Effect of Ordered Mesoporous Alumina on Mass Transfer to Enhance Dimethyl Ether Carbonylation of Shaped Mordenite Catalysts

Driven by the increasing global energy demand, developing efficient catalytic processes for sustainable ethanol production from dimethyl ether (DME) carbonylation has gained significant attention. To optimize the performance of shaped catalysts for DME carbonylation, we systematically investigated the role of ordered mesoporous alumina as a binder component. Structural characterization revealed that increasing the proportion of mesoporous alumina in the binder systematically reduced the microporosity while simultaneously enhancing the mesoporous surface area. Acidic property analyses demonstrated that despite the decrease in microporosity, the total acid density remained relatively constant. Notably, catalytic performance evaluations illustrated that the catalyst with 20% mesoporous alumina exhibited significantly enhanced catalytic activity due to improved pore connectivity and mass transfer properties. DME diffusion studies, analyzed through standard and time-fractional diffusion models, further confirmed that mesoporous alumina incorporation significantly improved molecular diffusion, resulting in decreased activation energies for diffusion. These findings provide valuable insights for the future rational design of shaped catalysts, demonstrating that carefully adjusting the proportion of ordered mesoporous alumina effectively balances the catalyst porosity and mass transfer properties to maximize catalytic performance.