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Title: Accelerated Leach Testing of GLASS (ALTGLASS): I. Informatics approach to high level waste glass gel formation and aging

Abstract

Glass corrosion data from the ALTGLASS™ database were used to determine if gel compositions, which evolve as glass systems corrode, are correlated with the generation of zeolites and subsequent increase in the glass dissolution rate at long times. The gel compositions were estimated based on the difference between the elemental glass starting compositions and the measured elemental leachate concentrations from the long-term product consistency tests (ASTM C1285) at various stages of dissolution, ie, reaction progress. A well-characterized subset of high level waste glasses from the database was selected: these glasses had been leached for 15-20 years at reaction progresses up to ~80%. The gel composition data, at various reaction progresses, were subjected to a step-wise regression, which demonstrated that hydrogel compositions with Si*/Al* ratios of <1.0 did not generate zeolites and maintained low dissolution rates for the duration of the experiments. Glasses that formed hydrogel compositions with Si^*/Al^* ratios ≥1, generated zeolites accompanied by a resumption in the glass dissolution rate. Finally, the role of the gel Si/Al ratio, and the interactions with the leachate, provides the fundamental understanding needed to predict if and when the glass dissolution rate will increase due to zeolitization.

Authors:
 [1];  [1];  [1];  [1];  [1]
  1. Savannah River National Lab., Aiken, SC (United States)
Publication Date:
Research Org.:
Savannah River Site (SRS), Aiken, SC (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1372631
Report Number(s):
SRNL-STI-2014-00274
Journal ID: ISSN 2041-1286
Grant/Contract Number:
AC09-08SR22470
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
International Journal of Applied Glass Science
Additional Journal Information:
Journal Volume: 8; Journal Issue: 1; Journal ID: ISSN 2041-1286
Publisher:
American Ceramic Society
Country of Publication:
United States
Language:
English
Subject:
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES; 36 MATERIALS SCIENCE; corrosion; glass durability; glass leaching; modeling; nuclear waste

Citation Formats

Jantzen, Carol M., Trivelpiece, Cory L., Crawford, Charles L., Pareizs, John M., and Pickett, John B. Accelerated Leach Testing of GLASS (ALTGLASS): I. Informatics approach to high level waste glass gel formation and aging. United States: N. p., 2017. Web. doi:10.1111/ijag.12262.
Jantzen, Carol M., Trivelpiece, Cory L., Crawford, Charles L., Pareizs, John M., & Pickett, John B. Accelerated Leach Testing of GLASS (ALTGLASS): I. Informatics approach to high level waste glass gel formation and aging. United States. doi:10.1111/ijag.12262.
Jantzen, Carol M., Trivelpiece, Cory L., Crawford, Charles L., Pareizs, John M., and Pickett, John B. Sat . "Accelerated Leach Testing of GLASS (ALTGLASS): I. Informatics approach to high level waste glass gel formation and aging". United States. doi:10.1111/ijag.12262. https://www.osti.gov/servlets/purl/1372631.
@article{osti_1372631,
title = {Accelerated Leach Testing of GLASS (ALTGLASS): I. Informatics approach to high level waste glass gel formation and aging},
author = {Jantzen, Carol M. and Trivelpiece, Cory L. and Crawford, Charles L. and Pareizs, John M. and Pickett, John B.},
abstractNote = {Glass corrosion data from the ALTGLASS™ database were used to determine if gel compositions, which evolve as glass systems corrode, are correlated with the generation of zeolites and subsequent increase in the glass dissolution rate at long times. The gel compositions were estimated based on the difference between the elemental glass starting compositions and the measured elemental leachate concentrations from the long-term product consistency tests (ASTM C1285) at various stages of dissolution, ie, reaction progress. A well-characterized subset of high level waste glasses from the database was selected: these glasses had been leached for 15-20 years at reaction progresses up to ~80%. The gel composition data, at various reaction progresses, were subjected to a step-wise regression, which demonstrated that hydrogel compositions with Si*/Al* ratios of <1.0 did not generate zeolites and maintained low dissolution rates for the duration of the experiments. Glasses that formed hydrogel compositions with Si^*/Al^* ratios ≥1, generated zeolites accompanied by a resumption in the glass dissolution rate. Finally, the role of the gel Si/Al ratio, and the interactions with the leachate, provides the fundamental understanding needed to predict if and when the glass dissolution rate will increase due to zeolitization.},
doi = {10.1111/ijag.12262},
journal = {International Journal of Applied Glass Science},
number = 1,
volume = 8,
place = {United States},
year = {Sat Feb 18 00:00:00 EST 2017},
month = {Sat Feb 18 00:00:00 EST 2017}
}

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