High performance of la‐promoted Fe 2 O 3 /α‐Al 2 O 3 oxygen carrier for chemical looping combustion

Iron oxide supported oxygen carrier (OC) is regarded to a promising candidate for chemical looping combustion (CLC). However, phase separation between Fe 2 O 3 and supports often occurs resulted from the severe sintering of supports during calcination, which leads to the sintering and breakage of Fe 2 O 3 thus the decrease of redox reactivity. In this article, La‐promoted Fe 2 O 3 /α‐Al 2 O 3 were used as OCs for CLC of CH 4 and for the first time found that the OC with the addition of 18 wt % La exhibited outstanding reactivity and redox stability during 50 cycles of CLC of CH 4 . Such a superior performance originated from the formation of LaAl 12 O 19 hexaaluminate (La‐HA) phase with not only small particle size but also excellent thermal stability at CLC conditions, which worked as a binder to prevent the phase separation thereby the sintering and breakage of active species α‐Fe 2 O 3 were avoided during reaction. © 2017 American Institute of Chemical Engineers AIChE J , 63: 2827–2838, 2017