  The observable results for desorption kinetics by powder of metal hydride on
the example of mangesium hydride are reproduced with the model formulated in
terms of specific surface of powder. A volumetric measurement of hydrogen
desorption process is evaluated on an example of wet ball milled magnesium
hydride, and can be applied generally for any metal hydride.
  The exact solution of the model reproduces the shape of experimental curves
for desorption process providing a satisfying agreement with experimental data.
