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The importance of secondary phases in glass corrosion

Description: The analytical expression used to model glass reaction in computer simulations such as EQ6 is compared to experiments used to support the simulations. The expression correctly predicts the acceleration observed in experiments performed at high glass surface area/leachant volume ratios (SA/V) upon the formation of secondary phases. High resolution microscopal analysis of reacted glass samples suggests that the accelerated nature of the reaction after secondary phase formation is due to changes i… more
Date: December 31, 1990
Creator: Ebert, W.L. & Bates, J.K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The reaction of synthetic nuclear waste glass in steam and hydrothermal solution

Description: Glass monoliths of the WVCM 44, WVCM 50, SRL 165, and SRL 202 compositions were reacted in steam and in hydrothermal liquid at 200{degree}C. The glass reaction resulted in the formation of leached surface layers in both environments. The reaction in steam proceeds at a very low rate until precipitates form, after which the glass reaction proceeds at a greater rate. Precipitates were formed on all glass types reacted in steam. The assemblage of phases formed was unique to each glass type, but se… more
Date: December 31, 1989
Creator: Ebert, W.L. & Bates, J.K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Laboratory testing of West Valley reference 6 glass

Description: A series of laboratory tests is being conducted to characterize the corrosion of West Valley reference 6 glass (WV6) and to provide parametric values for modeling its long-term durability. Models require measurement of the corrosion rate in the absence of corrosion products and in fluids that are {open_quotes}saturated{close_quotes} with corrosion products, and the identification of alteration phases. Corrosion rates in dilute and saturated conditions were measured using MCC-1 and PCT tests, re… more
Date: July 1, 1995
Creator: Ebert, W.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Round-robin testing of a standard material for acceptance testing of low-activity radioactive waste products.

Description: A round robin test program was conducted with a glass that was developed for use as a standard test material for acceptance testing of low-activity waste glasses made with Hanford tank wastes. The program was conducted to measure the between-laboratory reproducibility of composition analysis and durability test results. Participants were free to select the methods used to analyze the glass composition. The durability tests closely followed the Product Consistency Test (PCT) Method A, except tha… more
Date: May 13, 1999
Creator: Ebert, W. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Dissolution test for low-activity waste product acceptance.

Description: We have measured the mean and standard deviation of the solution concentrations of B, Na, and Si attained in replicate dissolution tests conducted at temperatures of 20, 40, and 70 C, for durations of 3 and 7 days, and at glass/water mass ratios of 1:10 and 1:1. These and other tests were conducted to evaluate the adequacy of the test methods specified in privatization contracts and to develop a data base that can be used to evaluate the reliability of reported results for tests performed on th… more
Date: May 20, 1998
Creator: Ebert, W. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The effects of the glass surface area/solution volume ratio on glass corrosion: A critical review

Description: This report reviews and summarizes the present state of knowledge regarding the effects of the glass surface area/solution volume (SA/V) ratio on the corrosion behavior of borosilicate waste glasses. The SA/V ratio affects the rate of glass corrosion through the extent of dilution of corrosion products released from the glass into the leachate solution: glass corrosion products are diluted more in tests conducted at low SA/V ratios than they are in tests conducted at high SA/V ratios. Differenc… more
Date: March 1, 1995
Creator: Ebert, W.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Evaluation of a standard test method and material for low-activity waste product acceptance.

Description: The dissolution behavior of a candidate reference glass has been measured under a range of test conditions. The data base from these tests can be used to evaluate the credibility and validity of test results reported by Private Contractors as part of the acceptance process for immobilized low-activity waste (ILAW) products for DOE wastes. The LRM-1 glass that was used in the tests was formulated to be compositionally representative of anticipated ILAW products for Hanford and other Department o… more
Date: January 29, 1998
Creator: Ebert, W. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Interlaboratory Study of the Reproducibility of the Single-Pass Flow-Through Test Method : Measuring the Dissolution Rate of Lrm Glass at 70 {Sup {Degree}}C and PH 10.

