High performance of la-promoted Fe2O3/-Al2O3 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 Fe2O3 and supports often occurs resulted from the severe sintering of supports during calcination, which leads to the sintering and breakage of Fe2O3 thus the decrease of redox reactivity. In this article, La-promoted Fe2O3/-Al2O3 were used as OCs for CLC of CH4 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 CH4. Such a superior performance originated from the formation of LaAl12O19 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 -Fe2O3 were avoided during reaction. (c) 2017 American Institute of Chemical Engineers AIChE J, 63: 2827-2838, 201