Depending on the amount of the hydrogen generating material, the maximum H2 pressure achieved when filling gas cylinder, 1 litre in the internal volume, varied between 50 and 100 bar. The hydrogen generation time controlled by the supply of the acid solution was between 0.5 and 5 hours; in doing so at the same conditions hydrogen release when using MgH2 was 2.5 times faster than for Mg. Further increase of the hydrogen generation yield and rate can be achieved by the use of MgH2-GLM and MgH2-Ni/GLM composites studied in this work. We note that further shortening of the hydrogen generation time, first of all, depends on providing efficient heat removal from the hydrolysis reactor because during the tests the supply of citric acid solution into reactor was limited to avoid uncontrolled self-heating of the reaction solution.