Correlations between synthesis variables and properties of silica precipitates

The influence of twelve synthesis variables upon the properties of the silica precipitates was studied using the Plackett and Burman design. The most important variables controlling the Broensted acidity and the specific surface area were identified. For the syntheses of silica precipitates from sodium silicate in acidic media the initial concentration of sodium silicate solution is the most significant Factor determining the structure and the texture of the porous silica. A method to evaluate the silanol group surface density was also proposed.