Disproportionation Characteristics of a Zirconium-Cobalt Hydride Bed under ITER Operating Conditions

Effects of temperature and hydrogen pressure on the activation behavior of ZrCo

“…As well-known, the disproportionation of ZrCoH 3 into ZrH 2 and ZrCo 2 , which will result in serious degradation of hydrogen storage properties, is easily induced under relatively high hydrogen pressure and high temperature [33,34]. Fortunately, the disproportionation products including ZrH 2 and ZrCo 2 were not observed in the XRD results in this study for the first hydrogenation at different temperatures.…”

Fusion tritium research facilities in KAERI

“…We have been developing ZrCo beds for nuclear fusion fuel cycle plants [5][6][7][8][9][10][11][12][13][14]. However due to the incomplete reproportionation characteristic of zirconium-cobalt, uranium was recommended to be employed as a way to store hydrogen isotopes as metal hydride [15].…”

Fusion fuel gas recovery and delivery characteristics on a tray-type ZrCo bed

“…Because of enhanced disproportionation reaction [8], high pressure in the ZrCo hydride bed at an elevated temperature above 300 • C should be avoided for the rapid delivery of tritium during D-T plasma operation. Three experimental runs of high pressure delivery, however, were carried out to examine whether the high pressure delivery method can achieve a higher delivery rate of 20 Pa m 3 /s.…”

“…Highest delivery rate of approximately 2.1 Pa m 3 /s was achieved by a small bed model of the SDS bed. The design of this bed model is characterized by a horizontal thin cylindrical layer (3-7 mm in thickness) of ZrCo powder packed bed surrounded by a large cylindrical filter and by a large heating surface per unit weight of ZrCo to mitigate a large temperature change in the ZrCo hydride bed due to the exothermic and endothermic reaction heat (ZrCo + x/2H 2 = ZrCoHx + H, H = 73-81 kJ/mol-H 2 ) accompanied by hydrogen recovery and delivery [6][7][8].…”