International Journal of Hydrogen Energy, Vol.41, No.48, 22846-22855, 2016
Synthesis and characteristics of BaSrCoFe-based perovskite as a functional material for chemical looping gasification of coal
Perovskite-type oxides have attracted considerable attention as advanced materials with redox stability. In this study, four different types of perovskite oxides were used in chemical looping gasification (CLG) to enhance carbon conversion and gas production. The performances of perovskites for CLG were investigated in a fixed-bed reactor. The perovskite oxides were characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF), and scanning electron microscopy (SEM). Results demonstrated that all of the perovskites could improve both the yield and the quality of gas production. Particularly, Ba0.5Sr0.5Co0.8Fe0.2O3-delta perovskite (BSCF) exhibited the best performance. Moreover, the gas production in the CLG process was improved by increasing the reaction temperature and using steam/hydrogen mixed atmosphere. The optimal gasification temperature and steam/hydrogen ratio for BSCF were approximately 850 degrees C and 0.641, respectively. The performance of BSCF stabilized after six cyclic experiments. Moreover, XRD, XRF, and SEM results showed that BSCF is capable of structural recovery and exhibits stable elemental composition in mixed atmosphere. BSCF has good cyclic performance and is a promising oxygen-carrier material for gasification. (C) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.