Sodium silicate solutions from dissolution of glasswastes. Statistical analysis

It has studied the solubility process of four different waste glasses (with different particle sizes, 125 µm) in alkaline solutions (NaOH and NaOH/Na₂CO₃) and water as a reference and under different conditions of solubility (at room temperature, at 80°C and a mechano-chemical process). Have established the optimal conditions of solubility and generation of sodium silicates solutions, and these were: the smaller particle size (<45 µm), with NaOH/Na₂CO₃ solution and with temperature during 6 hours of stirring time. The statistical analyses of the results give importance to the studied variables and the interactions. Through ²⁹Si NMR MAS it has confirmed the formation after dissolution processes of monomeric silicate, suitable for use as an activator in the preparation of alkaline cements and concretes.