Confined nucleation and growth of MFI type zeolites containing Fe3O4 nanoparticles using reverse microemulsion (water-in-oil) system for the preparation of magnetic core-zeolitic shell nanostructures

• Grant number: 20/02289-1
• Support type: Scholarships abroad - Research Internship - Post-doctor
• Effective date (Start): October 27, 2020
• Effective date (End): October 26, 2021
• Field of knowledge: Engineering - Chemical Engineering
• Principal researcher: Ernesto Antonio Urquieta Gonzalez
• Grantee: Diógenes Honorato Piva
• Supervisor abroad: Svetlana Mintova
• Home Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil
• Research place: Laboratoire Catalyse & Spectrochimie (LCS), France
• Associated to the scholarship: 18/25649-3 - Nucleation and growth of zeolite MFI-Type structure on the surface of Fe3O4 nanoparticles for the preparation of magnetically separable nanocatalysts, BP.PD

Abstract

This postdoctoral project aims to develop Fe3O4@MFI (MFI = Silicalite-1 and ZSM-5) core-shell nanostructures (< 100 nm) with discrete, uniform, and finely tunable shell thickness without the generation of core-free zeolite particles. For this purpose, reverse microemulsion mediated hydrothermal method will be adopted and a comprehensive study of the nucleation and growth process of zeolite crystal inside this system will be accomplished. Our previous results have indicated that this approach provided a confined space for both silicalite-1 crystal growth and core-shell nanostructure formation. However, the results also showed that reverse microemulsion for the core-shell formation occurs mainly during the aging period and the subsequent hydrothermal treatment at higher temperature, necessary for the crystallization of zeolites, appears to destroy it. Therefore, in order to understand this phenomenon and provide a strategy for synthesizing zeolitic core-shell materials, we aim to evaluate the role of synthesis parameters such as aging time, hydrothermal temperature, concentration of zeolite synthesis mixture, concentration of surfactant and co-surfactant, as well as the Fe3O4 nanoparticles content. The dependence of nucleation and growth process of zeolite crystals with the above parameters will be evaluated by using techniques such as high-resolution transmission electron microscopy (HRTEM), Dynamic Light Scattering (DLS) and X-ray diffraction (XRD). It is expected that the results achieved should contribute to the current research on magnetic zeolite with core-shell structure thathas been carried out at Center of Excellence for Research in Sustainable Chemistry (CERSusChem). (AU)