Effect of electrolytes and surfactants on physicochemical properties and porous structure of hydrated silicas

Attempts were made to obtain highly dispersed silica from sodium metasilicate solution and carbon dioxide. The aim was to obtain silicas of high or low paraffin oil absorbing capacity. The precipitation process was conducted in a reactor with constant mixing, to which modifying agents were added (electrolytes or surfactants). Optimum conditions were established for carrying out the precipitation process of active silicas. The basic physicochemical properties of the precipitated silicas have been established as well as their porosity, surface morphology, crystalline character, absorbing capacity, etc. (C) 1997 Elsevier Science B.V.