Influence of SDS on particle size and adhesion of precipitating calcium carbonate

The effect of different amounts of sodium dodecyl sulfate (SDS) and time of their addition to the system on the properties of calcium carbonate precipitated from aqueous solutions of CaCl2 and Na2CO3 were studied. From statistical evaluation it was found that average number of the particles deposited on glass surface and, average and total surface area they occupy depend on the amount of the surfactant and time of its addition. Only if the surfactant was added to the system just after the CaCl2 and Na2CO3 solutions mixing up, a decrease of these parameters took place, the greatest in the presence of 0.42 μmol of SDS. On the contrary, if SDS solution was added after 3 min, it caused an increase of the average and total surface area occupied by the CaCO3 particles, while the average number of particles changed only within standard deviation. From the obtained results it may be concluded that SDS can affect both nucleation and crystal growth of CaCO3, but its nature depends on the surfactant amount and time of its addition to the system.