Facile Structure Tuning of a Methanol-Synthesis Catalyst towards the Direct Synthesis of Dimethyl Ether from Syngas

Abstract

Heterogeneous catalysts of bifunctionality offer improved process efficiency and enhanced product yield in multistep chemical transformations conducted in a consecutive manner. However, this has seldom been realized in coprecipitated catalysts owing to the complexity of the synthesis. By adjusting the synthesis protocol of an industrial methanol-synthesis catalyst as a model system, herein we demonstrate the bifunctional effect of Al2O3/Cu/ZnO catalysts to enable the direct production of dimethyl ether from synthesis gas with yields that are 2-3-fold higher than those obtained with their conventional counterparts, with a greater number of accessible Cu surface atoms and more Al2O3 acid sites existing at the external particle surface. This is achieved by preparing the fully developed Cu,Zn precursor of a specific structure with surface-decorated Al species. Our approach paves the way towards the rational design of multicomponent precipitated catalysts with tunable bifunctionality for practical cascade reactions.