ABSTRACT
The chemical-looping combustion of propane with the use of hematite and alumina-supported hematite carriers was studied in a fixed-bed reactor at 960°C, 910°C, and 870°C. In multiple cycles of the reduction/oxidation process, the concentrations of CO2 and CO in outlet gases were measured. The reactivity of the carriers was lowest in the first cycle. The conversion of propane was getting worse when the flow rate of propane was too high. The samples of the hematite carrier in the reduction stage were examined by X-ray diffraction (XRD) and thermogravimetric analysis (TGA) methods. Wustite and magnetite were detected as reduced forms of hematite. The theoretical analysis of the reduction paths of hematite by the propane decomposition products to Fe3O4, FeO, and Fe were conducted to investigate the pattern of the CO2 curve.
Acknowledgments
The authors thank Mr. Jacek Pasierb and Piotr Mondkiewicz, Department of Heat Engineering and Environment Protection, for the technical assistance.