Single-pass flow-through experiments on a simulated waste glass in alkaline media at 40°C.: II. Experiments conducted with buffer solutions containing controlled quantities of Si and Al

Additional single-pass flow-through (SPFT) experiments have been conducted with a complex, simulated waste glass at 40°C in moderately alkaline media. Results are compared to those obtained in the experiments described in Part I, and with published data obtained in long-term, static, batch dissolution experiments with this glass formulation. Dissolution rate laws for the glass must account for the rate influencing effects of both dissolved Si and Al species. These experiments have shown that on a mole per mole basis, dissolved Al has a more significant influence on the glass dissolution rate than dissolved Si under these experimental conditions. The very low ‘long-term’ dissolution rates reported in static batch dissolution experiments reflect near saturation conditions that are not attained in SPFT tests as a result of solution flow-through.