Effect of preparation pH on pore structure of silica gels

Abstract

Surface characterization of silica gels prepared at different gelation pH from water glass and sulphuric acid were made by argon adsorption at 77 K using continuous volumetric method. While microporous silica gels prepared in the pH range of 1–3 had BET surface areas of 504–571 m² g⁻¹, total pore volumes of 0.26–0.31 cm³ g⁻¹ and micropore volumes of 0.16–0.23 cm³ g⁻¹, mesoporous silica gels prepared in the pH range of 3.36–0.65 had BET surface areas of 374–530 m² g⁻¹ and pore volumes of 0.61–0.79 cm³ g⁻¹.