The function of Sn(II)-apatite as a Tc immobilizing agent

JOURNAL OF NUCLEAR MATERIALS

卷:480

Article

Asmussen, R. Matthew¹  Neeway, James J.¹  Lawter, Amanda R.¹  Levitskaia, Tatiana G.¹  Lukens, Wayne W.²  Qafoku, Nikolla P.¹ 

[1] Pacific Northwest Natl Lab, Energy & Environm Directorate, 902 Battelle Blvd, Richland, WA 99352 USA

[2] Lawrence Berkeley Natl Lab, Div Chem Sci, Berkeley, CA 94720 USA

关键词: Technetium;    Nuclear waste;    X-ray absorption spectroscopy;    Waste forms;    Hanford;   

DOI  :  10.1016/j.jnucmat.2016.09.002

来源: Elsevier

【 摘 要 】

At the U.S. Department of Energy Hanford Site, Tc-99 is a component of low-activity waste (LAW) fractions of the nuclear tank waste and removal of Tc from LAW streams would greatly benefit the site remediation process. In this study, we investigated the removal of Tc(VII), as pertechnetate, from deionized water (DIW) and a LAW simulant through batch sorption testing and solid phase characterization using tin (II) apatite (Sn-A) and SnCl2. Sn-A showed higher levels of Tc removal from both DIW and LAW simulant. Scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/XEDS) and X-ray absorption spectroscopy (XAS) of reacted Sn-A in DIW showed that TcO4- is reduced to Tc(IV) on the Sn-A surface. The performance of Sn-A in the LAW simulant was lowered due to a combined effect of the high alkalinity, which lead to an increased dissolution of Sn from the Sn-A, and a preference for the reduction of Cr(VI). (C) 2016 Elsevier B.V. All rights reserved.

【 授权许可】

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