Hydrogen from Iron

https://www.sciencedirect.com/science/article/pii/S2468067219300318

https://www.sciencedaily.com/releases/2019/11/191112142930.htm

I did a brief search for your proposed simple setup of using iron powder and water to make hydrogen gas. I could not find any references to this simple setup. As I should have expected, this did lead me into the HOH, perpetual machine fantasies. I did see the all iron battery presented earlier but something else caught my eye.

An iron powder combustion report published by the IEEE.

This seems like an excellent approach for energy capture. As usual the devil will be in the details, like net efficiencies, hazards, etc. but overall I like the approach.

Add a little aluminum to the mix and you have Thermite.

True but I think fused Thermite might not be as readily reversible.

..."Disposable chemical pads employ a one-time exothermic chemical reaction. One type, frequently used for hand warmers, is triggered by unwrapping an air-tight packet containing slightly moist iron powder and salt or catalysts which rusts over a period of hours after being exposed to oxygen in the air. Another type contains separate compartments within the pad; when the user squeezes the pad, a barrier ruptures and the compartments mix, producing heat such as the enthalpy change of solution of calcium chloride dissolving.

The most common reusable heat pads contain a supersaturated solution of sodium acetate in water. Crystallization is triggered by flexing a small flat disc of notched ferrous metal embedded in the liquid. Pressing the disc releases very tiny adhered crystals of sodium acetate^[1] into the solution which then act as nucleation sites for the crystallization of the sodium acetate into the hydrated salt (sodium acetate trihydrate, CH₃COONa·3H₂O). Because the liquid is supersaturated, this makes the solution crystallize suddenly, thereby releasing the energy of the crystal lattice. The use of the metal disc was invented in 1978.^[2]

The pad can be reused by placing it in boiling water for 10–15 minutes, which redissolves the sodium acetate trihydrate in the contained water and recreates a supersaturated solution. Once the pad has returned to room temperature it can be triggered again. Triggering the pad before it has reached room temperature results in the pad reaching a lower peak temperature, as compared to waiting until it had completely cooled."....

https://en.wikipedia.org/wiki/Heating_pad#Chemical

BUT:this was a multi use heat pad.Did not need to be heated.It simply required the addition of water.

It could have been as simple as lye,mixed with sand,and when it dried out,the reaction stopped.The canvas pouch was semi-permeable to water,and it would take about 5 minutes to absorb the water.The the bag had to be massaged for a couple of minutes to distribute the moisture.Then it would stay hot till it dried out;several hours.It felt like a bag of sand,weight and texture.

Cannot find it on any surplus sites.There may be some in the fallout shelters from the 50's and 60's somewhere.

IMHO:You are the Guru of net searches,so if you can't find it, probably no one can.

...."This is a US Army Medical Department LIGHTNINGPAK Heat Pad. One version is shown in the March 1944 MEDICAL SUPPLY CATALOG on plate 39. It has an OD Case marked with a caduceus and US. It measures 7 1/2" by 7 1/2". The top lifts up so you can insert the Heat Pack. The Heat Pack is is a khaki color and marked LIGHTNINGPAK and has directions all over it. On the bottom it is marked ROSE-DERRY COMPANY, Newton Mass. It has a patent number of 1,901913. These heat pads were issued to doctors and NCO corpsmen in the Aid Stations or Hospitals. "...

https://armysurpluswarehouse.com/heat-pad/

https://www.us-army-military-shop.de/Ausruestung/sonstiges/US-ARMY-HeizbeutelWaermebeutel::263.html

BINGO! You found it!

I searched diligently but in vain for it.

Thanks a million!

Any way to find out the ingredients?

The second link is the one I am referring to.

The first link is a hand warmer,with very limited cycle life.

Now I will try to find a supplier in the USA for it.

https://patents.google.com/patent/US20100136186A1/en

Interesting that you can use hydrogen to reduce the iron oxide, removing the pain of transporting and storing hydrogen, especially if you can reduce the iron oxide without having to expend the energy to "re-powder" the iron.

It doesn't look too good for transportation fuel. The amount of energy per liter is better than gasoline, but energy per kg is only 1/10 of gasoline.

I agree, we have to look at the overall efficiency.

https://spectrum.ieee.org/energywise/energy/renewables/iron-powder-passes-first-industrial-test-as-renewable-co2free-fuel

I don't see where hydrogen has anything to do with this. The iron simply burns on its own when exposed to oxygen. The slow version is called rusting. The fast version, facilitated by small cross-section of the iron, is simply normal combustion.

"Progress of hydrogen gas generation by reaction between iron and steel powder and carbonate water in the temperature range near room temperature"

https://www.sciencedirect.com/science/article/abs/pii/S0360319920310247?via%3Dihub

I don’t believe it’s from the iron itself. On the physical metallurgy aspect in a welding process, there is a problem called hydrogen cracking, where as you’re welding, hydrogen is created from moisture, humidity, grease, oil, etc... where the weld would fail.

my point is, hydrogen is for a lack of a better word, derived from a process, but I doubt if it’ll be feasible on a production scale. Or instead of derived, ‘mined’ might be a better term.

For info - low hydrogen welding rods have been around since Methuselah's tom-cat was a kitten and a submerged arc solves the bulk of the problem, as do angle grinders and good old fashioned heating, anyway

The point I was making was about the process, not the mitigation of.

As stated for info-knowledge about it existed but not the uses

I was involved in an experiment where steam was passed through red hot iron turnings to produce H2 and rusty iron or iron oxide. The process did produce H2 and it could be tested and showed a way to make H2. The iron in water works to produce H2 but is a slow process which was sped up by using steam and hot iron.

However considering that in the beginning the iron was extracted from the iron oxide ore by removing the oxygen from the ore with coke and producing CO2, we then get into the area of carbon footprint and anyway the iron turnings can be better used as a feedstock back into the steel making.

Seems as if it is a high energy consumer to make H2. First to turn iron oxide to iron and carbon dioxide, then to heat water and the iron to get back to iron oxide and hydrogen.

<...water...>?

It would be easier to use vinegar.

...or lemon juice.