Study on hydrogen generation from the hydrolysis of a ball milled aluminum/calcium hydride composite

Metal Al was ball milled with CaH2 to improve its hydrolysis properties. The effects of reaction temperature and milling conditions on the hydrogen generation performances of Al are investigated. A higher temperature has been shown to be beneficial for the hydrolysis of Al-CaH2 composites. With increasing the added amount of CaH2 and milling time, the grain size of Al is decreased and the protective oxide film on the surface of the Al powder is damaged. The hydrolysis of CaH2 helps to open up the structure of Al grains and provide OH- to enhance the corrosion of Al. As a result, the hydrogen production of Al powder has been greatly optimized, and the addition of CaH2 proves to be more effective than the addition of some other hydrides. The yield and maximum hydrogen generation rate (mHGR) of an Al-10 mol% CaH2 mixture milled for 15 h are 97.8% and 2074.3 mL min(-1) g(-1), respectively.