Experimental investigation of La0.6Sr0.4FeO3-δ pellets as oxygen carriers in a counter-current packed-bed reactor for efficient chemical looping CO2 splitting

The application of chemical looping for reverse water gas-shift provides an efficient way for the conversion of CO2 to CO, enabling the transformation of captured CO2 into value-added products. For example, by using the produced CO along with renewable H2 to synthesise liquid fuels. In this study, we applied the concept of a chemical ‘memory’ reactor, employing a perovskite-based oxygen carrier (La0.6Sr0.4FeO3-δ, LSF) in a counter-current packed-bed reactor for CO2 splitting. This approach overcomes the chemical equilibrium limitation and could produce high purity CO. Our work experimentally investigated the performance of LSF pellets as oxygen carriers in a large lab-scale packed-bed reactor with gas switching technology for chemical looping CO2 splitting. We evaluated the effects of changes in feed time, bed temperatures, and flow rates on CO2 to CO conversion. Optimal conditions gave over 90 % CO2 to CO conversion via counter-current flow, compared to 45 % for conventional co-current flow in the same reactor. Higher bed temperatures enhanced the CO2 to CO conversion. [Display omitted] •La0.6Sr0.4FeO3-δ pellets were investigated in a reverse-flow chemical looping reactor for CO2 splitting.•Nearly complete CO2 to CO conversion can be achieved without thermodynamic limitations.•Effects of changing in bed temperature, feed time, and flow rates on CO2 conversion have been evaluated.•La0.6Sr0.4FeO3-δ pellets exhibits stable performance over CO2 splitting tests.