A crap-grade (99%) cylinder costs somewhere at $20 (I forget as I buy it so infrequently and the cost is low enough to ignore) and contains about 700g of H2 but these are not industrial prices and includes delivery of single cylinders. Thus, I believe the above estimates are reasonable. If you have other figures, let me know.
I have no other figures and have no argument with your price estimate. But Hydrogen at the price you mention is because all around you are $Bn's of infrastructure that make it possible. The plant than makes the gas, and the other plant that makes the bottles, the highway network and cut-throat competition in the delivery chain. Try to get a bottle of Hydrogen in the other 2/3 of the world that has little or no equivalent infrastructure and things might be different.
The idea behind CC is that it can be truly 'Hydrogen on Demand' made by recycling scrap Al and using charcoal as a carbon source. Water can be almost any kind, electrolytes can be harmless carbonates. Catalyst is so cheap that it's cost is negligible and AFAIK we don't know the turnover number except to say 'it would be very good'.
Incidentally, getting a 'Hydrogen Storage Permit' in the EU is almost impossible unless you feel confident that your location will pass a very stringent fire department inspection. Anything within quite a few meters of a dwelling of any kind is ruled out immediately. It's a bit mad, and probably a hang-over from the Hindenburg/R101 disasters because acetylene, butane and propane are freely available. Hydrogen isn't. 
We have the similar requirements but it is for liquid hydrogen. As to flammable gases, methane tends to be the bad actor in the US but we do not have many people using bottled hydrogen vs. propane or natural gas. Hydrogen is actually quite safe but a similar LEL to methane. The Hindenburg caught fire due to its flammable covering (at least that is the story I remember). The hydrogen certainly helped fuel the fire but was not the initial cause. That disaster was in the US in any case - NJ.
Enough for now on this subject. I still think you could build a small electrolysis system for <$100 and it would be or interest to the LENR community if properly engineered and with a gas purifier present. Safety approval may be a challenge and thus likely double (or more) the cost.
Anything within quite a few meters of a dwelling of any kind is ruled out immediately. It's a bit mad, and probably a hang-over from the Hindenburg/R101 disasters because acetylene, butane and propane are freely available. Hydrogen isn't.
That is probably for good reason. See the book "Tomorrow's Energy" by P. Hoffman. It is gung ho in favor of hydrogen, but it describes some serious problems. You cannot see hydrogen when it burns, and it leaks more easily than other gases. At Osaka U. a high tech hydrogen fueling station exploded a few years ago, and several others have done that. Hydrogen fueled cars have exploded. Hydrogen is used industrially in Germany. They have had a 130-mile pipeline which was started in the 1930s (p. 205). It is very safe, but I have the impression it is tricky and it is safe because they have a lot of experience.
Hydrogen generated locally, stored and then used to generate electricity might be a good way to store wind energy. It might be better than batteries. Sending it elsewhere through pipelines would be problematic. The pipes would all have to have new inside lining. Natural gas pipes would leak. That is a shame, because wind energy in the U.S. could be used to make gas or liquid fuel, about 5 to 10 times more energy than the U.S. consumes. They could make more fuel than all of the oil wells in the Middle East, putting OPEC out of business. The problem is, the easiest synthetic fuel would be hydrogen but there is no infrastructure to deal with it.
I still think you could build a small electrolysis system for <$100 and it would be or interest to the LENR community if properly engineered and with a gas purifier present. Safety approval may be a challenge and thus likely double (or more) the cost.
More like $10,000. I have seen hydrogen purification systems that produce laboratory grade hydrogen. One was made by Mizuno and his grad students at U. Hokkaido for research unrelated to cold fusion. The other was at TAMU, as I recall. These things are complicated. If you just want low grade impure hydrogen you might make one for $100 but I would bet you blow yourself up with it. I wouldn't want to go into the building where you keep it.
It depends on the volume of H2 produced and the service requirements for hobbyists vs. industrial applications. I was thinking of 1-10 mL/min. A number so low that there is no safety issues. Remember the LEL for H2 is about 5%. The real issue is all the regulatory requirements to sell anything in the US.
also
the SHT generator
http://www.e-catworld.com/2015…-trends-publishes-patent/
MULTIFACTORIAL HYDROGEN REACTOR Inventors: BALAKIRYAN, Konstantin (US) AGANYAN, Hakop (US) Publication Date: 15.01.2015 Pub. No.: WO/2015/005921 International Application No.: PCT/US2013/050031
Abstract: The present invention provides multifactorial hydrogen reactor with elevated hydrogen production due to complex set of sixteen (16) physical and chemical processes, acting simultaneously on the hydrogen bonds in aqueous solutions of electrolytes. This is achieved due to the process, which takes place in forty two (42) distributed volumes of hydrogen reactor under the effect of the electro-hydraulic shock, which forms local micro-cavities with pressures in the hundreds of thousands of atmospheres and a temperature of several thousand degrees (plasma). Frontline water wave pressure passing through electrolyzer's electrodes creates in micro-environment infrasonic, sonic, and ultrasonic vibrations that, along with the heat, ultrasound and hydrodynamic cavitation, turbulence, high-pressure, chemical catalysts, light energy, electrostatic and electromagnetic fields, dramatically increases decomposition process of water molecules. Simultaneously, electro-hydraulic shock destroys the oxide film, allowing the oxidation reaction of reactive metals to continue continually reactive metals, from which plates of electrolyzer are made, are part of the hydrogen reactor.
Sounds pretty good! What's the problem?
Edit. Aha, I see.
Pffft. I didn't get that far...
But anyway, it still sounds like a cool hydrogen generator. They were probably just winding up Sterling Allan.
SHT generator...
That's the way a chemist would do it!
Sieves - done all the time. Generally to make dry air free of CO2. Doesn't generate hydrogen nor purify as well as a Pd/Ag membrane. Simple absorbents such as Drierite + Fe (basic pyrogallol is the classic method) would work reasonably to remove water and oxygen on limited volumes.
How far are those 10cm*10cm lead electrodes from each other? Just thinking about resistivity of the electrolyte in the reactor.
