Chemical Looping Conversion of Coal Using Modified Iron Ore Oxygen Carrier

Oxygen carriers modified by K, Na, Ca, Ni, Mn and Cu were synthesized by the mixed calcination method. The physical and chemical properties of the oxygen carriers were firstly characterized using the X-ray diffraction (XRD) and H2 temperature programmed reduction (H2-TPR), and then the reaction performance of the modified oxygen carriers with lignite was studied based on the thermogravimetric experiments. The H2-TPR experiments found that the reactivity of six modified oxygen carriers was significantly higher than that of unmodified oxygen carrier due to the formation of new phases in solid solution. The reactivity of K-modified iron ore is better than that of Na- and Ca- modified iron ore and the reactivity of Cu- and Ni-modified iron ore is better than that of Mn- modified iron ore. The thermogravimetric experiments found that the best reaction performance between the iron ore and the lignite is achieved at the mixed ratio of 5:5-6:4. The K-modified iron ore has a higher reactivity than the Ni-modified iron ore for lignite conversion. © 2020, Editorial Office of Acta Petrolei Sinica(Petroleum Processing Section). All right reserved.