The synthesis of active Mg by the thermal decomposition of Mg anthracene in vacuum is a method which does not consume any reagents in principle. This active Mg can be hydrogenated with the formation of MgH2 under normal pressure. The optimum temperature for the hydrogenation reaction is 230? The order of the hydrogenation reaction with respect to the Mg surface area is one. The apparent activation energy is 43 kJ/mol. The reason for the high activity of this Mg is closely related to its high dispersion and its large clean surface. Electron microscopy data reveal that the size of the primary particles of the active Mg belongs to the field of nano-materials.

Key words: MAGNESIUM, HYDROGENATION, THERMOLYSIS