Discussion of low cost hydrogen methods

[lplchem]

I would like to explore possibilities of production of really cheap hydrogen by finding a substitute for scrap aluminum in the current hydrogen on-demand known reaction:

2Al + 6H₂O -> 2Al(OH)₃ + 3H₂ (catalyzed by specially treated carbon, carried out at 85 °C.)

The above reaction is scalable from small rate and pressure to very high rate and pressure.

(I hope the subscripts worked out OK).

It is highly advantageous in this discussion to start out with something that is highly abundant.

 

[chemisttree]

Without knowing the restrictions you are interested in... try this. I would think a low temperature process for the gas water shift reaction is much cheaper than aluminum/ water if you take into account the high cost of manufacturing the metal.

 

[lplchem]

Thank you for the reference article. Of course, one must consider the cost of the gold, and the role this would have on the overall cost of operating in such a way. Obviously, there does not seems to be a way of reducing the cost of scrap aluminum (a substantial portion of which actually does not get recycled). Other metals come to mind including magnesium, the Cr-Nd:YAG laser (solar-pumped), see the HELIOS project design, but I could not get much information on the actual reactor where MgO is converted back to Magnesium (and oxygen). For instance, how do they intend to prevent the Mg and O2 from simply reacting as the products leave the high temperature zone?

 

[epenguin]

You are not producing energy, nor saving the world by saving on CO₂ production surely? Because first you have to make your aluminium from an oxidised form of the element, a notoriously energy-intensive process.

Maybe there are positive economics from the transportability etc. of the hydrogen. Or maybe the collection of all the aluminium foil and old pans we throw away can be organised?