Thermodynamic stability of waste glasses compared to leaching behaviour

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

“…Since SiO 2 is by far the most important glass oxide in natural glasses, Jantzen and Plodinec (1984) effectively found that the logarithm of their glass dissolution rates decreased linearly with the Si content. Perret et al (2003) reached a similar conclusion in their investigation on the thermodynamic stability of waste glasses. They demonstrated that Si and Ca contents control the glass' thermodynamic stability; the latter element indirectly by governing the pH during corrosion experiments whereas silicon directly influences the glass durability.…”

Time resolved alteration process of oxide glasses

“…As the alteration is performed in the so-called 'static mode,' the buffer is not renewed during the experiment and each time of alteration requires its own container. Despite the use of a buffer, the pH increased from the initial values (9.2) due to the amount of Na and Br lixiviated after 24 h. The effect of their dissolution on the evolution of alkaline conditions was described and explained elsewhere [14]. Depending of the Zr content, the final values were 9.7 (0% Zr), 10 (1% Zr), 9.9 (2% Zr), 9.6 (4% Zr) and 9.3 (8% Zr).…”

Experimentally determined dissolution kinetics of Na-rich borosilicate glass at far from equilibrium conditions: Implications for Transition State Theory

“…The Free Energy of Hydration (FEH) model, and its variants (Paul, 1977;Plodinec et al, 1984;Jantzen, 1992;Plodinec and Wicks, 1994;Jantzen et al, 1998), have enjoyed widespread attention at National Laboratories tasked with disposition of borosilicate nuclear waste glass. Subsequent investigators (Conradt, 2001;Linard et al, 2001;Perret et al, 2003) have proposed variations and refinements in the algorithm and the popularity of FEH models lie in their ease of use: glass structure does not have to be known in detail, only bulk chemistry.…”