Synthesis and characterization of amino modified zinc and nickel ZIF-8 structures for CO2 methanation and analysis by in operando Raman spectroscopy conditions

• Grant number: 24/18617-9
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: January 01, 2025
• End date: December 31, 2025
• Field of knowledge: Engineering - Chemical Engineering - Chemical Technology
• Principal Investigator: Luiz Gustavo Possato
• Grantee: João Pedro Dias Querino
• Host Institution: Faculdade de Ciências (FC). Universidade Estadual Paulista (UNESP). Campus de Bauru. Bauru , SP, Brazil
• Associated research grant: 21/05246-4 - In situ and operando studies of heterogeneous catalysts for CO2 conversion, AP.JP

Abstract

Zifs (imidazolate framework) are a subclass derived from MOFs (Metal-Organic Frameworks) that are currently gaining relevant attention due to their high crystallinity and porosity, fascinating chemical stability and very high thermal stability (±400°C). ZIFs have a tetrahedral molecular structure, formed by divalent metal cations (Zn2+, Co2+ and Ni2+) linked to the organic ligand 2-methylimidazole. With these characteristics, ZIFs are great candidates to be used as research into the occurrence of CO2 methanation, which consists of reacting carbon dioxide with hydrogen gas and forming methane gas (CH4) and water, due to its high thermal stability This occurrence of methanation presents high yields of CH4 at high temperatures, between 300°C and 400°C. However, studies have shown that crystal sizes influence the structural stability of ZIF. Where larger crystals cause the compound to present greater thermal and structural stability, due to its crystalline structure being more cohesive, and smaller crystals cause it to present lower thermal and structural stability, due to the presentation of structural defects in ZIF. The main objectives of this project are to synthesize and characterize the ZIF-8 structures, as it has high stability (above 400°C) and to monitor its structure during catalytic activity, using the in operando Raman spectroscopy technique conditions. or in situ, to determine the relationship between crystal size and CH4 yield during the occurrence of CO2 methanation at high temperatures.