Nuclear waste glass durability. 1; Predicting environmental response from thermodynamic (pourbaix) diagrams

Journal Article · Tue Sep 01 04:00:00 EDT 1992 · Journal of the American Ceramic Society; (United States)

DOI:https://doi.org/10.1111/j.1151-2916.1992.tb05596.x· OSTI ID:7190101

Jantzen, C M ^[1]

---

1. Savannah River Lab., Aiken, SC (United States)

This paper reports that Pourbaix diagrams are shown to conceptually explain dissolution of glasses in terms of their thermodynamic stability and surface layer formation. To predict the long-term effects of ground-water contact on the durability of nuclear waste glass in a geologic repository, the nature of the glass dissolution process has been extensively examined. Hydration thermodynamics has been used to quantify the role of glass composition and the effect of solution pH. The glass compositions examined vary widely in composition and include natural, lunar, medieval, and nuclear waste glasses, as well as some glass-ceramics. The known effects of solution pH and oxidation potential (Eh) on glass dissolution are empirically described by thermodynamically calculated Pourbaix diagrams. Statistical analysis of over 300 glass durability tests demonstrates that the Pourbaix diagram can be quantified because of the colinearity of the hydration free energy with solution pH defined by the Nernst equation and the colinearity of the solution pH with the concentration of dissolved silicon and boron in the solution defined by the pH dependence of the ion activities. Construction of Pourbaix diagrams to describe glass dissolution serves to unify and categorize various existing experimental glass dissolution data.

• DOE Contract Number: AC09-76SR00001
• OSTI ID: 7190101
• Journal Information: Journal of the American Ceramic Society; (United States), Journal Name: Journal of the American Ceramic Society; (United States) Vol. 75:9; ISSN 0002-7820; ISSN JACTAW
• Country of Publication: United States
• Language: English

Related Subjects

052001* -- Nuclear Fuels-- Waste Processing
053002 -- Nuclear Fuels-- Environmental Aspects-- Radioactive Effluents-- (1992-)
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
36 MATERIALS SCIENCE
360604 -- Materials-- Corrosion
Erosion
& Degradation
DIAGRAMS
DISSOLUTION
GLASS
GROUND WATER
HYDROGEN COMPOUNDS
MANAGEMENT
MATERIALS
OXYGEN COMPOUNDS
PHASE DIAGRAMS
PHYSICAL PROPERTIES
PROCESSING
RADIOACTIVE MATERIALS
RADIOACTIVE WASTE MANAGEMENT
RADIOACTIVE WASTE PROCESSING
RADIOACTIVE WASTES
THERMODYNAMIC PROPERTIES
WASTE FORMS
WASTE MANAGEMENT
WASTE PROCESSING
WASTES
WATER