Temperature dependence of long-term alteration rate for aqueous alteration of P0798 simulated waste glass under smectite forming conditions

Y. Inagaki, T. Saruwatari, K. Idemitsu, T. Arima, A. Shinkai, H. Yoshikawa, M. Yui

Research output: Chapter in Book/Report/Conference proceedingConference contribution

5 Citations (Scopus)

Abstract

Several kinetic models have been proposed to evaluate the aqueous dissolution/ alteration rate of nuclear waste glass for long-term. However, reaction processes controlling the long-term rate are much more subjected to controversy. Temperature dependence of the long-term alteration rate is an essential issue to understand the rate controlling processes. In the present study, the static aqueous alteration tests were performed with a Japanese simulated waste glass P0798 as a function of temperature from 60°C to 120°C, and the temperature dependence of the long-term alteration rate was evaluated to understand the rate controlling processes. The tests were performed in 0.001M NaOH solution to maintain a constant solution pH of around 10 during the test period and to provide smectite forming conditions where smectite forms as the major secondary phase without zeolite formation. From the test results on dissolution of boron, the alteration rate at each temperature was analyzed by use of a water-diffusion model, The water-diffusion model used is based on a simple assumption; the glass alteration is controlled by water diffusion with ion-exchange between water (hydronium ion; H3O +) and soluble elements (B, Na, Li, etc) at the glass surface layer with the apparent diffusion coefficient Di. A good agreement was observed between the model analysis and the test results, and the value of Di was evaluated to be 1.2 × 10-22 m2/s at 60°C to 1.8 × 10-21 m2/s at 120°C. The Arrhenius plot of Di showed a good linearity to give the activation energy of 49 kJ/mol, which value is close to that for the residual dissolution rate of French waste glass (53 kJ/mol) by Gin [1], and is very close to that for ion-exchange in sodium aluminosilicate glass (49 kJ/mol) by McGrail [2]. These results suggest that water diffusion with ion-exchange can be the dominant process controlling the alteration rate under smectite forming conditions. At elevated temperatures (100°C and 120°C), however, the model-predicted boron releases deviated from the experimental data at the later stage beyond 50-80 days, which suggests that the alteration layer developing at the glass surface may evolve to be protective against the water diffusion to depress the alteration rate as the alteration proceeds.

Original languageEnglish
Title of host publication29th International Symposium on the Scientific Basis for Nuclear Waste Management XXIX
Pages321-328
Number of pages8
Publication statusPublished - Jul 24 2006
Event29th International Symposium on the Scientific Basis for Nuclear Waste Management XXIX - Ghent, Belgium
Duration: Sep 12 2005Sep 16 2005

Publication series

NameMaterials Research Society Symposium Proceedings
Volume932
ISSN (Print)0272-9172

Other

Other29th International Symposium on the Scientific Basis for Nuclear Waste Management XXIX
CountryBelgium
CityGhent
Period9/12/059/16/05

Fingerprint

montmorillonite
Glass
temperature dependence
glass
Water
Ion exchange
Dissolution
Boron
Temperature
water
dissolving
Radioactive Waste
Zeolites
Arrhenius plots
boron
Aluminosilicates
Radioactive wastes
Smectite
hydronium ions
ions

All Science Journal Classification (ASJC) codes

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

Cite this

Inagaki, Y., Saruwatari, T., Idemitsu, K., Arima, T., Shinkai, A., Yoshikawa, H., & Yui, M. (2006). Temperature dependence of long-term alteration rate for aqueous alteration of P0798 simulated waste glass under smectite forming conditions. In 29th International Symposium on the Scientific Basis for Nuclear Waste Management XXIX (pp. 321-328). (Materials Research Society Symposium Proceedings; Vol. 932).

Temperature dependence of long-term alteration rate for aqueous alteration of P0798 simulated waste glass under smectite forming conditions. / Inagaki, Y.; Saruwatari, T.; Idemitsu, K.; Arima, T.; Shinkai, A.; Yoshikawa, H.; Yui, M.

