Activation Energy of Diffusion of H in Pd_(81)Pt_(19) Membrane during Absorption and Desorption of H

摘要

The diffusion coefficient of hydrogen were determined for Pd_(81)Pt_(19) membrane by fitting the theoretical expressions to the experimental data p(t) (the pressure of hydrogen after permeation through the wall of membrane as a function of time) at five different temperatures in the range 273-308 K. The measurements were carried out during absorption and desorption of hydrogen in membrane with initial content of hydrogen n_0 ≈ 0.011 (n = H/M atomic ratio of hydrogen to metal). The changes in hydrogen pressure at outer side of membrane corresponded to |△n| ≈ 0.0036 during absorption and desorption of hydrogen. For the first time, the activation energies of diffusion of hydrogen were determined for Pd_(81)Pt_(19) membrane in absorption and desorption processes, in which influences of stresses were taken into account.