Controllable hydrogen release via aluminum powder corrosion in calcium hydroxide solutions

Mechanism of aluminum powder corrosion in calcium hydroxide solutions was investigated via various analyses of residues after its hydrolysis reaction and pH change of the solutions to control the release of hydrogen gas. It was revealed that the reaction with a release of hydrogen gas consisted of katoite formation and hydration of aluminum. The katoite formation, which is progressed by the reaction among calcium ion, aluminum hydroxide anion (Al(OH)4−), and water molecules at the first step, is important for the promotion of aluminum corrosion and moderate release of hydrogen gas.