29th International Symposium on the Scientific Basis for Nuclear Waste Management XXIX. 2006. p. 321-328 (Materials Research Society Symposium Proceedings; Vol. 932).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Inagaki, Y, Saruwatari, T, Idemitsu, K, Arima, T, Shinkai, A, Yoshikawa, H & Yui, M 2006, Temperature dependence of long-term alteration rate for aqueous alteration of P0798 simulated waste glass under smectite forming conditions. in 29th International Symposium on the Scientific Basis for Nuclear Waste Management XXIX. Materials Research Society Symposium Proceedings, vol. 932, pp. 321-328, 29th International Symposium on the Scientific Basis for Nuclear Waste Management XXIX, Ghent, Belgium, 9/12/05.
Inagaki Y, Saruwatari T, Idemitsu K, Arima T, Shinkai A, Yoshikawa H et al. Temperature dependence of long-term alteration rate for aqueous alteration of P0798 simulated waste glass under smectite forming conditions. In 29th International Symposium on the Scientific Basis for Nuclear Waste Management XXIX. 2006. p. 321-328. (Materials Research Society Symposium Proceedings).
Inagaki, Y. ; Saruwatari, T. ; Idemitsu, K. ; Arima, T. ; Shinkai, A. ; Yoshikawa, H. ; Yui, M. / Temperature dependence of long-term alteration rate for aqueous alteration of P0798 simulated waste glass under smectite forming conditions. 29th International Symposium on the Scientific Basis for Nuclear Waste Management XXIX. 2006. pp. 321-328 (Materials Research Society Symposium Proceedings).
@inproceedings{56f5b97f8f2d4cbdaccbe81f8f2d97f5,
title = "Temperature dependence of long-term alteration rate for aqueous alteration of P0798 simulated waste glass under smectite forming conditions",
abstract = "Several kinetic models have been proposed to evaluate the aqueous dissolution/ alteration rate of nuclear waste glass for long-term. However, reaction processes controlling the long-term rate are much more subjected to controversy. Temperature dependence of the long-term alteration rate is an essential issue to understand the rate controlling processes. In the present study, the static aqueous alteration tests were performed with a Japanese simulated waste glass P0798 as a function of temperature from 60°C to 120°C, and the temperature dependence of the long-term alteration rate was evaluated to understand the rate controlling processes. The tests were performed in 0.001M NaOH solution to maintain a constant solution pH of around 10 during the test period and to provide smectite forming conditions where smectite forms as the major secondary phase without zeolite formation. From the test results on dissolution of boron, the alteration rate at each temperature was analyzed by use of a water-diffusion model, The water-diffusion model used is based on a simple assumption; the glass alteration is controlled by water diffusion with ion-exchange between water (hydronium ion; H3O +) and soluble elements (B, Na, Li, etc) at the glass surface layer with the apparent diffusion coefficient Di. A good agreement was observed between the model analysis and the test results, and the value of Di was evaluated to be 1.2 × 10-22 m2/s at 60°C to 1.8 × 10-21 m2/s at 120°C. The Arrhenius plot of Di showed a good linearity to give the activation energy of 49 kJ/mol, which value is close to that for the residual dissolution rate of French waste glass (53 kJ/mol) by Gin [1], and is very close to that for ion-exchange in sodium aluminosilicate glass (49 kJ/mol) by McGrail [2]. These results suggest that water diffusion with ion-exchange can be the dominant process controlling the alteration rate under smectite forming conditions. At elevated temperatures (100°C and 120°C), however, the model-predicted boron releases deviated from the experimental data at the later stage beyond 50-80 days, which suggests that the alteration layer developing at the glass surface may evolve to be protective against the water diffusion to depress the alteration rate as the alteration proceeds.",
author = "Y. Inagaki and T. Saruwatari and K. Idemitsu and T. Arima and A. Shinkai and H. Yoshikawa and M. Yui",
year = "2006",
month = "7",
day = "24",
language = "English",
isbn = "1558998896",
series = "Materials Research Society Symposium Proceedings",
pages = "321--328",
booktitle = "29th International Symposium on the Scientific Basis for Nuclear Waste Management XXIX",

}

TY - GEN

T1 - Temperature dependence of long-term alteration rate for aqueous alteration of P0798 simulated waste glass under smectite forming conditions

AU - Inagaki, Y.

AU - Saruwatari, T.

AU - Idemitsu, K.

AU - Arima, T.

AU - Shinkai, A.

AU - Yoshikawa, H.

AU - Yui, M.

