Ion-Exchange Interdiffusion Model with Potential Application to Long-Term Nuclear Waste Glass Performance

2016 ◽  
Vol 120 (17) ◽  
pp. 9374-9384 ◽  
Author(s):  
James Joseph Neeway ◽  
Sebastien N. Kerisit ◽  
Jia Liu ◽  
Jiandong Zhang ◽  
Zihua Zhu ◽  
...  
Keyword(s):  
Ion Exchange ◽  
Nuclear Waste ◽  
Potential Application ◽  
Waste Glass ◽  
Nuclear Waste Glass

Materials Interactions Relating to Long-Term Geologic Disposal of Nuclear Waste Glass

1986 ◽  
Vol 84 ◽  
Author(s):  
Ned E. Bibler ◽  
Carol M. Jantzen
Keyword(s):  
Nuclear Waste ◽  
Review Paper ◽  
Waste Glass ◽  
Waste Form ◽  
Glass Waste ◽  
Waste Package ◽  
Geologic Disposal ◽  
Nuclear Waste Glass ◽  
Backfill Materials

AbstractIn the geologic disposal of nuclear waste glass, the glass will eventually interact with groundwater in the repository system. Interactions can also occur between the glass and other waste package materials that are present. These include the steel canister that holds the glass, the metal overpack over the canister, backfill materials that may be used, and the repository host rock. This review paper systematizes the additional interactions that materials in the waste package will impose on the borosilicate glass waste form-groundwater interactions. The repository geologies reviewed are tuff, salt, basalt, and granite. The interactions emphasized are those appropriate to conditions expected after repository closure, e.g. oxic vs. anoxic conditions. Whenever possible, the effect of radiation from the waste form on the interactions is examined. The interactions are evaluated based on their effect on the release and speciation of various elements including radionuclides from the glass. It is noted when further tests of repository interactions are needed before long-term predictions can be made.

AEM study of reacted surface layer of borosilicate nuclear waste glasses

1992 ◽  
Vol 50 (1) ◽  
pp. 352-353
Author(s):  
L.M. Wang ◽  
S.A. Kaser ◽  
R.C. Ewing ◽  
J.K. Bates
Keyword(s):  
Electron Microscopy ◽  
Surface Layer ◽  
Nuclear Waste ◽  
Reaction Pathway ◽  
Sample Surface ◽  
Carbon Films ◽  
Waste Glass ◽  
Thin Sections ◽  
Nuclear Waste Glass

Analysis of the reacted surface layer of borosilicate glass is important to the understanding of the long term nuclear waste glass reaction process. The objective is to assess the simulated nuclear waste glass/water reaction pathway by identifying new crystalline phases that appear on the glass surfaces during the reaction. The results can be used to validate models generated to predict long-term performance of the nuclear waste glass under a range of conditions.In this study, extensive scanning electron microscopy (SEM) with qualitative energy dispersive x-ray spectroscopy (EDS) analysis, quantitative analytical and high resolution transmission electron microscopy (AEM and HRTEM) have been performed on two 202U glasses which were reacted in saturated water vapor for 14 and 23 days, respectively. In order to study the microchemical and microstructural changes with increasing depth from the reaction surface, TEM specimens were prepared in cross-section using the ultramicrotomy slicing technique similar to that described by Bates et al. In this process, small chunks containing the reacted surface layer and a thin layer of glass were first broken off from the sample surface and each of these chunks was then embedded in resin to form a block. Finally, thin sections, approximately 90 nm thick, were microtomed from these blocks and were transfered to copper mesh grids covered by holey carbon films for observation. AEM and HRTEM analyses were accomplished using a JEOL JEM-2000FX microscope attached with a Noran/TN-5500 EDS system at the University of New Mexico.

Comparison of in Situ and Laboratory Corrosion Experiments with Borosilicate Nuclear Waste Glass

1991 ◽  
Vol 257 ◽  
Author(s):  
Werner Lutze ◽  
Rodney C. Ewing
Keyword(s):  
Nuclear Waste ◽  
Laboratory Data ◽  
Waste Glass ◽  
Simulation Test ◽  
In Situ Tests ◽  
Nuclear Waste Glass ◽  
Systems Simulation ◽  
Long Term Behavior

ABSTRACTThe comparison of laboratory data from the corrosion of borosilicate nuclear waste glass (German SM513LW11 and French R7T7) with data from the Materials Interface Interactions Test (MIIT) and Repository Systems Simulation Test (RSST) illustrates the inherent limitations of in situ tests. Although in situ tests may confirm the short term behavior of waste forms and identify phenomena associated with the repository system, they do not provide the fundamental basis for the extrapolation of long-term behavior.

scholarly journals Pourbaix Diagram for The Prediction of Waste Glass Durability in Geologic Environments

1987 ◽  
Vol 112 ◽  
Author(s):  
Carol M. Jantzen
Keyword(s):  
Nuclear Waste ◽  
Oxidation Potential ◽  
Waste Glass ◽  
Natural Environments ◽  
Long Term Effects ◽  
Pourbaix Diagrams ◽  
Nuclear Waste Glass ◽  
Corrosion Mechanisms ◽  
Different Time Scales

AbstractDissolution of nuclear waste glass occurs by corrosion mechanisms similar to those of metallurgical and mineralogic systems albeit on different time scales. The effects of imposed pH and oxidation potential (Eh) conditions existing in natural environments on metals and minerals have been quantatively and phenomenologically described in compendiums of Pourbaix (pH-potential) diagrams. Construction of Pourbaix diagrams to quantify the response of nuclear waste glasses to repository specific pH and Eh conditions is demonstrated. The expected long-term effects of groundwater contact on the durability of nuclear waste glasses can then be unified.

