Porous texture modifications of a series of silica and silica-alumina hydrogels and xerogels: A thermoporometry study

摘要

The objective of the paper is to identify and evaluate the influence of the main preparation operating parameters which govern the porous texture formation of silica and silica-alumina usable as catalyst support or matrix. The chosen preparation process is a sol-gel transition leading to hydrogels which are spray dried. The texture modifications of hydrogels and xerogels are evaluated from water thermoporometry, analytical method well suited to measurements on wet or dry gels. It allows to point out the influence of operating parameters of the preparation process and demonstrate that texture modifications induced in hydrogels still exist in xerogels. From the knowledge of texture evolution it is possible to master the pore texture of the end material.