The hexafluosilicic acid

a by-product in phosphate fertilizer industry

was used as the raw material for hydrothermal synthesis of mesoporous titanosilicates with cetyltrimethylammonium bromide (CTAB) as the cationic surfactant and ammonia as neutralization agent. The influence of synthesis conditions including hydrothermal time

the ratio of CTAB to silica

Si/Ti ratio

and surfactant removal methods on the structures and properties of mesoporous titanosilicates were investigated by characterization of the resulting product with techniques of X-ray diffraction (XRD)

nitrogen adsorption/desorption

scanning electron microscopy (SEM)

solid UV light scattering. At the optimized synthesis condition of the ratio of SiO2:CTAB:Ti(OC4H9)4:NH3:H2O=1:1.50:0.03:10:150 and the hydrothermal time of 5 h

mesoporous titanosilicate had specific surface area of 1116 m2·g-1 and porosity of 0.79 cm3·g-1. When used as catalyst for cyclohexene epoxidation. this mesoporous titanosilicate showed good catalytic activities with cyclohexene conversion of 68.10%

cyclohexene epoxide selectivity of 96.60%

and turnover frequencies of Ti active sites of 99.5 h-1. This new synthesis technique will greatly improve profit of phosphate fertilizer industry by utilizing the by-product hexafluosilicic acid for the production of value-added mesoporous titanosilicate.