CARATTERIZZAZIONE MULTI-TECNICADI CATALIZZATORI BIFUNZIONALI PERLA CONVERSIONE IN CASCATA DI CO2 ADOLEFINE

The present Master thesis work is part of the EU project COZMOS, where an ultimate approach to directly convert CO2 to light olefins through methanol-mediated cascade reactions over bifunctional catalysts is explored. The process connects the hydrogenation of CO2 to methanol via a metal or metal oxide phase and its subsequent conversion to olefins over an acid zeolite/zeotype in the single reactor. Here, the coexistence of two catalysts is challenging and needs detailed investigation of the process bottlenecks. Indeed, each catalyst should be fully optimized for its primary reaction. Simultaneously, the two active phases should not be contaminated by one another; for example, H2O produced as a by-product in the second stage of the process may cause sintering of the CO2 conversion to Methanol catalyst. Additionally, at elevated operational temperatures, the interdiffusion between the two phases should be considered since it could lead to physicochemical properties alteration of two materials. As a result, extensive determination of surficial, textural, and structural characterization of both individually and the bifunctional catalyst system is crucial. In this work, the catalyst system of ZnxCeyZr1-yO4 and acid zeotype H-RUB-13 were chosen as this system is shown promising primary results as active bifunctional catalysts towards the targeted cascade process for CO2 valorisation.