Ceramics-Silikáty 48, (2) 72 - 75 (2004)

A sol of silicon dioxide has been used for modeling of the interactions of calcium salt with SiO₂ - H₂O in high dispersive system. The dependence of the zeta potential on concentration of calcium acetate in SiO₂ - H₂O system has been characterized at lower concentration of acetate by negative values. Isoelectric point has been determined at ratio molar concentration of acetate to silicon dioxide r = c_{calciumacetate}/c_SiO₂ = 0.347. This work is focused on determination of optimum conditions for gelation, control of sol stability and explaining of gelation mechanism by ion exchange on silica surface.