Intensification of the Reverse Water Gas Shift Reaction by Water-Permeable Packed-Bed Membrane Reactors

Abstract

The intensification of the reverse water gas shift (RWGS) reaction by water-permeable packed-bed membrane reactors (PBMRs) is studied to produce syngas using a CuO/ZnO/Al₂O₃ catalyst at 250 °C and 5 bar. Using experimental data from the literature, a modified kinetic model is developed for the RWGS reaction rate of the catalyst at low temperatures. The effects of gas hourly space velocity, H₂ to CO₂ ratio, H₂O/H₂ perm-selectivity, and sweep to reactor pressure and flow rate ratios are studied on the performance of the RWGS PBMRs for co- and counter-current flow configurations. The RWGS PBMRs are proven to be effective in overcoming equilibrium limitations of the RWGS reaction under different operating conditions. An optimization is performed to minimize the volume of the RWGS PBMRs to produce syngas for methanol synthesis. The optimization results show that the membranes are effective to produce the desired syngas under different operating conditions and flow configurations.