Nanosilica-based consolidants distribution in a carbonatic matrix

The aim of the present work is to study the application of four water-based nanosilica dispersions on carbonate rocks in term of penetration depth, particle dimensions, physical-chemical characteristics of dispersions and stone pore radius distribution. In order to have a complete background, a preliminary investigation of untreated Lecce stone and nanosilica dispersions was performed observing different parameters (e.g. porosity, viscosity, surface tension, pH, zeta potential) and TEM observations of dispersions. Different treatments of the Lecce stone were tested and studied by EDX-SEM microscopy. Silicon elemental mapping and distribution profiles were registered on samples cross sections with EDX standardless technique. Based on the obtained results, despite the low viscosity and small dimensions of nanosilica particles, the products seemed unable to deeply penetrate in the porous substrate. However, changes in surface tension of dispersions showed an improvement of the nanodispersions transport inside the stone.