CHARACTERISTICS OF METHANOL CONVERSION TO DIMETHYL ETHER OVER ZEOLITE CATALYSTS

Production of dimethyl ether (DME), introduced as an alternative fuel to address the widespread use of fossil fuels, takes place through direct and indirect synthesis. The direct synthesis of DME combines methanol (CH3OH) formation, integrating both redox and acidic sites. The indirect method includes a two-stage process, starting with CH3OH synthesis from syngas (CO + H2) over Cu/ZnO/Al₂O₃ catalysts, following dehydration over acidic catalysts to form DME. The purpose of the paper was to study the conversion of CH3OH to DME and hydrocarbons on Al₂O₃ and H-forms of ZSM-5 zeolite, also modified with phosphoric acid. It was suggested that the formation of C2H4 in a structure-sensitive reaction occurs with the participation of the Brønsted acid center and the Lewis basic center.