Electrokinetic potential measurements in a system of SiO2-CaCl2-H2O

The aim of the presented work was to study the dependence of the SiO2 sol z eta potential on the contents of calcium chloride. The sol contained 2.27 w t. % of SiO2 and the content of anhydrous CaCl2 varied between 0.126 and 13 .0 wt.%. The experiments demonstrated an influence of calcium and chloride ions on the electrokinetic potential; Formation of gels based on calcium-si licate hydrates can be expected with an increasing content of calcium ions in the solution. an the other hand, increasing content of chloride ions bri ngs about a lowering of rite pH of the solution, thus slowing down the tran sport of the silicate components into the solution. These chloride effects ate more apparent at higher CaCl2 concentrations. The described phenomenon explains the behaviour of calcium chloride as an additive accelerating the hydration of the silicate components of clinker minerals.