Investigation of characteristics on PdY8.5Ru0.19 alloy absorbing-desorbing hydrogen and deuterium

The pressure-composition isotherms of PdY8.5Ru0.19-alloy's absorbing-desorbing H-2 and D-2 were experimentally measured at temperature range of 25 to 100 degrees C. Comparing with the Pd, the results show that the gas phase pressure becomes lower, and that the width of the plateau becomes narrower. The isotope effects in PdY8.5Ru0.19-hydyogen interaction are noticeable, while the hysteresis is smaller. An analytical expression is found to describe The pressure-composition isotherms of PdY8.5Ru0.19-alloy's absorbing-desorbing H-2 and D-2: p=A(e(r/B)-1). The D-2 adsorption enthalpy Delta H is -13.9 kJ/mol .D-2, entropy Delta S is -9.4,J/mol (KD2)-D-.. The rate curves of absorbing H-2 and D-2 were measured at 25 degrees C, and the dynamics constant of them is K-H=2.39 x 10(-4) mol(.)s(-1), K-D=1.16 x 10(-4) mol(.)s(-1) respectively. The model of the gradual conversion can describe the behavior of H-2 absorption.