Kinetics and mechanism of MgH2 hydrolysis in MgCl2 solutions

In the present work we systematically studied hydrolysis of magnesium hydride in MgCl2 aqueous solutions, which was used as a process promotor. The initial rate, pH reaction mixture, and overall yield are all found to be linearly dependent logarithm concentration. phase-structural elemental compositions formed precipitates showed that they do not contain chlorine ions solely consist Mg(OH)2. size Mg(OH)2 crystallites increased with increasing content solution. best agreement between observed modelled kinetics achieved by applying pseudo-homogeneous model describes rate H+ deposition is impermeable water blocks surface remaining MgH2 however simultaneously partially suspends this reaction. We therefore propose mechanism presence based on comparison kinetic dependencies, variations solutions structural analysis data for solid deposits during interaction. furthermore define process, equation variation containing chloride salts. Hydrolysis efficiency relative amount; performance being stoichiometric ratio MgH2+0.7MgCl2 (MgCl2/MgH2 weight 12.75/100). This provided hydrogen 1025 mL (H2)/g MgH2. Maximum peaked at 89% theoretical H2 generation capacity, within 150 min start, 35% released first 10 after high 800 min?1·g?1