Reaction Kinetics of Mixed CuO–Fe2O3 with Methane as Oxygen Carriers for Chemical Looping Combustion

Reduction kinetics of alumina supported mixed Cu–ferrite oxide by methane was investigated for chemical looping combustion by the thermogravimetric analyzer (TGA) in the temperature range of 750–900 °C using continuous streams of 10%, 20%, and 30% CH4 concentrations balanced by helium. The rate of reduction was determined by weight change. The variations of activation energies and n values (JMA exponent) during the reduction conversion indicate that the methane combustion with CuO and Fe2O3 proceeds via a multistage reaction process. A kinetic model based on three parallel reactions was applied to the reduction data. The analysis of reduction showed that three reduction steps proceed simultaneously with the activation energies of 55.32 ± 3.11, 70.0 ± 2.0, and 165.0 ± 5.4 kJ/mol, respectively.