Borosilicate Nuclear Waste Glass Alteration Kinetics: Chemical Inhibition and Affinity Control

Abstract

The objective of this work was to develop a more representative mathematical formulation of the alteration kinetics of the borosilicate SON68 glass by combining three approaches: (1) Compare extensive prior experimental static leaching results for SON68 glass with the first-order kinetic law in which silica is the predominant element, (2) Assess the exact role of dissolved silica on the alteration rate under conditions near and far from saturation, by means of dynamic leach tests and, (3) Compare the new data with the general kinetic law for silicates in which the reaction affinity, catalysis and inhibition are the three influencing factors.

Development and evaluation of a thermodynamic dataset for phases of interest in CO2 mineral sequestration in basaltic rocks

“…This method of estimating solubility products of borosilicate and aluminosilicate glasses has already been successfully applied by e.g. Bourcier et al (1992), Advocat et al (1998) and Leturcq et al (1999). Techer et al (2001) also obtained a good result using the same approach to model the dissolution of synthetic basaltic glass at 90°C.…”

The dissolution rates of natural glasses as a function of their composition at pH 4 and 10.6, and temperatures from 25 to 74°C

“…Ewing and Haaker, 1979;Byers et al, 1985;Lutze et al, 1985). To model the long-term behaviour and stability of this radioactive waste confinement host studies have concentrated on laboratory corroded basaltic and synthetic borosilicate glasses and naturally altered basaltic glasses (Furnes, 1975(Furnes, , 1978Seyfried Jr. and Bischoff, 1979;Allen, 1982;Malow et al, 1984;Crovisier et al, 1983Crovisier et al, , 1985Crovisier et al, , 1987Crovisier et al, , 1989aCrovisier et al, , 1989bGrambow, 1985;Grambow et al, 1985;Berger et al, 1987Berger et al, , 1988Berger et al, , 1994Gislason and Eugster, 1987a;Eggleton et al, 1987;Guy and Schott, 1989;Murukami et al, 1989;Jercinovic et al, 1990aJercinovic et al, , 1990bAdvocat et al, 1990Advocat et al, , 1991Advocat et al, , 1998Nesbitt and Wilson, 1992;Ghiara et al, 1993;Gislason et al, 1993;Morgenstein and Shettel, 1994;Daux et al, 1994Daux et al, , 1997Leturcq et al, 1999;Abraitis et al, 2000;Techer et al, 2001). Most of the natural glass dissolution studies were performed in either high ionic strength/seawater solutions or at high temperatures, and many were carried out in closed system batch reactors.…”

Modelling the alteration gel composition of simplified borosilicate glasses by precipitation of an ideal solid solution in equilibrium with the leachant

“…(1) by including other elements in the affinity calculations, such as Al or Fe [38][39][40]. Besides, the attempts to use the overall chemical affinity of the glass with respect to water as affinity control failed [35,[41][42][43]. Other refinements have been considered, such as the reduction of the initial dissolution rate by an inhibiting effect of the orthosilicic acid on glass dissolution [35,42,44].…”

“…Besides, the attempts to use the overall chemical affinity of the glass with respect to water as affinity control failed [35,[41][42][43]. Other refinements have been considered, such as the reduction of the initial dissolution rate by an inhibiting effect of the orthosilicic acid on glass dissolution [35,42,44]. Thus, Bourcier et al [45] have proposed a model, in which the dissolution rate depends on the affinity between the alteration gel, regarded as an ideal solid solution, and the solution rather than on the affinity between the glass and the solution.…”