Sodium silicate solutions from dissolution of glasswastes. Statistical analysis

Abstract

It has studied the solubility process of four different waste glasses (with different particle sizes, <45 μm and>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. Copyright: © 2014 CSIC.