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Title: Performance testing of aged hydrogen getters against criteria for interim safe storage of plutonium bearing materials.

Abstract

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 hydrogen getter HITOP was aged for 3 months at 70 C and tested under both recombination and hydrogenation conditions at 20 and 70 C; partially saturated and irradiated aged getter samples were also tested. The recombination reaction was found to be very fast and well above the required rate of 45 std. cc H2h. The gettering reaction, which is planned as the backup reaction in this deployment, is slower and may not meet the requirements alone. Pressure drop measurements and {sup 1}H NMR analyses support these conclusions. Although the experimental conditions do not exactly replicate the deployment conditions, the results of our conservative experiments are clear: the aged getter shows sufficient reactivity to maintain hydrogen concentrations below the flammability limit, between the minimum and maximum deployment temperatures, for three months. The flammability risk is further reduced by the removal of oxygen through the recombination reaction. Neither radiation exposure nor thermal aging sufficiently degrades the getter to be a concern. Future testing to evaluate performance for longer aging periods is in progress.

Authors:
; ;
Publication Date:
Research Org.:
Sandia National Laboratories
Sponsoring Org.:
USDOE
OSTI Identifier:
901710
Report Number(s):
SAND2007-0095
TRN: US0702727
DOE Contract Number:
AC04-94AL85000
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
08 HYDROGEN; AGING; BEARINGS; FLAMMABILITY; GETTERING; GETTERS; HYDROGEN; HYDROGENATION; OXYGEN; PERFORMANCE TESTING; PLUTONIUM; PRESSURE DROP; RADIATIONS; RECOMBINATION; REMOVAL; STORAGE; TESTING; Getters.; Hydrogen.; Plutonium-Storage.

Citation Formats

Shepodd, Timothy J., Nissen, April, and Buffleben, George M. Performance testing of aged hydrogen getters against criteria for interim safe storage of plutonium bearing materials.. United States: N. p., 2006. Web. doi:10.2172/901710.
Shepodd, Timothy J., Nissen, April, & Buffleben, George M. Performance testing of aged hydrogen getters against criteria for interim safe storage of plutonium bearing materials.. United States. doi:10.2172/901710.
Shepodd, Timothy J., Nissen, April, and Buffleben, George M. Sun . "Performance testing of aged hydrogen getters against criteria for interim safe storage of plutonium bearing materials.". United States. doi:10.2172/901710. https://www.osti.gov/servlets/purl/901710.
@article{osti_901710,
title = {Performance testing of aged hydrogen getters against criteria for interim safe storage of plutonium bearing materials.},
author = {Shepodd, Timothy J. and Nissen, April and Buffleben, George M.},
abstractNote = {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 hydrogen getter HITOP was aged for 3 months at 70 C and tested under both recombination and hydrogenation conditions at 20 and 70 C; partially saturated and irradiated aged getter samples were also tested. The recombination reaction was found to be very fast and well above the required rate of 45 std. cc H2h. The gettering reaction, which is planned as the backup reaction in this deployment, is slower and may not meet the requirements alone. Pressure drop measurements and {sup 1}H NMR analyses support these conclusions. Although the experimental conditions do not exactly replicate the deployment conditions, the results of our conservative experiments are clear: the aged getter shows sufficient reactivity to maintain hydrogen concentrations below the flammability limit, between the minimum and maximum deployment temperatures, for three months. The flammability risk is further reduced by the removal of oxygen through the recombination reaction. Neither radiation exposure nor thermal aging sufficiently degrades the getter to be a concern. Future testing to evaluate performance for longer aging periods is in progress.},
doi = {10.2172/901710},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}

Technical Report:

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