Influence of various synthesis parameters on the morphology and crystal size of zeolite Zn-MFI

The use of the zinc-phosphate complex in the hydrothermal synthesis has been proven to be a good way for obtaining zinc-zeolite materials, especially in the case of the zeolite Zn-MFI that can be prepared in a large range of Si/Zn ratios [1, 2]. Moreover, the pH values of the starting hydrogel play an important role on the nature of the crystalline phases obtained. For that reason the first step in the synthesis optimization is the definition of the pH range that is specific for each zeolite type. The crystal size and morphology can be varied by altering the chemical synthesis parameters (zinc, organic and water content as the main ones) as well as the source of silica. Moreover, the isopropanol decomposition is carried out with the purpose to valuate the acidity of the prepared Zn-MFI samples.