Thermit Reaction: Electrical Energy from Al + Fe2O3

[Uno Lee]

I was wondering if it would be possible to create electrical energy directly instead of heat and light in this exothermic reaction. Al + Fe2O3 = Fe + Al2O3 (Sorry "=" sign should be an arrow) What sort of electrolyte should be used?

 

[Uno Lee]

Oops, that's 2Al + Fe2O3 > 2Fe + Al2O3

 

[so-crates]

Well Fe2O3 is not water soluble, so you would need something to solvate Fe3+ ions. I think H2SO4 would work. Stick an aluminum anode in aqueous solution of Fe2O3. For the cathode, you wouldn't necessarily need to use iron.

 

[Uno Lee]

Thanks, I'll try this but by little book of solubilities says that Fe2O3 is only soluble in HCl and that (unfortunately) dissolves Al, too.

 

[Uno Lee]

Well Fe2O3 is not water soluble, so you would need something to solvate Fe3+ ions. I think H2SO4 would work. Stick an aluminum anode in aqueous solution of Fe2O3. For the cathode, you wouldn't necessarily need to use iron.

I want to stick to commonly found materials and keep it as non-toxic as possible. Aluminum is a commonly found material, that takes a lot of electricity to make. I'm looking for a way of getting that electricity back.

 

[so-crates]

Thanks, I'll try this but by little book of solubilities says that Fe2O3 is only soluble in HCl and that (unfortunately) dissolves Al, too.

It dissolves alumnium salts or does it react with alumimun metal? If the former, then it shouldn't be a problem. I forgot where alumimum was on the activity series for aqueous solutions but I believe it was below hydrogen so it shouldn't be a problem.

What were you planning on using for your alumnium block? Foil ?

 

[Uno Lee]

Foil to test (greater surface area for reaction) then I want to try used pop and beer cans before moving up to aluminum campers and trailers.

 

[so-crates]

Actually now that I think about you might run into a problem because the sulfic acid will react with oxide to form water.