Measuring the gas permeability of a metal hydride bed of the $\rm{LaNi}_5$ type alloy

We have tested the neutral, against the sorption material, gas (nitrogen) in the PXO8 metal hydride reactor containing $1$ kg of the $\rm{LaNi}_{4.8}\rm{Mn}_{0.3}\rm{Fe}_{0.1}$ alloy and have calculated the viscous permeability coefficient: $k = 0.42 \pm 0.08\,\mu$m$^2$.