An Assessment of Initial Leaching Characteristics of Alkali-Borosilicate Glasses for Nuclear Waste Immobilization

Abstract

Initial leaching characteristics of simulated nuclear waste immobilized in three alkali- borosilicate glasses (ABS-waste) were studied. The effects of matrix composition on the containment performance and degradation resistance measures were evaluated. Normalized release rates are in conformance with data reported in the literature. High Li and Mg loadings lead to the highest initial de-polymerization of sample ABS-waste (17) and contributed to its thermodynamic instability. Ca stabilizes non-bridging oxygen (NBO) and reduces the thermodynamic instability of the modified matrix. An exponential temporal change in the alteration thickness was noted for samples ABS-waste (17) and Modified Alkali-Borosilicate (MABS)-waste (20), whereas a linear temporal change was noted for sample ABS-waste (25). Leaching processes that contribute to the fractional release of all studied elements within the initial stage of glass corrosion were quantified and the main controlling leach process for each element was identified. As the waste loading increases, the contribution of the dissolution process to the overall fractional release of structural elements decreases by 43.44, 5.05, 38.07, and 52.99% for Si, B, Na, and Li respectively, and the presence of modifiers reduces this contribution for all the studied metalloids. The dissolution process plays an important role in controlling the release of Li and Cs, and this role is reduced by increasing the waste loading.

Development and Application of an Intelligent Test System for the Model Test on Deep Underground Rock Caverns

“…The safe disposal of HLW is a major issue to ensure environmental protection and the sustainable development of the nuclear energy industry; it is also an equally important issue regarding nuclear safety [2]. Deep-buried geological disposal is accepted worldwide as the safest and most feasible way to protect human beings and the environment [3][4][5][6][7].…”

Composition‐dependent leaching behavior in ion‐irradiated borosilicate glasses: A corrosion mechanism study

“…20 Furthermore, the composition of the glass itself plays a crucial role in determining its leaching behavior. 21 The effects of irradiation on glasses of different compositions under leaching conditions have garnered significant attention, underscoring the need for more in-depth studies on the corrosion mechanisms of various irradiated borosilicate glasses.…”