Effects of Heat Treatment on the Microstructure of a Fully Simulated Nuclear Waste Glass

1990 ◽  
Vol 212 ◽  
Author(s):  
Terese V. Palmiter ◽  
I. Joseph ◽  
L. David Pye
Keyword(s):  
Heat Treatment ◽  
Nuclear Waste ◽  
Scanning Transmission Electron Microscopy ◽  
Waste Glass ◽  
Amorphous Phases ◽  
Transmission Electron ◽  
Heat Treated ◽  
Nuclear Waste Glass ◽  
Scanning Transmission

ABSTRACTSamples of a fully simulated nuclear waste glass under consideration for use in the West Valley Demonstration Project were isothermally heat treated and studied by scanning transmission electron microscopy (STEM). Both fully oxidized and partially reduced specimens were heat treated for 3 hours at 600°C, 700°C, 800°C and 900°C and for 45 days at 10°C above Tg (447°C -461°C) and at 10°C below TB (427°C -441°C). Microstructural features in untreated as well as the heat-treated glasses were studied using STEM. Analysis by energy dispersive spectroscopy (EDS) was used to identify the elemental compositions of the features observed.The predominant crystalline phase present in the samples heat treated for 3 hours was an Fe3O4 type spinel with Ni and Cr substituting for some of the Fe. The spinels varied in size from 0.02 to 10.0 µm, the larger crystals present at higher heat-treatment temperatures. Long term heat treatment above Tg resulted in the formation of small iron-containing crystals ranging in size from 10 to 35 nm. Heat treatment below Tg produced no crystalline or amorphous phases.

Preparation of Hydrated Glass as a Model of Long-Term Leached Nuclear Waste Glass

1994 ◽  
Vol 353 ◽  
Author(s):  
Hiroshi Yamanaka ◽  
Junji Nishii ◽  
Tomoko Akai ◽  
Masaru Yamashita ◽  
Hajimu Wakabayashi
Keyword(s):  
Water Vapor ◽  
Vapor Pressure ◽  
Nuclear Waste ◽  
Depth Profile ◽  
Water Vapor Pressure ◽  
Waste Glass ◽  
Simple Diffusion ◽  
Good State ◽  
Nuclear Waste Glass

AbstractHydrated glass was prepared by the treatment in an autoclave. Specimen in a good state was obtained under unsaturated water vapor pressure conditions. The obtained glass has an silica-rich hydrated layer and proved to be more durable than the original glass. There are some kinds of hydroxyl species in the hydrated glass and there are some patterns in the depth profile of water, indicating that the rate-controlling process is not a simple diffusion and the hydration process is a complicated reaction depending on the conditions. Water in hydrated glass is tightly bonded and a disintegration of hydrated glass in this study occurs at more than 560°C.

Study of crystallization mechanisms in the french nuclear waste glass

1999 ◽  
Vol 556 ◽  
Author(s):  
X. Orlhac ◽  
C. Fillet ◽  
J. Phalippou
Keyword(s):  
Nuclear Waste ◽  
Growth Kinetics ◽  
Growth Curves ◽  
Nucleation And Growth ◽  
Waste Glass ◽  
High Level Waste ◽  
Nucleation Kinetics ◽  
Nuclear Waste Glass ◽  
The Impact

AbstractThe development of glass materials for long-term storage of high-level waste implies determining the glass thermal stability and notably assessing the risk of devitrification. Previous studies of the French nuclear waste glass have identified the crystalline phases and the domains in which they form, and have shown that devitrification is minimal. Modeling the long-term crystallization behavior requires an investigation of the thermodynamic and kinetic mechanisms liable to induce crystallization during cooling. The first step in this approach is to determine the nucleation and growth curves for each of the component phases. Crystals including CaMoO4, CeO2 and ZnCr2O4 were identified in glasses heat-treated at temperatures between 630°C and 1110°C, and the time and thermal dependence of the CaMoO4 morphology were evaluated. The nucleation and growth kinetics of these phases were determined by optical microscopy and SEM, and the impact of impurities was addressed by studying two glasses, with and without platinoid elements. The results indicated enhanced nucleation kinetics in glass containing platinoid elements. No induction time was observed before permanent nucleation in either of the glasses, and rapid saturation of nucleation kinetics—synonymous with the depletion of active centers of nucleation— was detected after a few hours. Furthermore, similar growth kinetics were observed in both glasses. The nucleation and growth curves coincided for all the phases. Peak values were much higher for nucleation than for growth kinetics, confirming the need for a thorough investigation of the mechanisms occurring in and below the glass transition range, i.e. in the non-equilibrium state.

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