摘要
Li4SiO4 ceramic pebble is considered as a candidate tritium breeding material of Chinese Helium Cooled Solid Breeder Test Blanket Module （CH HCSB TBM） for the International Thermonuclear Experimental Reactor （ITER）. In this paper, LiaSiO4 ceramic pebbles deposited with catalytic metals, including Pt, Pd, Ru and Ir, were prepared by wet impregnation method. The metal particles on Li4SiO4 pebble exhibit a good promotion of hydrogen isotope exchange reactions in H2-D20 gas system, with conversion equilibrium temperature reduction of 200-300 ~C. The out-of-pile tritium release experiments were performed using 1.0 wt% Pt/Li4SiO4 and Li4SiO4 pebbles irradiated in a thermal neutron reactor. The thermal desorption spectroscopy shows that Pt was effective to increase the tritium release rate at lower temperatures, and the ratio of tritium molecule （HT） to tritiated water （HTO） of 1.0 wt% Pt/LiaSiO4 was much more than that of Li4SiO4, which released mainly as HTO. Thus, catalytic metals deposited on LiaSiO4 pebble may help to accelerate the recovery of bred tritium particularly in low temperature region, and increase the tritium molecule form released from the tritium breedin~ materials.
Li4SiO4 ceramic pebble is considered as a candidate tritium breeding material of Chinese Helium Cooled Solid Breeder Test Blanket Module （CH HCSB TBM） for the International Thermonuclear Experimental Reactor （ITER）. In this paper, LiaSiO4 ceramic pebbles deposited with catalytic metals, including Pt, Pd, Ru and Ir, were prepared by wet impregnation method. The metal particles on Li4SiO4 pebble exhibit a good promotion of hydrogen isotope exchange reactions in H2-D20 gas system, with conversion equilibrium temperature reduction of 200-300 ~C. The out-of-pile tritium release experiments were performed using 1.0 wt% Pt/Li4SiO4 and Li4SiO4 pebbles irradiated in a thermal neutron reactor. The thermal desorption spectroscopy shows that Pt was effective to increase the tritium release rate at lower temperatures, and the ratio of tritium molecule （HT） to tritiated water （HTO） of 1.0 wt% Pt/LiaSiO4 was much more than that of Li4SiO4, which released mainly as HTO. Thus, catalytic metals deposited on LiaSiO4 pebble may help to accelerate the recovery of bred tritium particularly in low temperature region, and increase the tritium molecule form released from the tritium breedin~ materials.
基金
supported by the Development Fund of China Academy of Engineering Physics (No.2010B0301035)
the National Magnetic Confinement Fusion Science Program (No. 2010GB112004)
