The effect of mixed modifiers on nuclear waste glass processing, leaching, and Raman spectra

1998 ◽  
Vol 13 (1) ◽  
pp. 8-15 ◽  
Author(s):  
S. V. Raman
Keyword(s):  
Raman Spectra ◽  
Nuclear Waste ◽  
Initial Increase ◽  
Borosilicate Glasses ◽  
Leach Rate ◽  
Mixed Alkali ◽  
Glass Processing ◽  
Nuclear Waste Glass ◽  
Mixed Alkali Effect ◽  
Waste Loading

Borosilicate glasses with different waste loadings were prepared by ambient melting, quenching, and annealing. Some melt compositions partially crystallize to durable phases of zircon and forsterite. The coexisting liquid quenches to glass and endures the leach tests. The waste loading dependent leach rate trends of these glasses are reminiscent of the mixed alkali effect. Raman spectra suggest initial increase in durability with increases in the depolymerization of silicate species. Fluorine and hydroxyl ions also contribute to depolymerization. Tetraborate and metaborate rings are identified in the Raman spectra. The durability is enhanced when tetraborate bands are more intense than the metaborate bands.

scholarly journals Does Fully Radioactive Glass Behave Differently than Simulated Waste Glass?

1992 ◽  
Vol 294 ◽  
Author(s):  
X. Feng ◽  
J. K. Bates ◽  
C. R. Bradley ◽  
E. C. Buck
Keyword(s):  
Radiation Field ◽  
Nuclear Waste ◽  
Potassium Feldspar ◽  
Waste Glass ◽  
Solution Ph ◽  
Static Tests ◽  
Leach Rate ◽  
Nuclear Waste Glass ◽  
Surface Alteration ◽  
Leach Behavior

ABSTRACTStatic tests at SA/V (ratio of surface area of glass to solution volume) 20,000 m−1 on SRL 200 glass compositions show that, at long test periods, the simulated nuclear waste glass (nonradioactive) leaches faster than the corresponding radioactive glass by a factor of about 40, although comparative tests, done through 560 days, at lower SA/V, 2000 m−1, indicate little difference in the leach behavior of the two types of glasses. The similarity in leach behavior between radioactive and simulated glasses at SAN of 2000 m−1 or lower is also observed for SRL 165/42 and 131/11 compositions. The accelerated glass reaction with the simulated glass 200S is associated with the formation of crystalline phases such as clinoptilolite (or potassium feldspar), and a pH excursion. The radiation field generated by the fully radioactive glass reduces the solution pH. This lower pH, in turn, may retard the onset of increased reaction rate. The radiation field generated by the radioactive glasses does not directly affect the stability of the glass surface alteration layer under those conditions where the radioactive and simulated glasses react at the same rate. These results suggest that the fully radioactive nuclear waste glass 200R may maintain a much lower leach rate than the simulated 200S, if the lower pH in the 200R leachate can be sustained. Meaningful comparison tests between radioactive and simulated nuclear waste glasses should include long-term and high SA/V tests.

Corrigendum to “The dissolution rates of simulated UK Magnox – ThORP blend nuclear waste glass as a function of pH, temperature and waste loading” [Miner. Mag. 79, (2015) 1529–1542]

2018 ◽  
Vol 82 (4) ◽  
pp. 939-942 ◽  
Author(s):  
Claire. L. Corkhill ◽  
Adam J. Fisher ◽  
Denis M. Strachan ◽  
Russell J. Hand ◽  
Neil C. Hyatt
Keyword(s):  
Nuclear Waste ◽  
Intrinsic Rate ◽  
Data Fitting ◽  
Waste Glass ◽  
Dissolution Rates ◽  
Nuclear Waste Glass ◽  
Corrected Data ◽  
Waste Loading ◽  
Fitting In ◽  
Intrinsic Rate Constant

AbstractWe revise the data fitting in our original paper [The dissolution rates of simulated UK Magnox - ThORP blend nuclear waste glass as a function of pH, temperature and waste loading, Miner. Mag.79 (2015) 1529–1542]. The intrinsic rate constant data were calculated incorrectly, the corrected data are presented herein. To support the corrected analysis we have also taken the opportunity to report some additional 90°C data. The conclusions of the original paper remain sound.

Composition-Structure Relationships in Simplified Nuclear Waste Glasses: 1. Mixed Alkali Borosilicate Glasses

2010 ◽  
Vol 94 (1) ◽  
pp. 151-159 ◽  
Author(s):  
Andrew J. Connelly ◽  
Karl P. Travis ◽  
Russell J. Hand ◽  
Neil C. Hyatt ◽  
Ewan Maddrell
Keyword(s):  
Nuclear Waste ◽  
Borosilicate Glasses ◽  
Mixed Alkali ◽  
Composition Structure ◽  
Alkali Borosilicate Glasses

Role of Surface Layers in the Leaching Behavior of Glass

1988 ◽  
Vol 125 ◽  
Author(s):  
B.K. Zoitos ◽  
D.E. Clark
Keyword(s):  
Surface Layer ◽  
Nuclear Waste ◽  
Surface Composition ◽  
Analytical Techniques ◽  
Surface Layers ◽  
Leaching Behavior ◽  
Leach Rate ◽  
Layer Analysis ◽  
Nuclear Waste Glass

ABSTRACTResults are presented from a two-year dynamic leach test of nuclear waste glass under conditions designed to simulate those of the Stripa granite repository. Solution and surface analytical techniques were used to assess the glass leach rate as well as surface composition and morphology. Glass leach rates were observed to decrease by a factor of two during the first six months. This effect is attributed to the formation of a protective surface layer. Analysis of this layer shows it to be rich in silicon and iron and depleted in lithium, sodium and boron. It was also found that the layer is subject to dissolution.

The dissolution of simulant UK Ca/Zn-modified nuclear waste glass: the effect of increased waste loading

MRS Advances ◽  
2021 ◽  
Author(s):  
Adam J. Fisher ◽  
Mike T. Harrison ◽  
Neil C. Hyatt ◽  
Russell J. Hand ◽  
Claire L. Corkhill
Keyword(s):  
Nuclear Waste ◽  
Waste Glass ◽  
Nuclear Waste Glass ◽  
Waste Loading

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

Materials ◽  
2019 ◽  
Vol 12 (9) ◽  
pp. 1462 ◽  
Author(s):  
Osama Farid ◽  
Michael Ojovan ◽  
A. Massoud ◽  
R.O. Abdel Rahman
Keyword(s):  
Nuclear Waste ◽  
Temporal Change ◽  
Matrix Composition ◽  
Dissolution Process ◽  
Borosilicate Glasses ◽  
Leaching Characteristics ◽  
Waste Loading ◽  
Thermodynamic Instability ◽  
Fractional Release ◽  
Alkali Borosilicate Glasses

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.

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