Publications

Update to SAND2007-0095, SAND2007-1789P, and SAND2007-7165P: 18-Month 70°C Aging Study of HiTop Hydrogen Getter for WSRC

Buffleben, George M.; Nissen, April E.; Shepodd, Timothy J.

Hydrogen getters were tested for use in storage of plutonium-bearing materials in accordance with DOE's Criteria for Interim Safe Storage of Plutonium Bearing Materials. The original studies, documented in Sandia Report SAND2007-0095, included HiTop getter material aged for 3 months at 70°C. This material was aged for an additional 3 months for a total of 6 months at 70°C, and the performance of the getter was evaluated again and documented in Sandia Report SAND2007-1789P. This material was then aged for an additional 7 months for a total of 13 months at 70°C, and the performance of the getter under recombination and gettering conditions was evaluated. A sample of the 13 months aged getter was exposed to radiation at SRNL, and the performance of this sample was also evaluated. The results of the 13 months study is reported in SAND2007-7165P. The HiTop material was aged for an additional 5 months for a total of 18 months. This material was split into two samples with the second sample being exposed to radiation at SRNL. The performance of the 18 month aged HiTop material is covered in this report. The 18-month aged material showed similar performance under gettering conditions to the previously aged material: the recombination rate is well above the required rate of 45 std. cc H₂/h, and the gettering reaction occurs in the absence of oxygen at a slower rate. Both pressure drop measurements and ¹H NMR analyses support these conclusions. ¹H NMR analyses show extremely minor changes in the 18-month aged material, which can be possibly attributed to slight decomposition of the HiTop material or absorption of contaminants during the aging process.