Abstract

A procedure for the preparation of amorphous silica spherical macroparticles using strongly basic anion exchange gel resins as shape directing macro-templates is presented. Resin beads were hydrothermally treated with either clear homogeneous TPA–silicate solutions containing tetraethoxysilane, tetrapropylammonium hydroxide and distilled water or with sodium silicate solutions. As a result of the ion exchange of silica species into the resin structure, resin–silicate composites were formed. After separation and drying of the resin–silicate composites, the resin was removed by combustion leaving solid spherical silica particles with surface areas exceeding 1000 m² g⁻¹. Two types of gel resins having different active groups and degrees of cross-linking were employed and the products obtained were characterised by SEM, Raman spectroscopy and nitrogen adsorption measurements. The type of the resin as well as the type of silicate solution used were of great importance for the pore structure of the final materials.