Description: An international interlaboratory study (ILS) was conducted to evaluate the precision with which single-pass flow-through (SPFT) tests can be conducted by following a method to be standardized by the American Society for Testing and Materials - International. Tests for the ILS were conducted with the low-activity reference material (LRM) glass developed previously for use as a glass test standard. Tests were conducted at 70 {+-} 2 C using a LiCl/LiOH solution as the leachant to impose an initial… more
Date: February 28, 2006
Creator: Ebert, W. L. & Engineering, Chemical
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Vapor hydration and subsequent leaching of transuranic-containing SRL and WV glasses

Description: Prior to contact by liquid water and subsequent leaching, high-level nuclear waste glass subject to disposal in the unsaturated environment at Yucca Mountain, Nevada, will be altered through contact with humid air. Conditions could range from temperatures as high as 200{degree}C to ambient repository temperature after cooling and relative humidities up to 100% depending on the air flow and heat transport dynamics of the waste package and near field environments. However, under any potential set… more
Date: September 1, 1989
Creator: Bates, J.K.; Ebert, W.L. & Gerding, T.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

A comparison of glass reaction at high and low SA/V: PCT vs MCC-1

Description: Leach tests have been performed at surface area/volume (SA/V) of 10, 2000, and 20,000 m{sup {minus}1} using actinide-doped borosilicate waste glass (SRL 131 and SRL 202) to assess the effects of the SA/V on the mechanism and rate of the glass reaction. Solution results are presented which show the major effect of the SA/V to be dilution. Higher SA/V result in higher leachate pH values being attained due to initial ion exchange reactions. The higher pH values then accelerate hydrolysis of the gl… more
Date: January 1, 1992
Creator: Ebert, W.L. & Bates, J.K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

A comparison of glass reaction at high and low SA/V: PCT vs MCC-1

Description: Leach tests have been performed at surface area/volume (SA/V) of 10, 2000, and 20,000 m{sup {minus}1} using actinide-doped borosilicate waste glass (SRL 131 and SRL 202) to assess the effects of the SA/V on the mechanism and rate of the glass reaction. Solution results are presented which show the major effect of the SA/V to be dilution. Higher SA/V result in higher leachate pH values being attained due to initial ion exchange reactions. The higher pH values then accelerate hydrolysis of the gl… more
Date: April 1, 1992
Creator: Ebert, W. L. & Bates, J. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

The corrosion behavior of DWPF glasses

Description: The authors analyzed the corroded surfaces of reference glasses developed for the Defense Waste Processing Facility (DWPF) to characterize their corrosion behavior. The corrosion mechanism of nuclear waste glasses must be known in order to provide source terms describing radionuclide release for performance assessment calculations. Different DWPF reference glasses were corroded under conditions that highlighted various aspects of the corrosion process and led to different extents of corrosion. … more
Date: June 1, 1995
Creator: Ebert, W.L. & Bates, J.K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Performance testing of West Valley Reference 6 glass

Description: The chemical durability of West Valley Reference 6 glass is being evaluated by using a suite of laboratory tests which highlight the early, interim, and long-term stages of corrosion. The test results are being used to describe the glass corrosion path and its long-term durability. The long-term durability of the SRL Environmental Assessment glass is being evaluated for comparison. Test results also provide parameter values for an analytical corrosion model that can be used in performance asses… more
Date: June 1, 1995
Creator: Ebert, W.L. & Bates, J.K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Glass dissolution rates from static and flow-through tests.

Description: We measured the dissolution rate of a simple five-component glass at 70 C using static tests and single-pass flowthrough (SPFT) tests with pH buffers at pH values of 6.2, 8.3, and 9.6. The two methods yielded similar rates; however, the measured rates are about 10X higher than the rates measured previously for a glass having the same composition using an SPFT test method. Differences are attributed to how the effect of the solution flow rate on the glass dissolution rate was taken into account … more
Date: May 24, 2002
Creator: Jeong, S.-Y. & Ebert, W. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Examination of subaerially altered basaltic glass with TEM and EELS

Description: We have examined the weathered surfaces of 720 year old Hawaiian basalt glasses that were recovered from a subaerial environment with high-resolution transmission electron microscopy (TEM) and energy filtered imaging and electron energy loss spectroscopy (EELS) techniques. Whereas the alteration products (palagonite) were physically detached from the underlying glass in most samples, a gel-like amorphous layer was observed adjacent to the glass in a few samples. To our knowledge, this is the fi… more
Date: June 17, 1998
Creator: Luo, J. S. & Ebert, W. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Comparison of the corrosion behaviors of the glass-bonded sodalite ceramic waste form and reference HLW glasses.

