Post-synthesis alumination of mesoporous silica SBA-15 with high framework aluminum content using ammonium hexafluoroaluminate

Incorporation of high aluminum contents into the silica framework of SBA-15 was achieved by treating SBA-15 with an aqueous (NH4)3AlF6 solution at pH 9.3 at room temperature. The Al-SBA-15 material thus obtained exhibited a high framework aluminum content (up to a bulk Si/Al ratio near 5), good structural integrity, and well-developed Brønsted acidity.