Concentration- and pH-dependence of highly alkaline sodium silicate solutions

Jonas Nordström; Erik Nilsson; Patrik Jarvol; Moheb Nayeri; Anders Palmqvist; Johan Bergenholtz; Aleksandar Matic

doi:10.1016/j.jcis.2010.12.085

Concentration- and pH-dependence of highly alkaline sodium silicate solutions

J Colloid Interface Sci. 2011 Apr 1;356(1):37-45. doi: 10.1016/j.jcis.2010.12.085. Epub 2011 Jan 5.

Authors

Jonas Nordström¹, Erik Nilsson, Patrik Jarvol, Moheb Nayeri, Anders Palmqvist, Johan Bergenholtz, Aleksandar Matic

Affiliation

¹ Department of Applied Physics, Chalmers University of Technology, Gothenburg, Sweden.

PMID: 21272893
DOI: 10.1016/j.jcis.2010.12.085

Abstract

In this study two routes for the gelation of water glass have been investigated; the destabilization by a change in pH and by an increase in concentration through evaporation. Both methods produce optically transparent, highly viscous, homogeneous solutions. The structure and dynamics of the solutions along the two routes have been investigated with dynamic light scattering, (29)Si-Nuclear Magnetic Resonance spectroscopy, viscosity measurements and infrared spectroscopy. We find that the two routes are fundamentally different. Increasing the concentration of the sodium silicate system leaves the silica speciation apparently unchanged. Lowering the pH leads to condensation reactions, thus a change in the silica speciation.