Description: A glass-bonded sodalite ceramic waste form is being developed for the long-term immobilization of salt wastes that are generated during spent nuclear fuel conditioning activities. A durable waste form is prepared by hot isostatic pressing (HIP) a mixture of salt-loaded zeolite powders and glass frit. A mechanistic description of the corrosion processes is being developed to support qualification of the CWF for disposal. The initial set of characterization tests included two standard tests that … more
Date: May 6, 1999
Creator: Ebert, W. L. & Lewis, M. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Laboratory testing of waste glass aqueous corrosion; effects of experimental parameters

Description: A literature survey has been performed to assess the effects of the temperature, glass surface area/leachate volume ratio, leachant composition, leachant flow rate, and glass composition (actual radioactive vs. simulated glass) used in laboratory tests on the measured glass reaction rate. The effects of these parameters must be accounted for in mechanistic models used to project glass durability over long times. Test parameters can also be utilized to highlight particular processes in laborator… more
Date: December 31, 1993
Creator: Ebert, W. L. & Mazer, J. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Round-robin testing of a reference glass for low-activity waste forms

Description: A round robin test program was conducted with a glass that was developed for use as a standard test material for acceptance testing of low-activity waste glasses made with Hanford tank wastes. The glass is referred to as the low-activity test reference material (LRM). The program was conducted to measure the interlaboratory reproducibility of composition analysis and durability test results. Participants were allowed to select the methods used to analyze the glass composition. The durability te… more
Date: December 6, 1999
Creator: Ebert, W. L. & Wolf, S. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Microstructural characterization of halite inclusion in a glass-bonded ceramic waste form.

Description: A glass-bonded ceramic waste form is being developed to immobilize radioactively contaminated chloride waste salts generated during the conditioning of spent sodium-bonded nuclear fuel for disposal. The waste salt is first mixed with zeolite A to occlude the salt into cavities in the zeolite structure. The salt-loaded zeolite is then mixed with a borosilicate glass and consolidated by hot isostatic pressing. During this process, the zeolite converts to the mineral sodalite, which retains most o… more
Date: December 14, 2000
Creator: Luo, J. S. & Ebert, W. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Comparison of the results of short-term static tests and single-pass flow-through tests with LRM glass.

Description: Static dissolution tests were conducted to measure the forward dissolution rate of LRM glass at 70 C and pH(RT) 11.7 {+-} 0.1 for comparison with the rate measured with single-pass flow-through (SPFT) tests in an interlaboratory study (ILS). The static tests were conducted with monolithic specimens having known geometric surface areas, whereas the SPFT tests were conducted with crushed glass that had an uncertain specific surface area. The error in the specific surface area of the crushed glass… more
Date: January 29, 2007
Creator: Ebert, W. L. & Engineering, Chemical
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Corrosion Testing of a Plutonium-Loaded Lanthanide Borosilicate Glass Made With Frit B.A.

Description: Laboratory tests were conducted with a lanthanide borosilicate (LaBS) glass made with Frit B and added PuO2 (the glass is referred to herein as Pu LaBS-B glass) to measure the dependence of the glass dissolution rate on pH and temperature. These results are compared with the dependencies used in the Defense HLW Glass Degradation Model that was developed to account for HLW glasses in total system performance assessment (TSPA) calculations for the Yucca Mountain repository to determine if that mo… more
Date: September 30, 2006
Creator: Ebert, W. L. & Engineering, Chemical
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Modeling surface area to volume effects on borosilicate glass dissolution

Description: We simulated the reaction of SRL-131 glass with equilibrated J-13 water in order to investigate the effects of surface area to volume ratio (SA/V) on glass dissolution. We show that glass-fluid ion exchange causes solution pH to rise to progressively higher values as SA/V increases. Because the ion exchange is rapid relative to the duration of the glass dissolution experiment, the pH effect does not scale with (SA/V)*time. Experiments compared at the same (SA/V)*time value therefore have differ… more
Date: November 1, 1992
Creator: Bourcier, W. L.; Ebert, W. L. & Feng, X.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Yucca Mountain Project: FY 2006 Annual Report for Waste Form Testing Activities.

Description: This report describes the experimental work performed at Argonne National Laboratory (Argonne) during fiscal year (FY 2006) under the Bechtel SAIC Company, LLC (BSC) Memorandum Purchase Order (MPO) contract number B004210CM3X. Because this experimental work is focused on the dissolution and precipitation behavior of neptunium, the report also includes, or incorporates by reference, earlier results that are relevant to presenting a more complete understanding of the likely behavior of neptunium … more
Date: November 1, 2006
Creator: Ebert, W. L.; Fortner, J. A.; Guelis, A. V. & Cunnane, J. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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