Surface Modification of Silicagels. Evaluation of Thermally - Treated Commercial Silicagels

Abstract

The chromatographic properties and the structure and texture of thermally treated silicagels have been studied. Commercial silicagels (Partisil and Lichrosorb) were thermally modified at 300, 400, 500, 600, 700, 800 and 900°C. The evolution of specific surface, pore volume and distribution of mean pore diameter as a function of temperature was investigated. It is shown that the modification at 600°C is the most interesting one: reducing the hydroxyl concentration of a silicagel by a controlled thermal treatment, all the surface hydroxyl groups could be involved in a chemical modification.