The elaboration of gels in the system SiO2 – Na2O was realised by destabilization of sols obtained by alkaline attack of a Tunisia sand. The influence of the sol concentration, pH and nature of the destabilization acid on the gelation time was studied. The porous volume and the specific surface of the aerogels, obtained by hypercritical drying, is influenced by the variation of the concentration, pH and aging time of gels.
S. Marzouk, J. Bouaziz, B. Elleuch, M. Fourati
gels, aerogels, specific viscosity, porous volume, specific surface