Tellurite glasses for vitrification of technetium-99 from pyrochemical processing
2017; Elsevier BV; Volume: 493; Linguagem: Inglês
10.1016/j.jnucmat.2017.05.052
ISSN1873-4820
AutoresJae‐Young Pyo, Cheong Won Lee, Hwan-Seo Park, Jae Hwan Yang, Wooyong Um, Jong Heo,
Tópico(s)Luminescence Properties of Advanced Materials
ResumoA new alkali-alumino tellurite glass composition was developed to immobilize highly-volatile technetium (Tc) wastes generated from the pyrochemical processing technology. Tellurite glass can incorporate up to 7 mass% of rhenium (Re, used as a surrogate for Tc) with an average retention of 86%. Normalized elemental releases evaluated by seven-day product consistency test (PCT) satisfied the immobilized low activity waste requirements of United States when concentration of Ca(ReO4)2 in the glass was <12 mass%. Re ions form Re7+ and are coordinated with four oxygens to form ReO4− tetrahedra. These tetrahedra bond to modifiers such as Ca2+ or Na+ that are further connected to the tellurite glass network by Ca2+ (or Na+) – non-bridging oxygen bonds.
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