Investigation of Chemical Looping Combustion of Coal with Fe2O3 Oxygen Carrier

The reaction of a Chinese coal PDS with Fe₂O₃ was investigated using thermogravimetric (TGA)-difference thermal analysis (DTA), with focuses on the effect from such four factors as atmosphere, oxygen excess number Φ, the reduced valence of Fe₂O₃ and the inert support Al₂O₃. It was found that CO₂ atmosphere facilitated the reaction of Fe₂O₃ with PDS, especially at the final stage, the exothermic reaction specialty of Fe₂O₃ with CO from PDS gasification decreased the heat needed, but both excess supply of Fe₂O₃ or PDS coal was not economical or detrimental for the full conversion of PDS, though the reaction characteristic temperatures at the two reaction stages shifted to lower temperatures; finally, the inclusion of inert support Al₂O₃ in Fe₂O₃ OC was beneficial to the reaction of PDS with Fe₂O₃ at the second stage but not advantageous to that reaction at the third reaction stages due to the hindrance from Al₂O₃ for the gaseous products of PDS to access Fe₂O₃.