The permeability of hydrogen in bulk palladium membranes (approximately 1-mm thickness) was determined for the first time at conditions of simultaneously elevated temperature (623-1173 K) and hydrogen pressure (0 .1 x 106 to 2.76 x 106 Pa) .

When the hydrogen partial pressure exponent value was constrained to a value of 0 .5, the permeability was described by an Arrhenius-type relation where the pre-exponential constant and activation energy for this correlation were 1 .92 x 10 -7 mol/(m s Pao.50) and 13 .81 kJ/mol, respectively. These Arrhenius values were in good agreement with prior low-pressure correlations.