This project has the objective to study the creation of mesoporous in zeolites for the desilication process and the catalytic effect in chemical reactions that use molecules of reagents and products with bigger kinetic diameter than the micropores. This is a branch of great interest considering mesoporous materials are of fundamental importance in the heterogeneous catalysis due to greater diffusivity of these composites in relation to the microporous materials, causing to the bigger conversion of the reagents. Desilication of zeolítica ZSM-5 (with structure MFI) it will be carried through varying the OH-/Si ratio for posterior analysis of the optimal conditions in accordance with the result of the volume of mesoporous and its relation with the catalytic activity. The kinetic of the desilication will be evaluated on the basis of the variation of pH. The zeolites will be analyzed by difratometria of X rays (XRD), scanning electron microscopy (SEM), atomic absorption spectrometry (AAS), physical adsorption, mercury porosimetry, the nuclear magnetic resonance of Si and Al and chemical adsorption of ammonia (TPD-NH3). The catalytic evaluation of zeolites contends mesopores will be done through the reaction of cetalização of glycerol, a byproduct of the transesterification reaction for the production of biodiesel, with acetone. The metalization has as the main product the socket, a compound of high aggregate value being applied as an additive in the biofuels, in order to aid the cold flow. This reaction will provide representative results since the products are more voluminous than the reagents, which will make it possible to study the formation and effectiveness of the mesopores obtained in the zeolitic structure by the deserialization technique. Moreover, the selectivity variation with the increase of mesoporosity in this structure may also be observed.
News published in Agência FAPESP Newsletter about the scholarship: