A particle-scale reduction model of copper iron manganese oxide with CO for chemical looping combustion

Chemical looping combustion is a promising power generation technology that produces sequestration-ready CO2 and heat/power from the combustion of fossil fuels with oxygen provided by an oxygen carrier, or metal oxide, rather than air. Successful implementation of chemical looping combustion depends highly on the choice of oxygen carrier and the development of reaction rate parameters for process design and scale-up of the multi-reactor system. In this work, the reaction profile of a promising trimetallic oxygen carrier, copper iron manganese oxide with CO, a component of coal-derived synthesis gas was characterized using differential scanning calorimetry/thermogravimetric analysis and in-situ X-Ray diffraction. A unique phase formation with reactivities different from that with single metal components and phase changes during the reaction with CO were identified. Three major reactions were identified from the phase changes to use for reaction modelling. A particle-scale reaction model was selected which best described the experimental thermogravimetric analysis data to determine the valuable intrinsic reaction values for reactor design and scale-up. A particle-scale reaction model based on nucleation and growth and 1-D phase boundary behavior exhibited the most accurate correlation with the experimental data and provided intrinsic rate constants which were validated with the conventional mass transport analysis.