About this Abstract |
Meeting |
MS&T21: Materials Science & Technology
|
Symposium
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2021 Undergraduate Student Poster Contest
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Presentation Title |
Thermal Analysis of Sodalite-immobilized Iodine-129 Caustic Scrubber Slurry |
Author(s) |
John M. Bussey, David Bollinger, Jessica Erickson, Natalie Smith-Gray, John S. McCloy |
On-Site Speaker (Planned) |
John M. Bussey |
Abstract Scope |
One modern challenge in nuclear fuel waste management is long-term disposal of Iodine-129 (<sup>129</sup>I). Issues include high groundwater mobility, long half-lives (15.7 million years), and incompatibility with typical vitrification technologies. Caustic scrubbers are planned to capture <sup>129</sup>I in an envisioned spent nuclear fuel reprocessing stream. One method utilizes incorporating <sup>129</sup>I in sodalite-type caged aluminosilicate minerals which can subsequently be Hot Isostatic Pressed (HIP) with binder glass for vitrified long-term storage. In characterizing mineralized caustic scrubber slurry, X-ray diffraction (XRD) is useful and somewhat limited. Promising supplemental methods include Differential Thermal Analysis (DTA) and Thermogravimetric Analysis (TGA) for measuring temperature-dependent heat and mass fluxes. Mixed-sodalites were hydrothermally synthesized and subsequently characterized with XRD, DTA, and TGA. DTA/TGA methods and corresponding analysis provided 1) phase identification complementing and verifying XRD results, 2) assignment and quantification of phase changes and volatilization events, and 3) essential insights for selecting HIP and glass binder parameters. |