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The activation of aluminum with low melting gallium based alloys makes it possible to obtain a material easily oxidizable by water at room temperature to release ~1.2 L of pure hydrogen per 1 g of metal. The kinetics and regularities of the interaction of activated alumi num with water were studied as a function of the amount and composition of metal activators, dispersity of the powder, and temperature. The phase composition of the solid reaction products was shown by X ray diffraction analysis to depend on temperature and duration of the process.Substantial increase in the cost of traditional energy carriers enforced noticeable intensification of works on search for alternative energy sources including those related to the use of hydrogen. However, the use of this energy carrier requires the development of new methods for preparation, storage, and transportation of hydrogen and methods and devices for the direct conversion of fuel to energy. Among the problems considered, the develop ment of safe and economically viable methods for prepa ration, storage, and transportation of hydrogen is most topical and at the same time most complicated.A possible route for the complex solution of these problems is related to the use of metals and their alloys and to the synthesis of hydrogen directly at the site of consumption. Economical and ecological considerations as well as physicochemical properties allows one to dis tinguish aluminum among all metals and alloys, because the oxidation of 1 g of aluminum with water gives 1.244 L of hydrogen.It is well known that under standard conditions alumi num is covered with very thin but dense oxide film pre venting the reaction of aluminum with water. Aluminum can be activated by various methods, for example, amal gamation, 1 oxidation in alkaline media, 2 and high tem * Dedicated to Academician I. I. Moiseev on the occasion of his 80th birthday. perature oxidation. 3 However, several drawbacks of these methods make them inappropriate for the creation of generators of hydrogen for domestic purposes.The addition of gallium based alloys with low melting temperatures (gallam) 4,5 to metallic aluminum leads to the destruction of the surface oxide layer 6-9 (Rebinder effect) and imparts high reactivity toward water, alcohols, and several functionalized hydrocarbons to the metal. 10,11 Depending on the oxidation reaction conditions, first of all on the temperature, different solid products (oxides, hydroxides) can be obtained at the same yield of hydrogen 12 2 Al + 3 H 2 O = Al 2 O 3 + 3 H 2 + Q (1) (15.1 MJ (kg Al) -1 ), 2 Al + 4 H 2 O = 2 AlOOH + 3 H 2 + Q (2) (15.5 MJ (kg Al) -1 ), 2 Al + 6 H 2 O = 2 Al(OH) 3 + 3 H 2 + Q (3) (16.3 MJ (kg Al) -1 ).Reaction (1) occurs if the metal is oxidized with water and/or water vapor at temperatures of the reaction mixture higher than 200-250 °С, whereas reactions (2) and (3) occur at lower temperatures.We have previously 13 developed the method for the preparation of the activated aluminum powder. The