# Hydrogen



## Palladium (Feb 5, 2010)

I've been studying and playing with some hydrogen generator techniques using aluminum, water, and sodium hydroxide to create hydrogen on demand. Yep, i want to make me a hydrogen torch setup. Good old Aflac ingenuity. The problem is how to control the reaction rate. Water cooling and a few other techniques work. But i just wonder, hummmmm ?

Is their way to control the oxidation rate which occurs at the aluminum surface with electricity? It's like a cathode and anode. Except the sodium hydroxide is doing the oxidizing instead of the electricity. I don't need to speed the reaction up i need to slow it down by slowing down the amount of oxidation at the surface. This shouldn't consume electrons just balance them in the system. The electron action is between the aluminum and the sodium hydroxide. Anybody following this logic ?


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## butcher (Feb 5, 2010)

An Idea, cut up harddrive disk. I use old tile/paper shear,
in luted vessle one exit gas port for hose, one port for dripping in liquid as needed, (can have weighted cap lid For safty)

drip used acid peroxide or HCl, on aluminum as gas needed.

hydroxide solution could also be used.

in cell
current would play a roll in how much is produced in a cell, it can be regulated easily, also adjusting surface area may help (or distance )
raising and lowering in solution, concentration of electrolyte but that would be a bit harder to adjust, remember always use direct current for hydrogen, alternating current can get explosively dangerous.


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## Irons (Feb 5, 2010)

Let the pressure control the level of the NaOH, preventing a runaway reaction. Increasing pressure would expose less Al to the NaOH solution.


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## Platdigger (Feb 5, 2010)

I found an old patent, long ago, were the guy was generating hydrogen electrically, but it was more like a wire feed welder feeding aluminum wire to a rotating drum under water.

Aluminum oxide was formed and hydrogen released from the water. He had a motorcycle running on it.


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## peter i (Feb 8, 2010)

My experience making hydrogen from aluminum and hydroxide is, that it is a bitch to control. The speed of reaction is highly dependent on temperature ..... and generates quite a bit of heat. (yes, that is the standard recipe for runaway-reactions)That's OK if you just "want some hydrogen", but the moment you want a controlled reaction (in my case for filling experimental balloons) it is far too hard to control. 
I wasted a lot of time on it, before going back to using zinc and 30% hydrochloric acid (far nicer to work with). But only until the moment bottles of compressed hydrogen became available.
:mrgreen: 

My guess is, that you will be using far more time trying to make the hydrogen generator work, than using the torch.



The idea of making the generated gas expel one of the reactants to make the reaction self controlling is good (and an old one). Döbereiners Hydrogen Lighter was using it.





http://www.deutsches-museum.de

For the pretty large volumes you want for a reasonable torch, I do however think it would be quite a monster.


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## aflacglobal (Feb 13, 2010)

http://www.youtube.com/watch?v=w2DY1gSiEmM&NR=1


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## peter i (Feb 16, 2010)

aflacglobal said:


> http://www.youtube.com/watch?v=w2DY1gSiEmM&NR=1



Now there was a use for all those Al-turnings.


Environmentally sound disposal of the waste might cost more than the same amount of hydrogen in bottles, but it sure is a very nice gizmo!


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