MFI and FAU embryonic embryonic zeolites: synthesis and catalytic properties

Abstract

Zeolites are an important class of materials with many applications, among them the use in basic or acidic heterogeneous catalysis, depending on the control of the physical and chemical properties during or after their synthesissyntheses. Several modifications have already been extensively made in the zeolites, such as syntheses of crystals of nanometric dimensions and zeolitic slides obtained with the use of organosilanes, all with the aim of reducing the diffusion restrictions and increasing the catalytic performance. Currently, the embryonic zeolites, which are partially formed and with their extremely accessible active sites, appear as a new material to be explored with innumerable and not evaluated synthesis syntheses conditions, including the characteristics kinetic study of theirof the material under formation. Therefore, the present work aims to amplify the synthesis parameters in order to obtain the embryonic zeolites of the MFI and FAU structure with different Si/Al ratios and to evaluate the accessibility, activity of their acidic sites and its structural stability. The embryonic zeolites will be synthesized evaluating the time, temperature and aging of synthesis, and then characterized to establish the relation property-function synthesis with the objective of finding embryonic structures with specific application for a certain catalytic function. Finally, the catalytic activity of the embryonic and also of the crystalline zeolites will be evaluated through the reaction of dihydroxyacetone isomerization to lactic acid. Thus, the structural and morphological characteristics, besides the chemical composition of each zeolite, can be evaluated and correlated to catalytic activity, accessibility to acid sites and stability.