Sulfuric Acid-Activated Silica Gel as a Potential Solid Acid Catalyst

Abstract

The conversion of silica gels into sulfated silicas (SO4/SiO2) have been carried out. The sulfation process of the catalysts was carried out by impregnation of sulfuric acids at concentrations of 1; 2; and 3 M and calcination temperatures of 500, 600, and 700 °C. Sulfation with 2 M H2SO4 and calcination temperature of 600 °C (SS2-600) produced a catalyst with the highest acidity value (5.13 mmol NH3 g-1). XRD analysis showed the formation of amorphous SiO2 phase, whereas SSA analysis showed that the SS2-600 catalyst had a mesoporous structure with a surface area of 147.728 m2/g, a total pore volume of 0.25 mL/g and a pore diameter of 6.439 nm. Characterization results show that sulfated silica gels have potency as solid acid catalysts.