Chemistry lesson

Way back in high school, I wanted to be a chemist.  Why?  Who the hell knows, I forgot.  Now, what little chemistry I did know, I forgot that too.  It would come in handy about now.

The reason is I'm studying Aronsson's idea to use a chemical reaction in order to produce hydrogen for his fuel cells.  At first, this idea didn't seem so good, but it is starting to look better to me.

The process involves the use of a potassium hydroxide solution and aluminum.  The aluminum dissolves in the solution, releasing hydrogen.  In so doing, it collects in the solution as aluminum hydroxide.  The idea then occurred to me that if you were to get back to aluminum oxide, you can regenerate the aluminum and start the whole process over again.

It so happens that this is how aluminum is actually obtained.  Aluminum oxide is obtained through the process of calcination---described thusly:

The raw material bauxite reacts with caustic soda to aluminium hydroxide. Rotary kilns are used to convert aluminium hydroxide into aluminium oxide by driving off water.
Next to the calcination, the aluminium oxide undergoes an electrolytic process to gain aluminium.

With the production of hydrogen and aluminum hydroxide, we are already one step ahead.  So all that's remains is to heat it up in the kiln to drive off water.  Uh, oh!  I forgot something.

What about the potassium hydroxide?  That's mixed in with the aluminum hydroxide, so you need to separate it.  I've read up a bit on that, but I don't see how that is done.  Provided that you can get back to two separated chemicals, potassium hydroxide and alumnium hydroxide, then you are back where you started after getting the aluminum regenerated.

The purpose of all this is to make a closed loop system for generating hydrogen.  You would need a water source.  Actually, it is only the water that gets consumed--- if I am not mistaken.

The aluminum goes into the potassium hydroxide and dissolves into aluminum hydroxide.  As it does this, it releases hydrogen.  The hydrogen can be collected and subsequently recombined in a fuel cell so as to get the water again, plus electricity.  Since the water will be generated in another location, that is why you will need a water source where the hydrogen can be generated.  Provided that the potassium hydroxide and aluminum hydroxide can be separated without too much trouble, the whole process can take place in a closed loop.

The input would be water and an energy source.  The outputs would be hydrogen gas.  The rest of the chemicals are recycled.

Now, I got the impression that Aronsson wants to put this electrolyzer on a car.  Well, maybe all of this is too complex for a car.  You can produce the hydrogen at a plant and use it to refuel the car.  Or you can combine the hydrogen with nitrogen to make ammonia and tranport the ammonia to another site which will crack it into hydrogen and nitrogen.

You'll run your fuel cell with the hydrogen thus produced.  Either at the plant or the refueling station.  There's no need for any problem in getting hydrogen fuel for your fuel cell car.