Achieving enhanced and robust propane selective oxidative dehydrogenation via electrically-driven continuous chemical looping

Oxidative propane dehydrogenation (OPDH) has emerged as a promising approach for direct propylene production. However, it still confronts great challenge of overoxidation of propane to COx, damaging the products selectivity. Herein, we report an electrically-driven continuous chemical looping process to efficiently produce propylene via an electrochemical CO2-OPDH system within solid oxide electrolysis cells (SOECs). At an optimal current density of 10 mA cm−2, the system with a Co3O4-modified La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) anode achieves 92.6% olefin selectivity and 14.2% single-pass propane conversion. This current-driven configuration boosts the propylene yield (5.11 mmol gtotal−1 h−1) by a factor of 18.5 over the open-circuit baseline. The electrochemical CO2-ODHP system also exhibits good stability during a 120-hour durability test. In-situ characterization and theoretical calculations elucidate the electrically driven online replenishment mechanism of Co3O4 lattice oxygen by O2- derived from cathode CO2 reduction. This dynamic cycle maintains moderate anode surface oxygen activity, resulting in highly efficient and selective OPDH without significant over-oxidation or cracking of propane. Oxidative propane dehydrogenation (OPDH) for propylene production is promising but limited by overoxidation. Here, the authors report an electrically driven chemical looping process using solid oxide electrolysis cells, which achieves high propylene selectivity in CO2 OPDH via anode catalyst design.