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论文类型：期刊论文

发表时间：2017-12-31

发表刊物：CHEMICAL ENGINEERING SCIENCE

收录刊物：SCIE、EI

卷号：174

页面范围：259-267

ISSN号：0009-2509

关键字：Chemical looping reforming; Perovskite; Intelligent oxygen carrier; Promoter

摘要：Chemical looping reforming (CLR) of ethanol is a novel method to produce hydrogen. It's vital to select an appropriate oxygen carrier (OC) with favorable catalytic activity and high stability for successive redox processes. In current research, the intelligent perovskites La2-xMxNiO4-lambda (M = Ca, Sr and Ce) were used as OCs and prepared by co-precipitation method. The 'intelligence' was embodied in exceptional self-recovery ability of perovskite during oxidation stage of CLR process, which was confirmed by the movement that Ni ions escaped and regained back to original position during oxidation step. The experimental result indicated that the movement effectively restrained the growth of metallic Ni and resulted in high activity of OC during life-time service and aging. Furthermore, the influence of promoters doping on the regeneration characteristics of OCs was investigated by BET, TEM, XRD, ICP-OES, TG and a fixed-bed experiment. From the perspective of catalytic performance, the addition of promoter strongly improved the reducibility of OCs, and the optimal substitution is Ca. The LNO-Ca OC exhibited favorable reducibility of nickel ions, shorter 'dead time', higher yield of hydrogen, superior ethanol conversion, stronger anti-carbon ability and excellent reproducibility of perovskite during successive redox reactions. (C) 2017 Elsevier Ltd. All rights reserved.