Viscosities and working region predictions for bismuth aluminoborosilicate glasses

Abstract

Bismuth aluminoborosilicate glasses were prepared using a standard melt-quench technique, and the viscosity and thermal properties were measured and analyzed. Electron microprobe analysis was used to examine glass homogeneity. Fragility was calculated based on Mauro-Yue-Ellison-Gupta-Allan model fits to the viscosity curves. The system is characterized by an open structure with high fragility (44)(45)(46)(47)(48)(49)(50)(51)(52)(53)(54)(55)(56)(57)(58)(59). Based on microanalysis and differential scanning calorimetry results, the addition of network intermediate Al 2 O 3 appears to mitigate both phase separation and crystallization. From thermal property data, mixture models were created to predict the glass transition temperatures and softening temperatures as functions of composition. Based on K-fold validation findings, the first-order mixture model predictions of glass transition and softening appear to approximate actual values better than models with any additional second-order terms.

Electrochemical Salt Wasteform Development: A Review of Salt Treatment and Immobilization Options

“…The next step after the salt has been dehalogenated is the consolidation of the salt-occluded zeolite in a wasteform. This has been evaluated using a few different techniques, including in a glass-bonded ceramic using a low-temperature glass developed for this purpose or simply cold pressing the zeolite and heat treating the pellet into a dense monolith …”

Identification of Potential Waste Processing and Waste Form Options for Molten Salt Reactors

“…This results in a salt-occluded zeolite (SOZ) containing the other salt cations, which decomposes at around 650°C. The SOZ product can be (1) encapsulated in a lowmelting glass such as a bismuth silicate glass (Gardner et al, 2018), or (2) destroyed through incorporation into a glass binder that melts at T > 650°C [e.g., a high-SiO 2 binder like NBS-1, NBS-4, or P57 (Riley et al, 2017d;Vienna et al, 1998)]. Alternatively, it is also possible that this approach could be a viable option for defluorinating fluoride-based salts, although it has not yet been tested for that application.…”