PY - 2006/7/24

Y1 - 2006/7/24

N2 - Several kinetic models have been proposed to evaluate the aqueous dissolution/ alteration rate of nuclear waste glass for long-term. However, reaction processes controlling the long-term rate are much more subjected to controversy. Temperature dependence of the long-term alteration rate is an essential issue to understand the rate controlling processes. In the present study, the static aqueous alteration tests were performed with a Japanese simulated waste glass P0798 as a function of temperature from 60°C to 120°C, and the temperature dependence of the long-term alteration rate was evaluated to understand the rate controlling processes. The tests were performed in 0.001M NaOH solution to maintain a constant solution pH of around 10 during the test period and to provide smectite forming conditions where smectite forms as the major secondary phase without zeolite formation. From the test results on dissolution of boron, the alteration rate at each temperature was analyzed by use of a water-diffusion model, The water-diffusion model used is based on a simple assumption; the glass alteration is controlled by water diffusion with ion-exchange between water (hydronium ion; H3O +) and soluble elements (B, Na, Li, etc) at the glass surface layer with the apparent diffusion coefficient Di. A good agreement was observed between the model analysis and the test results, and the value of Di was evaluated to be 1.2 × 10-22 m2/s at 60°C to 1.8 × 10-21 m2/s at 120°C. The Arrhenius plot of Di showed a good linearity to give the activation energy of 49 kJ/mol, which value is close to that for the residual dissolution rate of French waste glass (53 kJ/mol) by Gin [1], and is very close to that for ion-exchange in sodium aluminosilicate glass (49 kJ/mol) by McGrail [2]. These results suggest that water diffusion with ion-exchange can be the dominant process controlling the alteration rate under smectite forming conditions. At elevated temperatures (100°C and 120°C), however, the model-predicted boron releases deviated from the experimental data at the later stage beyond 50-80 days, which suggests that the alteration layer developing at the glass surface may evolve to be protective against the water diffusion to depress the alteration rate as the alteration proceeds.

AB - Several kinetic models have been proposed to evaluate the aqueous dissolution/ alteration rate of nuclear waste glass for long-term. However, reaction processes controlling the long-term rate are much more subjected to controversy. Temperature dependence of the long-term alteration rate is an essential issue to understand the rate controlling processes. In the present study, the static aqueous alteration tests were performed with a Japanese simulated waste glass P0798 as a function of temperature from 60°C to 120°C, and the temperature dependence of the long-term alteration rate was evaluated to understand the rate controlling processes. The tests were performed in 0.001M NaOH solution to maintain a constant solution pH of around 10 during the test period and to provide smectite forming conditions where smectite forms as the major secondary phase without zeolite formation. From the test results on dissolution of boron, the alteration rate at each temperature was analyzed by use of a water-diffusion model, The water-diffusion model used is based on a simple assumption; the glass alteration is controlled by water diffusion with ion-exchange between water (hydronium ion; H3O +) and soluble elements (B, Na, Li, etc) at the glass surface layer with the apparent diffusion coefficient Di. A good agreement was observed between the model analysis and the test results, and the value of Di was evaluated to be 1.2 × 10-22 m2/s at 60°C to 1.8 × 10-21 m2/s at 120°C. The Arrhenius plot of Di showed a good linearity to give the activation energy of 49 kJ/mol, which value is close to that for the residual dissolution rate of French waste glass (53 kJ/mol) by Gin [1], and is very close to that for ion-exchange in sodium aluminosilicate glass (49 kJ/mol) by McGrail [2]. These results suggest that water diffusion with ion-exchange can be the dominant process controlling the alteration rate under smectite forming conditions. At elevated temperatures (100°C and 120°C), however, the model-predicted boron releases deviated from the experimental data at the later stage beyond 50-80 days, which suggests that the alteration layer developing at the glass surface may evolve to be protective against the water diffusion to depress the alteration rate as the alteration proceeds.

UR - http://www.scopus.com/inward/record.url?scp=33746034578&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33746034578&partnerID=8YFLogxK

M3 - Conference contribution

AN - SCOPUS:33746034578

SN - 1558998896

SN - 9781558998896

T3 - Materials Research Society Symposium Proceedings

SP - 321

EP - 328

BT - 29th International Symposium on the Scientific Basis for Nuclear Waste Management XXIX

ER -