• Applied Chemistry for Engineering
• /
• v.17 no.1
• /
• pp.12-15
• /
• 2006

The purpose of this study was to investigate the effect of reaction conditions, solvents, and surfactants on the average size and size distribution of silica particles in preparing silica fine powders by sodium silicate. Silica fine particles were synthesized by varying kinds of solvents and surfactants using the emulsion method. Span 20, Span 40, Span 60, and Span 80 were used as nonionic surfactants, Dispersing solvents were n-Hexane, n-Heptane, iso-Octane, and n-Decane of the alkane group. In these experiments, it was known that the optimum dispersion stirring time to form the emulsion of the constant size was around 6 min. The mean sizes of silica particles, at a variety of the dispersion stirring speeds, decreased as the dispersion stirring speed increased. Also, in the case of the solvents, the size of the formed silica particles decreased when the molecular weight of the solvent increased. Lastly, in the case of the surfactants, the mean size of silica particles increased as the hydrophobic lipophilic balance (HLB) value of the surfactant decreased.