Research Programs to Investigate the Fundamental Chemistry of Technetium

Shuh, David K. ; Burns, Carol J. ; Lukens, Wayne W. Jr.

Lawrence Berkeley National Laboratory

关键词: Research Programs;    12 Management Of Radioactive Wastes, And Non-Radioactive Wastes From Nuclear Facilities;    Waste Forms;    Half-Life;    37 Inorganic, Organic, Physical And Analytical Chemistry;   

DOI  :  10.2172/834462
RP-ID  :  EMSP-73778-2002
RP-ID  :  834462

美国|英语

来源: UNT Digital Library

【 摘 要 】

Technetium (99Tc, half-life = 2.13x105 years, b-emitter) is one of the radionuclides of major concern for nuclear waste disposal. This concern is due to the long half-life of 99Tc, the ease with which pertechnetate, TcO4 -, migrates in the geosphere, difficulties in incorporating technetium into glass waste forms, and the corresponding regulatory considerations. The problem of mobility of pertechnetate in the environment is compounded by the fact that pertechnetate is the thermodynamically stable form of technetium in oxidizing environments. Because of this stability, pertechnetate was presumed to be the predominant chemical form of technetium in the aqueous phase of nuclear waste tanks. However, studies have indicated that a significant fraction of the technetium is in a different chemical form. These factors present challenges for the separation and immobilization of technetium. The objective of this research project is to provide new knowledge about the chemical behavior of technetium so that the factors underlying technetium speciation in nuclear waste and in waste forms can be understood and the problems can be addressed.