Development and Performance of Iron Based Oxygen Carriers for Chemical Looping

Abstract

Chemical looping (CL) can serve for CO2 utilization. In analogy to the CL equivalent to steam reforming for hydrogen production, one can conceptualize a “CL dry reforming” (CLDR) scheme in which CO2 is used instead of steam as oxidant for reoxidation of the oxygen carrier material (OCM). A key issue in CL processes is the selection of an appropriate OCM. While a number of metals give reasonable CO2 reduction capacity, only iron offers high oxygen storage capacity from CO2 over a wide range of operating temperatures. First‐principles modeling provide insight into the optimal reaction conditions and the effect of composition on their oxidation/reduction. First‐principles modeling of the stability and reducibility of metal oxides has proven challenging. Approximate functionals used frequently in density functional theory (DFT) display important deficiencies when treating strongly correlated systems like transition metal oxides.