Increasing Tc retention during nuclear waste vitrification: Effect of alumina source on the rate of rhenium incorporation into glass

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985891%3A_____%2F25%3A00636319" target="_blank" >RIV/67985891:_____/25:00636319 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/60461373:22310/25:43933311 RIV/60461373:22810/25:43933311

Výsledek na webu

<a href="https://doi.org/10.1016/j.jnucmat.2025.155916" target="_blank" >https://doi.org/10.1016/j.jnucmat.2025.155916</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.jnucmat.2025.155916" target="_blank" >10.1016/j.jnucmat.2025.155916</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Increasing Tc retention during nuclear waste vitrification: Effect of alumina source on the rate of rhenium incorporation into glass

Popis výsledku v původním jazyce

Technetium (Tc) volatilization during nuclear waste vitrification poses a significant challenge, necessitating recycle loops that may lead to reduced waste loading in the glass, or secondary Tc treatment in alternative waste forms. Thus, reducing the volatilization of Tc (or Re, its non-radioactive surrogate) is crucial for improving vitrification process efficiency and minimizing the long-term costs associated with nuclear waste management. In our previous study, we demonstrated that using gibbsite, instead of kyanite, as the alumina source in low-activity nuclear waste melter feeds increased the Re retention by up to 20 %, a result attributed to the formation of nanocrystalline alumina in the gibbsite-containing melter feeds. In this work, we show that using boehmite, another Al-source that forms nanocrystalline alumina polymorphs upon heating, results in an even higher retention of Re, by up to 25 %. Using X-ray diffraction and deionized water leaching tests on heat-treated feed samples, we analyzed the compositions of soluble oxyanionic salt phase and the insoluble glass-forming phase as a function of temperature, and evaluated the rate of Re incorporation into the developing transient alkali-alumino-borosilicate melt. We found that the formation of nanocrystalline alumina in the boehmite-containing feed occurred at temperatures approximately 100 °C lower than in the gibbsite feed, accelerating reactions between alumina, oxyanionic salts, and the borosilicate melt, which likely accounts for the enhanced Re retention in the boehmite-containing feeds.

Název v anglickém jazyce

Increasing Tc retention during nuclear waste vitrification: Effect of alumina source on the rate of rhenium incorporation into glass

Popis výsledku anglicky

Technetium (Tc) volatilization during nuclear waste vitrification poses a significant challenge, necessitating recycle loops that may lead to reduced waste loading in the glass, or secondary Tc treatment in alternative waste forms. Thus, reducing the volatilization of Tc (or Re, its non-radioactive surrogate) is crucial for improving vitrification process efficiency and minimizing the long-term costs associated with nuclear waste management. In our previous study, we demonstrated that using gibbsite, instead of kyanite, as the alumina source in low-activity nuclear waste melter feeds increased the Re retention by up to 20 %, a result attributed to the formation of nanocrystalline alumina in the gibbsite-containing melter feeds. In this work, we show that using boehmite, another Al-source that forms nanocrystalline alumina polymorphs upon heating, results in an even higher retention of Re, by up to 25 %. Using X-ray diffraction and deionized water leaching tests on heat-treated feed samples, we analyzed the compositions of soluble oxyanionic salt phase and the insoluble glass-forming phase as a function of temperature, and evaluated the rate of Re incorporation into the developing transient alkali-alumino-borosilicate melt. We found that the formation of nanocrystalline alumina in the boehmite-containing feed occurred at temperatures approximately 100 °C lower than in the gibbsite feed, accelerating reactions between alumina, oxyanionic salts, and the borosilicate melt, which likely accounts for the enhanced Re retention in the boehmite-containing feeds.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20504 - Ceramics

Projekt

<a href="/cs/project/GA24-11616S" target="_blank" >GA24-11616S: Vliv redukčních činidel a sklo-tvorných přísad na chování rhenia and jeho retenci při vitrifikaci jaderného odpadu</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2025

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Nuclear Materials

ISSN

0022-3115

e-ISSN

1873-4820

Svazek periodika

614

Číslo periodika v rámci svazku

August

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

9

Strana od-do

155916

Kód UT WoS článku

001502433900001

EID výsledku v databázi Scopus

2-s2.0-105005954546