Step 4: Recovery of Liquid Metal
Initially, I used to filter the alumina and squeeze the liquid metal out. Obviously some remained in the Alumina cake.
So I dissolved the alumina in a solution of NaOH, caustic soda, (you can use Drano). The liquid metal precipitated immediately.
This shows almost 100% recovery of liquid metal which makes this type of reaction economically sustainable.
In the hydrogen economy, separation of the gallium will be done at the power plant. The alumina is reduced back to aluminum using the Hall-Heroult process. The first aluminum plant in history was powered by the Niagara falls, a green source of energy.
However, this instructable can be scaled for individual use. The amount of gallium to proceed the reaction is small and recoverable. Ardent green energy enthusiasts can run their car and home using this instructable.