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

Abstract

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 (La_0.6Sr_0.4FeO_3-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.