Combined carbon capture and catalytic oxidative dehydrogenation of propane to propylene conversion through a plug-flow dual-phase membrane reactor

Abstract

Combined carbon capture and conversion (3C) technologies play a vital role in our battle against global warming and climate. Using electrochemical cells for 3C is an attractive option due to their intrinsically high efficiency and selectivity. Here we report an electrochemical membrane reactor for CO2/O2 capture from flue gas and instant conversion of propane to propylene over a catalyst bed. The membrane consists of a dual metal-carbonate phase, which allows CO2/O2 (in 2:1 mol ratio) co-transport through the membrane. The reactor is in tubular plug-flow geometry, which enables a continuous and gradual addition of CO2/O2 into a flowing propane stream along the axial length of the membrane, thus achieving an excellent balance between conversion and selectivity, while avoiding overoxidation and suppressing coking. The plug-flow membrane reactor exhibits a C3H6 yield of ∼30 %, C3H8 conversion of ∼35 % and C3H6 selectivity of 85 % at 600 °C for an impressive 173 h of continuous operation with minimal degradation.