Ca_(2)MnO_(4)-layered perovskite modified by NaNO_(3)for chemical-looping oxidative dehydrogenation of ethane to ethylene  

作　　者：Weixiao Ding Kun Zhao Shican Jiang Zhen Huang Fang He 

机构地区：[1]College of Chemistry and Bioengineering,Guilin University of Technology,Guilin 541006,China [2]Guangzhou Institute of Energy Conversion,Chinese Academy of Sciences,Guangzhou 510640,China [3]School of Chemistry and Chemical Engineering,Nanjing University of Science and Technology,Nanjing 210094,China

出　　处：《Chinese Journal of Chemical Engineering》2024年第4期53-64,共12页中国化学工程学报（英文版）

基　　金：support of National Natural Science Foundation of China(22179027);gratefully acknowledged.This work was also supported by the Natural Science Foundation of Guangxi Province(2021GXNSFAA075063,2018GXNSFDA281005);the National Key Research and Development Program of China(2017YFE0105500);Science&Technology Research Project of Guangdong Province(2017A020216009).

摘　　要：Chemical-looping oxidative dehydrogenation(CL-ODH)is a process designed for the conversion of alkanes into olefins through cyclic redox reactions,eliminating the need for gaseous O_(2).In this work,we investigated the use of Ca_(2)MnO_(4)-layered perovskites modified with NaNO_(3) dopants,serving as redox catalysts(also known as oxygen carriers),for the CL-ODH of ethane within a temperature range of 700-780℃.Our findings revealed that the incorporation of NaNO_(3) as a modifier significantly-nhanced the selectivity for-thylene generation from Ca_(2)MnO_(4).At 750℃and a gas hourly space velocity of 1300 h^(-1),we achieved an-thane conversion up to 68.17%,accompanied by a corresponding-thylene yield of 57.39%.X-ray photoelectron spectroscopy analysis unveiled that the doping NaNO_(3) onto Ca_(2)MnO_(4) not only played a role in reducing the oxidation state of Mn ions but also increased the lattice oxygen content of the redox catalyst.Furthermore,formation of NaNO_(3) shell on the surface of Ca_(2)MnO_(4) led to a reduction in the concentration of manganese sites and modulated the oxygen-releasing behavior in a step-wise manner.This modulation contributed significantly to the enhanced selectivity for ethylene of the NaNO_(3)-doped Ca_(2)MnO_(4) catalyst.These findings provide compelling evidence for the potential of Ca_(2)MnO_(4)-layered perovskites as promising redox catalysts in the context of CL-ODH reactions.

关 键 词：Chemical-looping oxidative DEHYDROGENATION ETHANE ETHYLENE NaNO_(3)-doped Ca_(2)MnO_(4)redox catalyst Layered perovskites 

分 类 号：TQ221.211[化学工程—有机化工] TQ426