Milestone Report - M4FT-15OR0312026 - Complete NO and NO2 aging of AgZ

Bruffey, Stephanie H.¹  Patton, Kaara K.¹  Walker, Jr, Joseph Franklin¹  Jubin, Robert Thomas¹ 

[1]Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

关键词: silver mordenite;    aging;    NO;    iodine;   

DOI  :  10.2172/1210142
RP-ID  :  ORNL/SPR--2015/128
PID  :  OSTI ID: 1210142
Others  :  Other: AF5805010
Others  :  NEAF327

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来源: SciTech Connect

【 摘 要 】

In an off-gas system within a nuclear fuel reprocessing plant, any capture material will be exposed to a gas stream for months at a time. This gas stream may be at elevated temperature and could contain water, NO_x gas, or a variety of other constituents that comprise the off-gas stream. For this reason, it is important to understand the effects of long-term exposure, or aging, on proposed capture materials. One material under consideration is silver-exchanged mordenite (AgZ). The aim of this study was to determine the effect of extended exposure at 150?��C to an air stream containing NO on the iodine capture capacity of the hydrogen reduced form of AgZ designated as Ag⁰Z. The study was originally also intended to expand on the static NO₂ aging studies by exposing Ag⁰Z to a flowing stream of NO₂ for an extended period of time, but those tests were delayed due to NO₂ production schedules by the gas vendor. Unreduced silver mordenite has a loading capacity of approximately 25 mg I/g AgZ and that capacity is increased to 100 mg I/g Ag⁰Z upon reduction. It appears that extended exposure of AgZ to 1% NO at 150?��C may not only neutralize the increased capacity gained by reduction, but perhaps degrade the sorbent even further. Loss of 80% of sorbent capacity and surface area was observed after 8 weeks of exposure to a 1% NO stream at 150?��C. Investigations continue into the effects of aging by off-gas components on iodine sorbents. Future work will age silver mordenite with streams containing NO₂. As the simulated off-gas streams become more complex and more corrosive, the ability of AgZ to withstand conditions present in off-gas streams will be more fully known.