Object under investigation: development of energy–storing substances (ESS) based on activated aluminum, magnesium, silicon, boron and their silicides for the extraction of hydrogen from water at a high rate and development of highly efficient technologies for hydrogen production from water.
Aim of the work: study of the activation of aluminum and magnesium to them reactivity in the reaction of hydrogen evolution from water. Study of the kinetics and mechanism of the interaction of activated aluminum and magnesium with water in a temperature range of 473-598 K and the effect of additions of metals–activators of different nature on the reaction rate of hydrogen evolution from water in a reactor with automatic monitoring of hydrogen evolution rate and pressure.
Methods of investitigation: volumetry, gravimetry, electron microscopy, thermochemical and kinetic methods for the investigation of solid–phase reactions in ESS–water systems at 473-598 K and a hydrogen of up to 200 atm. Aluminum and magnesium were activated with help such metals–activators.
The kinetics and mechanism of the interaction of four–component systems and a five–component system with water with hydrogen evolution in a temperature rance of 200–325C have been studied by the volumetric method at high pressures and temperatures. It has been found that the rate of hydrogen extraction from water with four–component systems and a five–component system in the case of interaction with water at 325C is 76-93, 16870-24138 and 11947-21650 L/(m2min) respectively. The rate constants of interaction with water for the four–component systems and the five–component system have been determined, which are at 325C 0.021-0.016, 2.253-10.026 and 3.270-4.325 min-1 respectively.
Metallographic investigations of the surfaces of fresh fractures of the four–component systems and the five– component system have been carried out using scanning electron microscopes JSM6490LV (Japan) and ZEISS EVO 50 XVP. It has been sound that when aluminum– and magnesium–base alloys are fabricated, globules of size 2-12 mm and nanostructured matrices of the base metals of alloys are formed.
Keywords: Key words: hydrogen, reaction kinetics, reaction mechanism, rate constant, activation energy of reactions, temperature, pressure, reactor for the investigation of reactions at high pressure and high temperatures, electron microscopy.