The Influence of Hydrogen-Permeable Membranes and Pressure on Methane Dehydroaromatization in Packed-Bed Catalytic Reactors

Computational simulations are developed and applied to study the coupling of packed-bed methane dehydroaromatization (MDA) reactors with hydrogen-selective membranes, for the production of value-added fuels, particularly benzene. Detailed chemical kinetics for reforming over bifunctional Mo/H-ZSM-5 catalysts are validated against published literature, and simulations explore the effect of hydrogen removal and operating conditions. Although results reveal that membrane integration significantly increases conversion, the desired benzene selectivity decreases, due to the increased yield of undesired byproducts such as naphthalene. The benzene-to-naphthalene ratio depends strongly on hydrogen removal, and simulations demonstrate that hydrogen membranes are most beneficial at relatively high GHSV and relatively low catalyst temperature. Increasing pressure decreases conversion and benzene selectivity, but increases benzene production rates and does not affect naphthalene selectivity. Single-pass benzene yield remains low; however, results predict that multipass reactor designs with hydrogen membranes and increased pressure can operate continuously to increase benzene production rates. (Figure Presented).