ИСТИНА

The potential of the in situ MAS NMR techniques for the unravel of the mechanism of hydrothermal synthesis of zeolite catalysts has been demonstrated on the examples of synthesis of Al-, Zr- and Sn-BEA materials. The techniques is shown to give insight into the mechanism of the main steps of synthesis, including, gel formation, gel aging, crystal nucleation, growth and recrystallation; to provide information on the kinetics of each reaction step; to enable detection intermediate species stable only under hydrothermal conditions. The comparison of the results of in situ MAS NMR experiments with ex situ studies performed using XRD, SEM, TEM, IR and adsorption techniques outlined that the kinetic parameters obtained using both approaches are in good agreement. Combination of these two approaches will lead to fast progress in understanding the mechanisms of synthesis of different solids and therefore will facilitate the development of novel advanced materials.