Silica_sulfuric_acid
Silica sulfuric acid (SiO
2-OSO
3H
2, SSA), a solid acid, is prepared by soaking silica gel with sulfuric acid.[1] SSA is used as a catalyst in different organic synthesis process.[2][3] Silica sulfuric acid is considered as cheap, nonhazardous and easy to handle solid acid catalyst with high acidity.[4]