(560ec) Influences of Metal-Modification and Lamellar Zeolite Structure on Ethylene to Liquid Aromatics Conversion Reaction Using MFI Catalysts

Efficient conversion of short chain olefins such as ethylene to liquid aromatics using zeolites as catalysts is industrially important. The challenges of this reaction include the formation of undesired polyaromatic compounds and solid carbonaceous species (coke) resulting in deactivation of the catalyst. Addition of mesopores in zeolite structures provides higher mass-transfer for reactants and products and might increase the selectivity of the reaction for desired aromatics. Metal modification of the zeolites has been shown to decrease the coke formation rate in these catalysts. Therefore, the effects of meso-/microporous structure and metal modification with gallium or zinc on catalytic performances of lamellar MFI zeolites in ethylene conversion reaction to liquid aromatics were investigated. The characterization results showed that the zeolite structure is a pivotal factor for controlling the type, size, and distribution of metal dopant species forming on zeolite. Adding metal dopants to lamellar zeolite structures changed the acidity properties of the catalysts and increased the liquid aromatics yield and selectivity for mono-benzene alkylated aromatics while decreased the coke formation rate compared to their microporous commercial MFI analogies. The metal modified lamellar MFI zeolites as bifunctional catalysts open an avenue for converting biomass derived molecules to desired products.