Reduction kinetics of SrFeO_(3−δ)/CaO∙MnO nanocomposite as effective oxygen carrier for chemical looping partial oxidation of methane  

作　　者：Xinhe Wang Liuqing Yang Xiaolin Ji Yunfei Gao Fanxing Li Junshe Zhang Jinjia Wei 

机构地区：[1]State Key Laboratory of Multiphase Flow in Power Engineering,Xi’an Jiaotong University,Xi’an 710049,China [2]School of Chemical Engineering and Technology,Xi’an Jiaotong University,Xi’an 710049,China [3]Institute of Clean Coal Technology,East China University of Science and Technology,Shanghai 200237,China [4]Department of Chemical and Biomolecular Engineering,North Carolina State University,Raleigh,NC 27695,USA

出　　处：《Frontiers of Chemical Science and Engineering》2022年第12期1726-1734,共9页化学科学与工程前沿（英文版）

基　　金：This work was financially supported by the National Natural Science Foundation of China(Grant No.21978230);Shaanxi Creative Talents Promotion Plan−Technological Innovation Team(Grant No.2019TD-039).

摘　　要：Chemical looping reforming of methane is a novel and effective approach to convert methane to syngas,in which oxygen transfer is achieved by a redox material.Although lots of efforts have been made to develop high-performance redox materials,a few studies have focused on the redox kinetics.In this work,the kinetics of SrFeO_(3−δ)–CaO∙MnO nanocomposite reduction by methane was investigated both on a thermo-gravimetric analyzer and in a packed-bed microreactor.During the methane reduction,combustion occurs before the partial oxidation and there exists a transition between them.The weight loss due to combustion increases,but the transition region becomes less inconspicuous as the reduction temperature increased.The weight loss associated with the partial oxidation is much larger than that with combustion.The rate of weight loss related to the partial oxidation is well fitted by the Avrami–Erofeyev equation with n=3(A3 model)with an activation energy of 59.8 kJ∙mol^(‒1).The rate law for the partial oxidation includes a solid conversion term whose expression is given by the A3 model and a methane pressure-dependent term represented by a power law.The partial oxidation is half order with respect to methane pressure.The proposed rate law could well predict the reduction kinetics;thus,it may be used to design and/or analyze a chemical looping reforming reactor.

关 键 词：chemical looping reforming SrFeO_(3−δ) CaO·MnO nanocomposite reduction kinetics Avrami–Erofeyev model pressure-dependent term 

分 类 号：O64[理学—物理化学]