3D net-linked mesoporous silica monolith: New environmental adsorbent and catalyst

This paper reported the synthesis, characterization, adsorption and catalysis of new morphology-assisted functional SBA-15, the 3D net-linked mesoporous silica monolith, and its actual function in selective reducing tobacco specific nitrosamines (TSNA) level of smoke, in order to explore the new route elevating the efficiency of environment adsorbents/catalysts through their morphology controlling. It is feasible to control the hydrolization and condensation of silica source in synthesis, and then piloting the formation and the secondary arrangement of primary particles, finally forming the monolith with 3D net-linked morphology. The resulting sample not only had the shape of monolith, but also possessed a considerable mechanical intensity hence it could be directly sieved for use without molding. With the assistant of net-linked morphology, this monolith sample could intercept the particles with μm sizes in tobacco smoke, and selectively capture the TSNA adhered on the particle, providing new functional material for environment protection. Through dry-impregnation it is also successful to modify the monolith with zirconia guest without damage of 3D net-linked morphology, dramatically increasing the activity of the composite in the instantaneous adsorption of volatile nitrosamine such as N-nitrosopyrrolidine (NPYR) and the temperature programmed surface reaction (TPSR) of N′-nitrosonornicotine (NNN), offering a powerful environmental catalyst to degrade carcinogenic pollutants.