Impact of Crystalline Phases on Low-Activity Waste Glass Durability: Insights from PCT and VHT

Chong, Saehwa; Reiser, Joelle T.; Ferkl, Pavel; Riley, Brian J. (ORCID:0000000277456730); Vienna, John D.; Crum, Jarrod V.; Lu, Xiaonan (ORCID:0000000179708148)

doi:10.1016/j.jnoncrysol.2026.124271

DOE OSTI · 3732645

Impact of Crystalline Phases on Low-Activity Waste Glass Durability: Insights from PCT and VHT

Chong, Saehwa·Reiser, Joelle T.·Ferkl, Pavel·Riley, Brian J. (ORCID:0000000277456730)·Vienna, John D.·Crum, Jarrod V.·Lu, Xiaonan (ORCID:0000000179708148)

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Abstract

During vitrification of nuclear wastes, slow cooling along the container centerline promotes crystalline phase formation, which can alter residual glass composition and reduce chemical durability. This study investigates the effects of crystalline phases on the chemical durability of low-activity waste (LAW) borosilicate glasses using the product consistency test (PCT) and vapor hydration test (VHT) on container centerline cooled (CCC) samples. A preliminary model (R2 = 0.88) was developed to predict CCC PCT responses based on glass composition, PCT data from quenched glasses, and measured crystal fractions. Using the latest LAW glass dataset, the feasibility of predictive modeling is evaluated, limitations in current data and methods are identified, and challenges for improving model accuracy are discussed to guide future data collection and model development.

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Chong, Saehwa, Reiser, Joelle T., Ferkl, Pavel, Riley, Brian J. (ORCID:0000000277456730), Vienna, John D., Crum, Jarrod V., Lu, Xiaonan (ORCID:0000000179708148). 2026-10-01. Impact of Crystalline Phases on Low-Activity Waste Glass Durability: Insights from PCT and VHT. https://doi.org/10.1016/j.jnoncrysol.2026.124271

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